December 2002 Forecast Outlook, Discussion & Report Page

Victoria

Information

January 2003 Forecast Outlook, Discussion & Report page

Current Victorian and Australian Conditions

Overview: The high in the Tasman Sea has weakened slightly but remains strong and ridges along the Queensland coast. A trough moving through the north of Victoria during the afternoon, triggering showers and scattered storms in northern Victoria and southern New South Wales. A broad trough of low pressure extends from the north of the continent to a large low (998hPa) occupying much of the southern Bight. A cold front is crossing the southwest of the continent, while the high in the Indian Ocean is ridging southeast into the Bight.   A moisture plume from the Indian Ocean south of Indonesia is feeding more midlevel moisture onto the continent.  An active upper 300hPa trough is approaching the southwest of Western Australia. Darwin waterspout: videoed 28th December by Paul Mossman(ASWA - NT)

Discussion: The high in the Tasman will weaken slowly and move east, with the broad trough over the continent becoming more organised and deepening as it moves across South Australia and into Victoria during Monday and Tuesday, with the surface front catching up with the trough and the infeed of tropical moisture to continue.  An upper ridge will move through eastern Australia, temporarily stabilising conditions ahead of the trough. As the trough moves east through the eastern part of the continent, showers (with some heavy falls) and isolated storms are likely along its length. TC Zoe (920hPa) will continue to weaken and move southeast.  The upper cold pool in the Tasman Sea will move east and not affect Australia.

Rainfall potential
Victoria: Northeast to northerly winds and increasing temperatures moisture advected into the state may lead to widespread showers (with some good falls likely) and isolated storms, mainly in the west and on the ranges, slowly spreading into central districts. Isolated storms are less likely in the northeast and on the eastern ranges
NSW: Northeast to northerly winds will remain widespread ahead of the trough. Scattered showers and storms, predominantly in southern and western areas, occasionally extending to the north along the ranges.
Queensland:  Seasonal storm activity continuing in the north, particularly over Cape York and near the northern ranges. Showers and isolated storms developing in the west. Coastal showers in the south, becoming less frequent.
NT: Scattered showers and isolated storms mainly in the northwestern Top End and in the southwest, becoming more widespread.
WA:  Scattered showers in the south of the state with a moist onshore flow, with shower activity increasing with the passage of a front. Seasonal storm activity in the Kimberley, Pilbara and northern Interior.
SA:  Scattered showers and storms, mainly high based except in the south, are likely in the west, extending east and becoming general. Some heavy falls are possible.
Tasmania:  Scattered showers,with the risk of a storm, becoming more general through the early part of the week.

Overview: A high in the eastern Bight which extends into the Tasman, cradles a broad trough extending south through New South Wales. The ridge that developed along the east coast has helped edge this trough slightly further inland except over its southern extremity which has extended to the far southeastern corner of the state. A broad full depth trough through Western Australia extends to the western Bight and a small surface low pressure has become enclosed to the south of the state. A broad area of mid-upper level moisture is feeding southwest from near to Indonesia towards the northwestern coastline. TC Zoe lurks to the northeast.

Discussion: The high will move east and amalgamate into one centre in the southern Tasman with the ridge being maintained along the east coast.  The surface  trough through New South Wales will remain quasi-stationary, but extend southward into Victoria during the weekend.   The upper trough will move through the northeast of the state and southeastern Queensland. The likelihood of storm activity over the southeast will increase after the trough currently over Western Australia moves east over the weekend and into the early week and absorbs the current trough. With the exception of the ridge along the eastern coast, the majority of the continent will remain under the influence of general surface troughiness, although a weakening upper ridge moving through South Australia during Friday and Saturday and Victoria during Sunday  *may* tend to stabilise conditions albeit briefly as it moves through.

Rainfall potential
Victoria: A risk of an afternoon shower or storm in the far east and northeast Saturday. Northeast to northerly winds and increasing temperatures during the weekend, with showers and storms becoming more widespread early in the new week with the approach of the trough.
NSW: Northeast to northerly winds will be widespread through the weekend.   Coastal showers mainly in the north. Scattered showers and storms are most likely along the ranges, predominantly in southern and central areas.
Queensland:  Scattered showers and storms in central areas, with seasonal storm activity continuing in the north, particularly over Cape York and near the ranges. Coastal showers further south.
NT: Scattered showers and isolated storms mainly in the northwestern Top End and in the southwest.
WA:  Scattered showers and isolated storms within the trough moving through the central and southern parts of the state. Seasonal storm activity in the Kimberley region, mainly Saturday.
SA: Conditions becoming warm to hot through the weekend. Isolated showers and storms, mainly high based, are likely in the west, extending east through the weekend and becoming general.
Tasmania:  Isolated showers, mainly in the north and east.  Remaining mild to warm after cool nights.

Overview: The high remains in the Bight with a ridge building along the New South Wales coast and a deepening trough along the west of the Great Divide. General troughiness over the north of the continent has triggered widespread storms, mainly in the east. A significant moisture buildup, with a large moisture plume approaching from the Indian Ocean towards Western Australia should be monitored during the next few days. Temperatures this Christmas Day ranged from near 0°C on Mt Wellington, through the low 20's in Victoria to the low 40's in Queensland and Western Australia.

Discussion: The high will continue to weaken on its eastern side in the Bight, while the ridge along the New South Wales coast will strengthen and edge the deepening trough westward during Boxing Day. A broad trough will remain through the north of the continent dipping south along the west coast, with the Indian Ocean moisture plume bringing a significant amount of moisture, particularly above 500hPa, onto the continent and into the trough lying through Western Australia.

Interaction between a deepening upper trough moving across eastern Australia and the surface trough should mean a continuation of showers and storms, mainly in northern New South Wales (but extending further south for a time during Boxing Day) and southern Queensland.  Widespread showers and isolated storms over much of Western Australia, particularly in the Kimberley and within the trough.

Rainfall potential
Victoria: Increasing moisture levels in a northeasterly flow.  The risk of isolated storms in the far north as the trough deepens southward.  Isolated drizzle patches in the south, mainly along the coast overnight, clearing to a mainly fine day.
NSW: Scattered showers and storms through the north and northeast of the state mainly east of the trough, with the risk of isolated storms in the central and southern inland.  There is a chance that some of these storms (in the north) may be severe, and localised heavy falls are possible.
Queensland:  Scattered showers and storms in the east and southeast through Boxing Day.  Seasonal storms continuing in the north.
NT: Seasonal showers and storms in the Top End with scattered showers and storms south of Tennant Creek, mainly in the west.
WA:  Seasonal showers and storms in the Kimberley.  Scattered showers and isolated storms in the trough in the south, moving east.  Showers may develop in the west later.
SA: Increasing cloud and rising temperatures ahead of the trough moving into the west of the state. Isolated showers and high based storms in the northwest are likely.
Tasmania:  Cool tonight and becoming milder on Boxing Day.  Showers clearing.

Overview: A strong high in the Bight is sending a ridge through the Bass Strait area. A broad and deepening trough over the west of the continent has been triggering showers and isolated storms from the Pilbara and south inland of the coast. A trough extends from the front moving through the Tasman Sea, through northeastern New South Wales and southern Queensland, through the Territory and links into the low over the Pilbara.  Seasonal storms activity, although patchy, continues over much of the north. Strong thunderstorms over northeast New South Wales and southeast Queensland have continued. A weak front is crossing the south of Tasmania with a cold pool to the south of the island.  The southeast of the continent remains under a moistening southwesterly flow which has triggered isolated (ahem) drizzle patches.

Discussion: Not a great deal of change in the synoptic pattern is likely over the next day or so. The high in the Bight will take up residence over the next few days, but will be eroded and weaken over its eastern extremity. The west coast trough will continue bringing moisture into the state from the Indian Ocean during the next day or two and will deepen and extend further south. Outflow moisture from this trough will continue feeding east across the north of the continent as well as into the arm over the trough over New South Wales and southeast Queensland. This trough will extend further south at times with the axis remaining along the west of the Great Divide. A ridge building along the east coast from the high in the Bight will slow the eastward progression of the trough.

Rainfall potential
Victoria:  Isolated drizzle patches along the coast, remaining cloudy for much of the day south of the ranges,.  Fine and warm in the north.
NSW: Showers and storms continuing over the north and northeast of the state, with cooler conditions with isolated showers or drizzle patches in the southeast mainly along the coast.
Queensland:  Isolated showers along the coast, mainly north of Fraser Island with seasonal storms activity over the Cape York area.  Showers and storms over the southeast, tending to rain areas at times.
NT: Scattered showers and storms over the Top End with showers and isolated storms also likely in the west of the Territory, mainly in the north.
WA:  Scattered showers and isolated storms confuting over much of the state, with more activity likely in the north and the west.
SA: Mostly fine with the exception of isolated drizzle along the southeast and the chance of high based storms in the northwest nearer the trough.
Tasmania:  Isolated showers in the west and south.  Cool conditions continuing.

Overview: A broad surface trough occupies the northwest of the continent with a further trough extending southeast through New South Wales. An upper cold pool is moving northeast through northern New South Wales. The baric ridge is located near to 40°S, dissected by a small surface low and front in the Bight and the West Australian trough extending southeast from the Pilbara. A weak ridge remains along the Queensland coast. A strong upper ridge continues to lie negative longitudinally (ie: northwest - southeast) over Victoria, with a highly meridional setup located over our longitudes in the upper atmosphere.

Discussion: The trough moving through Western Australia on Friday night will continue to move east and become absorbed into the trough lying through eastern Australia during the weekend, while a surface low with associated front in the Bight will also move east. The upper ridge over the southeast of the continent will be pushed northward, and the upper trough will move over southern and central Queensland before moving over the Coral Sea later in the weekend. A trough will reform down the west coast during Saturday and Sunday and showers and storms are expected to continue through inland Western Australia associated with troughing.

Rainfall potential
Victoria:  Only isolated showers and storms over the ranges, more predominantly in the east and closer to the trough. Hot ahead of a weak front expected to cross the state mid to later in the weekend with scattered showers mainly in the south to follow.
NSW: Isolated showers and storms, mainly inland and over the central and possibly southern tablelands. A weak change moving through the south later in the weekend, may also trigger shower and storm activity.
Queensland:  Isolated showers and storms over much of the interior, mainly in the south and central eastern areas.  Isolated storms over the northern tropics, with scattered showers along the coast.
NT: Isolated storms throughout, mainly in the west.
WA:  Isolated showers and storms over the Kimberley, Interior  and east Pilbara down through the Goldfields, and extending east. Later in the weekend, showers and isolated storms near the influence of the deepening west coast trough. Light showers in the southwest with the passage of a weak front.
SA: A milder southwesterly windshift during the weekend as the ridge declines and shifts east and a trough moves through the state. Very hot conditions ahead of this change with isolated showers and storms to the east of the trough with only isolated showers behind it, mainly in the south.  Isolated high based showers or storms in the far north.
Tasmania:  Isolated showers developing with the passage of a weak front later in the weekend, mainly in the west and south.

Overview: The ridge of high pressure that has maintained its position between the Indian Ocean to the west of Perth to Tasmania has changed during Thursday to lie a little further north, which in turn has edged the southern extremity of the complex trough lying through the continent a little further north in New South Wales. This trough can still be traced back across the continent to the low in the Kimberley / Pilbara region and has been triggering storms again during Thursday.

A weaker ridge of high pressure is extending along the southern coastline of Western Australia, and the heat trough continues to deepen along the west coast. An upper ridge has stabilised conditions across Victoria, while an upper low over the Gascoyne / Goldfields area of Western Australia is triggering showers and storms.

Discussion: During Friday, a weak high will bud off from the ridge  in the Bight and move east, while the trough through the east of the continent looks to deepen southward again into northeastern Victoria during the day. The trough down the west coast will continue to deepen and begin to march east  towards the Goldfields while a front passes to the south of the continent. To the north, the low over the northwest of the continent will continue to trigger showers and storms. The upper ridge will likely persist over Victoria over the early part of Friday but begin to shift out later and during the weekend, while the upper trough will drift over inland Queensland. A front will cross southern Tasmania.

Rainfall potential
Victoria:  Likely early haze in the south, clear in the north.  Isolated showers and storms likely to develop over the ranges, mainly in the northeast during the afternoon.  Hot away from the coast and the influence of the sea breeze.
NSW: Showers and storms continuing along the western slopes and ranges.   Hot and dry to the west of the trough.  Isolated showers over the northeast coast.
Queensland:  Showers and storms developing inland mainly in the south and west of the central ranges.  Isolated storms in the tropical north continuing.
NT: Scattered showers and storms over much of the Territory, mainly in the western half.
WA:  Scattered showers and storms in the Kimberley through the Gascoyne, Goldfields and into the upper southwest.
SA: Isolated showers and storms through the inland with continuing hot conditions.   Milder on the coast.
Tasmania:  Chance of showers, mainly in the west and associated with the passage of a front.

Overview: The ridge of high pressure continues to lie from west of Perth through the Bight to near Tasmania with a ridge to the north and along the Queensland coast. A broad trough covers much of the continent from the northwest through to the southeast, while another more complex trough extends through New South Wales. Widespread storms along the ranges and over the northwest plains of New South Wales during the afternoon have resulted in some heavy falls with the slack upper flow leading to slooow moving storms. Moisture is continuing to build over the east of the continent.

Discussion: Other than the high near Tasmania moving slowly east and the West Australian trough continuing to deepen southwards, not a great deal of change in the surface synoptic setup is likely during the next 24 hours.  Another high in the series will bud off in the Bight and drift southeast along the ridge. The trough through New South Wales and Victoria is likely to wander a little west, with storms likely again along the ranges, extending westward as the available moisture increases.

In the upper levels a trough over Victoria and South Australia is likely to strengthen through Thursday but wind speeds will remain slack, so storms will be slow moving once again. This upper trough will wander backwards and forwards about the southeast of the continent, which may make forecasting significant weather during the next few days rather interesting.

Rainfall potential
Victoria:  Conditions continuing warm to hot inland, but tempered south of the ranges.  Isolated showers and storms, mainly along the ranges and possibly over the northern plains, extending further west than Wednesday as moisture increases.
NSW: Showers and storms continuing, mainly along the ranges. Some locally heavy falls from slow moving storms. Hot inland. Isoalted showers along the north coast in a moist onshore flow.
Queensland:  Isolated showers along the central and northern coasts. Occasional storms near the Gulf of Carpentaria and around Cape York, extending southeast along the west of the ranges during Thursday.
NT: Scattered showers and storms, mainly over the northwest of the Territory but extening southward during Thursday.  Isolated showers and the chance of a storm in the southwest.
WA:  Scattered showers and storms from the Kimberley through the Interior to the Eucla, with a further area of storms likely in the Goldfields associated with the upper trough and deepening surface trough inland from the west coast.  Isolated light showers along the southeast coast.
SA: Scattered showers and storms continuing through much of the inland, but sliding slowly southeast along the trough. Remaining hot inland but milder along the coast.
Tasmania: Mainly fine.

Overview: A ridge of high pressure lies from the west of Perth, southeast through the Bight and south of Tasmania before extending a ridge to join up with that from the high in the Tasman along the east coast.  This setup has slowed the eastward movement of the broad trough currently located across the continent from the northwest to the east and southeast. Northwestern Australia remains under a broad area of low pressure with isolated seasonal storms.  Storms, mainly along the ranges in Victoria and New South Wales have been triggered in the trough during Tuesday, but moisture has again been somewhat lacking with upper winds remaining slack. Temperatures in Victoria, South Australia and southern New South Wales today have been extreme inland of the ranges in particular. Storms have also been triggered in the trough moving through Western Australia.

Discussion: Little change from today is expected during Wednesday over eastern Australia. The ridge along the east coast will remain in place, and the trough is likely to drift about the eastern part of the continent. Temperatures will remain extreme with the increased likelihood of bushfires in very dry conditions with mainly high based storms continuing except in far northeast New South Wales where there is likely to be more available moisture. The West Australian trough will reform along the west coast and the deepen during Wednesday and early Thursday to bisect the ridge of high pressure along the southern coastline. A front passing close to the southwest corner may trigger isolated coastal showers with its passage.

Rainfall potential
Victoria:  Hot toe extreme conditions mainly north of the ranges, with milder conditions continuing along the coast.  Scattered showers and isolated storms again along the ranges and in the north, becoming more likely in the northeast as the moisture increases with a more northeasterly flow.
NSW: Scattered showers and storms through the east of the state, mainly along the ranges.  Very hot in the far west and south.
Queensland:  Isolated showers and storms near the Gulf and over Cape York, with isolated storms also in the southern areas. Coastal showers becoming more frequent later in the week.
NT: Isolated showers and storms throughout.
WA:  Scattered showers and isolated storms with the trough(s) moving through the state on Wednesday - one to the west near the coast and one further east being nudged northeast by the ridge along the south coast. Isolated storms in the Kimberley.
SA: Isoalted high based storms in the west and north of the state with very hot to extreme conditions continuing.  The trough will continue to lag through the state. Cooler on the coast.
Tasmania: Passing drizzle with a pressure surge and then clearing.

Overview: A weak ridge extends southeast from near to Perth through Tasmania and joins a stronger high in the Tasman Sea. South of this ridge is a series of embedded fronts. A low in the Pilbara anchors a trough through to the southeast of the continent, which has moved into central Victoria during Sunday. Another trough, extending from the Gulf of Carpentaria to central New South Wales has been triggering widespread shower and storm activity, with the most active area in the south. Conditions over the southeast have rapidly warmed through Sunday, with low dewpoints raising the risk of bushfires.

Discussion: A new cell of high pressure will bud off in the Bight, while the ridge along the Queensland coast from the high in the Tasman will broaden and force the trough further west through the state during this half of the week. This trough will continue deepening southward and will begin to affect conditions over the southeast of New South Wales and the north and northeast of Victoria mainly during Tuesday and Wednesday. A weak upper trough will move through the northern Bight during Monday with the trough over the Eucla triggering isolated storms as it moves into South Australia. Isolated storm activity over the north of the continent will continue.

Rainfall potential
Victoria:  Isolated showers and storms developing during the first half of the week and becoming more frequent towards Wednesday, mainly along the ranges.   Becoming warm in the south, tempered by afternoon sea breezes.  Hot north of the ranges.
NSW: Scattered showers and storms within the trough, mainly in the north of the state, possibly a little further west than during Sunday. Risk of isolated showers in the southeast.
Queensland: Scattered showers and storms continuing associated with the trough which will drift further west during Monday & Tuesday. Scattered showers over the far north coast and eastern Cape York.
NT: Isolated showers and storms over the Top End with the chance of isolated showers and storms in the far southwest.
WA:  Isolated storms over the Kimberley and eastern Pilbara. Thundery showers likely in the southern Interior and Eucla with the trough moving east.  Fine elsewhere.
SA: Isolated high based showers with the chance of a storm in the west of the state, advancing east slowly through Monday and into Tuesday. Cooler conditions early on the coast as the high moves east through the Bight.
Tasmania:  Isolated light showers over the south, clearing through Monday. Chance of a shower later in the east.

Overview: The high in the Tasman has strengthened and the ridge along the Queensland coast has anchored, halting the eastward movement of the trough. The trough has also deepened further into New South Wales, and the upper cold pool continues to move across the state from the western border regions. A weak area of high pressure is located to the west of Tasmania, with a series of fronts passing to its south in the westerly flow.  Pressures within the trough across northern Australia beginning to drop. The trough through Western Australia is moving through the east of the state but remains rather inactive.

Discussion: The strengthening ridge along the Queensland coast will edge the trough inland during the remainder of the weekend.  The trough will continue to strengthen southward and the upper cold pool will continue to move towards the New South Wales north coast  / southeast Queensland during Sunday.  The band of high pressure will remain through the Bight and Bass Strait area, and the average pressure over the continent will remain relatively low with 'troughiness' becoming more dominant during Sunday. Conditions over southeastern Australia will become warmer ahead of the trough moving east from Western Australia.

Areas to watch: keep an eye on the upper cold pool moving slowly across New South Wales towards the northern coast....interaction with mid and lower level moisture closer to the coast may trigger occasional strong storms.

Rainfall potential
Victoria:  Becoming warmer ahead of a trough moving into the west early in the week.  The chance of isolated showers and storms over the northeastern ranges as the trough over New South Wales deepens southwards. Fine otherwise.
NSW: Scattered showers and storms over the northeastern parts of the state, more frequent along the Tablelands and the north coast. Isolated storms are possible as the trough deepens through the state, as far south as Eden, but more likely in the north. Fine and becoming warmer elsewhere.
Queensland: Showers and storms continuing within the trough, mainly west of the ranges.  Fine elsewhere with warm to hot conditions away from the coast.
NT: Isolated showers and storms continuing over the northern parts of the Top End, with isolated showers and storms developing in the southwest.
WA:  Isolated storms continuing in the Kimberley, with a slight risk of extending to the Interior at times.  Isolated showers within the trough in the south as it moves through the Goldfields and into the Eucla. Showers may be triggered in the far southwest with the passage of a front through the western Bight.
SA: Remaining dry and warm to hot away from the coast.  Isolated showers and the risk of a high based storm in the west of the state as a trough moves in from Western Australia.  A little cooler on the coast.
Tasmania:  Continuing fine throughout.

Overview: A weak ridge of high pressure extends across the southeast of the continent between the eastern Bight and the Tasman Sea with a ridge building along the Queensland coast.  A trough from the Gulf of Carpentaria to the northeastern corner of New South Wales has become quasi-stationary inland of this ridge. A trough is moving through southern Western Australia and the northern part of the continent lies under the influence of a broad trough. A weak high is approaching from the Indian Ocean with a series of fronts embedded in the westerly flow to its south.

Discussion: A high in the Tasman will strengthen during the weekend, maintaining the ridge along the east coast and stalling the eastward movement of the trough through Queensland which will deepen into New South Wales. The southern portion of the trough over the west will move east, while the northern section will remain anchored to the low over the Pilbara.  An upper cold pool (which was in the western Bight on Wednesday) continues to move steadily across the continent and may be a trigger for shower and storm activity as it nears the more moist environment in the lower and middle levels of the northeastern corner of New South Wales and southeastern Queensland late Saturday and during Sunday.

Rainfall potential
Victoria:  Mainly fine and sunny after early drizzle on and south of the ranges clearing.
NSW: The trough over northeastern New South Wales will become more active during Sunday.  Isolated showers with the chance of a storm on Saturday mainly along the Northern Tablelands and the northeast coast.
Queensland: Isolated afternoon and evening showers and storms inland along the ranges in the vicinity of the trough. A 'dryline' setup associated with t he trough may become apparent during the later part of Saturday west of the ranges.
NT: Isolated showers and storms over the northern part of the Top End.
WA:  Only isolated showers with the risk of a storm east of and near to the trough moving through the state.  Drizzle patches in the far southwest later.
SA: Mainly fine with the risk of isolated showers or high based storms in the west later.
Tasmania:  Mainly fine throughout.

Overview: A weak low has formed over northeastern New South Wales, while the high in the Bight remains slow moving and weakens slightly. The west coast trough has moved inland, drawing a significant amount of moisture onto the continent and is located through the South West Land Division during Thursday night, connecting to a deeper low and upper trough southwest of the continent. Heavy tropical showers over the far north of Cape York and around the Kimberley are rather isolated. A weak area of upper vorticity continues to drift east through the Bight.

Discussion: The high in the Bight will continue to weaken and a new ridge of high pressure will build along the east coast north of the Queensland border. Cool conditions will be maintained over the southeast of the country in a southwesterly flow, moderating over the mainland. The west coast trough will move east through Friday towards the South Australian border, followed by a weakening high near to 35°S. The trough over northern Australia will begin to expand across the northern parts of the continent. The low approaching the western Bight will drift southeast.

Rainfall potential
Victoria:  Isolated showers on and south of the ranges, clearing during Friday.  Warmer north of the ranges.
NSW: A weak trough over northeastern New South Wales will remain largely inactive through Friday.  Mainly dry throughout.
Queensland: Mainly fine throughout excepting the northern parts of Cape York during Friday. A weak trough will deepen through the southeast later Friday and Saturday and may see some scattered showers and storms here during the weekend.
NT: Isolated showers and the chance of a storms over the Top End, mainly in the north and west.
WA:  Isolated showers and storms are likely with the trough as it moves east through the Goldfields during Friday, with seasonal storm activity continuing in the north of the state.
SA:  Drizzle and light showers along the coast.  Mainly fine inland.
Tasmania:  Scattered showers, mainly in the west and south.

Overview: Cyclogenesis over the east coast of Australia and some substantial falls recorded over the past 36 - 48 hours over coastal and tableland New South Wales, along with storms, some severe associated with the trough over Queensland, has made for some very interesting conditions this week for weather watchers. A surface low is located just off the coast, and continues to deepen with strong upper support. The high in the Bight is weakening slightly and extends a ridge to the east through northern Bass Strait / southern Victoria into the Tasman. The west coast trough is deepening down the coast, and a 'deep' low (for this latitude at this time of year) is approaching the western Bight.

Discussion: The low will most likely continue to deepen and move away across the Tasman Sea, although there is a risk that the high in the Bight may ridge eastwards enough to cut the low off. A strengthening southwesterly flow will influence conditions over Tasmania and the southeast of the continent during the next day or so while the high remains slow moving in the Bight. Interaction over the west of the continent during the next 24 hours between the current surface trough and the approaching upper trough and surface low may trigger showers and storms in the western Pilbara and South West Land division, extending east as the trough begins to migrate. Seasonal convective activity over the northern part of Australia will continue.

Areas to watch: an area of upper vorticity in the Bight southeast of Esperance

Rainfall potential
Victoria:  A cool southwesterly flow will continue to trigger overnight and morning showers on and south of the ranges. Mainly dry in the north.
NSW: Showers along the coast, mainly in the central and north of the state, becoming less frequent.  Cool and remaining dry inland of the ranges.
Queensland: Isolated showers over the tropical north. Isolated storms a risk in the northwest.
NT: Scattered showers and storms, mainly over the northwest of the Top End.
WA:  Showers and isolated storms developing in the west, south of about Shark Bay and extending east with the trough. Seasonal storm activity continuing over the Kimberley.
SA:  Cool in the south.  Mainly dry throughout apart from isolated drizzle along the coast Wednesday night.
Tasmania:  Showers, mainly in the southwest. Cool.

Overview: The trough extending from the Gulf of Carpentaria to the northeast of New South Wales has deepened while remaining quasi-stationary through Monday, with widespread showers and storms along its length. An upper trough is moving slowly through the state. The high in the Tasman extends a ridge along the Queensland coast. Another trough, currently moving through southern New South Wales and part of South Australia is also triggering scattered showers, and storms (in South Australia). A strong high is located in the Bight and the west coast trough is slowly beginning to deepen southward. A southwest - southerly flow over the southeast of the country maintained cool conditions with occasional light showers, particularly near the coast.

Discussion: The surface trough over Queensland and northeastern New South Wales will continue to deepen through Tuesday and be forced somewhat westward in the north by the ridge becoming established along the coast, while an upper trough continues moving northeast across New South Wales, and a second trough moves through the state.  Widespread showers and storms will continue inland of the Queensland coast, over southeast Queensland and northeast New South Wales through Monday night and Tuesday.

The high in the Bight will maintain its strength and move east near to 40°S extending a ridge to its east which may help cradle the trough over eastern Australia, while the west coast trough will deepen near to he coast.  A significant upper trough is approaching the west of the continent.

Areas to watch: near northeastern New South Wales / southeastern Queensland for interaction between the deepening upper trough and the surface trough(s) during Tuesday, particularly if the second trough through New South Wales becomes absorbed. Some heavy falls are likely if cyclogenesis occurs in the area.

Rainfall potential
Victoria:  Isolated showers on and south of the ranges.  Fine in the north but remaining cool throughout.
NSW: Showers and storms, mainly over the northeast of the state, with some showers with the chance of a storm associated with the passage of a second trough through the southeast and central districts - clearing behind.
Queensland: Widespread showers and storms extending from the Gulf of Carpentaria to the southeast corner, becoming widespread in the southeast, with the likelihood of some moderate to heavy falls. Scattered showers and storms over Cape York and the northeast tropical coast.
NT: Scattered showers and storms, mainly over the northwest of the Top End, with isolated showers in the south mainly Monday night.
WA:  Isolated storms over the Kimberley and eastern Pilbara with drizzle patches in the south clearing.
SA:  Mainly cool conditions in the south with showers, mainly along the coast contracting east as the high moves through the Bight.  Isolated showers and storms in the northeast Monday night contracting northeast Tuesday and clearing the state.
Tasmania:  Scattered showers continuing mainly in the west and south of the state.

Overview: A trough extends from the Kimberley to the southeast of the continent and is triggering scattered showers and storms over South Australia.  A weak high is located in the Tasman and extends a ridge along the Queensland coast. A trough extends along the west of the ranges in Queensland with a clearcut moisture boundary (dryline setup?).  A stronger high is approaching the western Bight. A front is crossing Victoria and Tasmania with only scattered showers through Sunday afternoon.

Discussion: The weakening front and trough will merge as they continue to move through New South Wales during Sunday night / Monday and is likely to trigger showers with isolated storms when it moves into more favourable areas in the northeast. The ridge along the Queensland coast will slow the eastward movement of the trough during the next day or three. The high will continue to move east through the Bight along a 'summer synoptic' path and the west coast trough will commence deepening southward. The southwesterly flow over the southeast of the continent will maintain cooler conditions for the next day or so and there may be further shower activity during Monday with the passage of another trough.

Areas to watch: the latitudinal cloud streak in the Bight on Sunday should be watched over the next 24 hours for further migration / development.

Rainfall potential
Victoria:  Scattered showers and cool conditions on and south of the ranges.   A period of more frequent shower activity as another trough crosses the state Monday.
NSW: Isolated showers and storms developing as the trough moves into the northeast of the state later Monday. Showers developing over the southern parts with the passage of a second trough.
Queensland: Scattered showers and isolated storms likely along the trough extending along the west of the ranges and then stalling during Monday, with possible patchy rain developing mainly in the south. Showers and storms to continue over Cape York.
NT: Showers in the southwest clearing through Monday.  Scattered showers and storms mainly over the western Top End.
WA:  As a new trough deepens along the west coast, showers and isolated storms are likely through parts of the Kimberley, Pilbara, Gascoyne and towards the southwest. Lingering showers or drizzle along the south coast should clear Sunday night.
SA: Showers over the south in the onshore flow should decrease during Monday.   Isolated storms in the northwest are a risk with the presence of a trough lingering in the area.
Tasmania:  Scattered showers continuing over much of the state.  Risk of snow over higher peaks.

Overview: The weakening high has moved quickly across the southeast and is located just off the New South Wales coast and has extended a ridge along the Queensland coast. The trough through inland Queensland, although inactive during Saturday, has deepened into northern New South Wales.  The trough in Western Australia is moving east and is located near the border, triggering isolated storms in the Interior. A front is passing just to the south of the state through the Bight. A high is approaching the west. Seasonal storm activity continues across northern Australia, but is isolated.

Discussion: The high will move eastwards into the Tasman and strengthen the ridge along the Queensland coast. The front will capture the trough and move through South Australia and much of the southeast during Saturday night and Sunday with scattered showers and isolated storms. The trough through Queensland and northern New South Wales will deepen but remain largely inactive away from the tropics. The high will ridge around into the Bight while the west coast trough will redeepen down the coast of Western Australia.

Rainfall potential
Victoria:  Scattered showers and isolated storms during Sunday as a trough passes across the state.  Strengthening northwesterly winds ahead of the trough, shifting cooler southwesterly from the west.  Scattered showers on and south of the ranges behind the change.
NSW: Isolated showers and storms near to the trough moving into the west and through the southern parts of the state.
Queensland: Isolated showers and storms over the tropical north and central inland.  Dry elsewhere.
NT: Isolated showers and storms over the Top End, with the chance of showers and storms in the far southwest.
WA: Isolated showers and drizzle along the southern coast.  Scattered showers and isolated storms in the northeast quarter.
SA:  Isolated showers and the chance of a storm with the passage of a trough through the state Saturday night and Sunday.  Showers along the coast following the wind change.
Tasmania:  Showers in the southwest becoming more general through Sunday, before contracting to the west and the south after the passage of a front.

Overview: Strong southwesterly winds have been abating somewhat during Friday over the southeast of the country.  Snow falling has been reported through Thursday night and Friday morning to 400metres with much of the alpine areas in the southeast and Tasmania receiving reasonable falls. A high has become stationed in the Bight to the east of the deepening west coast trough, while the front and trough that passed across the southeast during Thursday is moving off the Queensland coast during Friday night. Scattered seasonal activity continues particularly over the northwest.

Discussion: A cold night inland over the southeast under clear skies with frost patches likely with the colder air remaining near the surface, a remnant from the past 2 days. With a strongly zonal flow in the upper levels, surface systems will move east more rapidly than over the past few days, with the high progressing across the southeast during Saturday and the west coast trough migrating eastward towards the South Australian border. The trough over Queensland will drift slowly west as the high in the south moves east and extends a ridge along the Queensland coast. Widespread showers and storms are again likely over inland Western Australia.

Areas to watch: an interesting area of moisture in the Timor Sea seems to be migrating southwest in the upper layers........

Rainfall potential
Victoria:  A cold night inland with likely frost patches. Scattered showers in the south, mainly along the coast, clearing to the east. Mainly fine in the north with patchy morning cloud in the south clearing later.
NSW: A cold night away from the coast with the likelihood of frost patches in the south and along the ranges. Showers over the alpine areas clearing. Stronger winds in the south abating during Saturday.  Mainly fine elsewhere.
Queensland: Showers over Cape York, becoming more widespread along the exposed coast further south later Saturday. Fine elsewhere.
NT: Isolated showers and storms over the Top End. Isolated showers and storms in the far southwest.
WA: Isolated shower and storm activity over the Kimberley and extending through the east Pilbara, Gascoyne and Interior and the trough moves east. Storms are likely within and to the east of the trough.
SA:  Increasing patchy cloud in the west with the risk of a shower or storm developing. Remaining mainly dry after a cold night in the south and east.
Tasmania:  Southwesterly winds becoming northwesterly later Saturday as the high moves east and winds slacken.  Showers becoming less frequent over most areas and clearing from all but the west and south.

Overview: The low has continued its eastward drift south of Tasmania and has deepened from 983hPa to 970hPa in the last 24 hours, tightening the pressure gradient and bringing gales, showers, brief hail and some sleet to the southeast of the country.  Wilson's Promontory recorded a gust of 117kmh. The high in the Bight continues to move only slowly, ridging to the north and south of the low, while there is no discernible ridge along the Queensland coast. The trough now lies through northeastern Queensland and the trough in Western Australia has deepened along the west coast.  Moisture continues to build up over inland Western Australia.

Discussion: As the high moves southeast during Friday and a new cell of high pressure develops over the Bight, the strong southwesterly flow over the southeast will begin to moderate through Friday, although stream showers will continue with snowfalls likely over higher parts of the alpine areas (especially Tasmania). The west coast trough will continue to deepen (as an enclosed low) through Friday and begin to move east triggering isolated showers and storms. Seasonal storm activity will continue over northern Australia.

Rainfall potential
Victoria: Showers continuing on and south of the ranges, but becoming less frequent, with the chance of brief sleet or snow over the higher peaks, mainly on Thursday night. Unseasonally cold southwesterly flow with windchill in the single figures in the south! Mainly fine north o f the ranges.
NSW:  Showers mainly on the Southern & Central Tablelands with the chance of brief sleet or snow at higher levels Thursday night & through Friday. Showers along the coast contracting north and clearing with the weakening of a trough.
Queensland:  Showers along much of the Queensland coast, excepting for the southeast corner.  Showers and storms more frequent in the northeast tropics. Cloud increasing in the west but remaining mainly dry.
NT: Seasonal showers and storms over the Top End with isolated showers possible in the far southwest.
WA: Scattered showers and storms over the Kimberley, extending to the northern Interior and Gascoyne.  Showers and isolated storms in the southwest and Goldfields, moving east with the trough.
SA:  Increasing cloud in the west but remaining mainly dry.  Showers over the southeast corner on Thursday night, clearing through Friday.  Strong southwesterly winds moderating.
Tasmania:  Showers and rain periods with the chance of snow at higher levels, decreasing to showers later Friday but with conditions remaining cold.

Overview: The low in the Bight has commenced a southeast drift but is remaining strong (983hPa at 4pm).   The cloudband that passed across Victoria during Wednesday associated with the low in the Bight gave reasonable falls of between 5 and 20mm mainly south of the ranges accompanied by strong winds.  A front is approaching the southeast of the country.  The trough located through eastern Australia has moved steadily east and is now located in northeast New South Wales and eastern Queensland to the west of the ranges. The ridge of higher pressure along the Queensland coast is virtually non-existent.

A heat low in Western Australia is deepening and digging southwards down the west coast. while a ridge of high pressure continues to extend along the southern coastline. Seasonal storm activity continued through the Kimberley, Northern Territory and tropical Queensland and associated with the westward extension of the trough.

Discussion: During Thursday, the eastern extension of the trough will move out of New South Wales and into the Tasman Sea along much of its length. The lack of a marked ridge along Queensland coast will assist the eastward movement of the trough. The low in the eastern Bight will continue its slide to the southeast, but will likely redeepen during Wednesday night and Thursday. A front crossing Tasmania and southern Victoria during the day will bring even colder conditions that seen today with the snowline descending to near 4,000'ASL, and the trough is likely to also influence conditions along the south coast and Southern Tablelands and alpine areas of New South Wales Thursday.

The west coast trough will deepen and bisect the ridge of high pressure in the western Bight, with a new cell likely to bud off in the central Bight. Once again there is a significant buildup of tropical moisture in the interior of the continent which will feed southeast with the next trough and frontal system to move through our longitudes.

Rainfall potential
Victoria: Scattered showers and isolated storms with the chance of hail, mainly on and south of the ranges, becoming more frequent on Thursday with the passage of a front through Bass Strait influencing near areas. Chance of sleet or snow over higher parts especially with this second cold surge. Cooler conditions with fresh southwesterly winds.
NSW:  Showers in the southeast with the chance of a storm, remaining showery with the chance of a storm along the south coast and adjacent ranges during Thursday. Mainly fine in the remainder of the state with milder temperatures - there is a chance of sleet and possible light snowfalls over the higher parts of the alpine areas.
Queensland:  Isolated showers and storms along the trough and to the east and north of the state, contracting northeast through the period. Remaining mainly dry west of the trough
NT: Patchy rain clearing to showers in the south with seasonal storm activity in the north, mainly near to the trough.
WA: Scattered showers in the Interior with seasonal storm activity continuing through the Kimberley.  Isolated storms along the west coast near the trough, with isolated showers and the risk of a storm in the Goldfields and southern Gascoyne.
SA:  A solar eclipse over a narrow path across the state Wednesday evening <g>. Patchy light rain in the far northwest with cooler conditions in the south and the chance of a shower along exposed coasts, extending inland and becoming more frequent.   Increasing showers during Thursday especially in the southeast with the passage of a front.
Tasmania:  Showers continuing across the state, particularly in the west and south, with the chance of a storm.  Some locally heavy falls likely.  An increase in shower activity with the passage of a front tomorrow with the chance of light snowfalls over higher parts.

Overview: The trough over Victoria and southern New South Wales moved east through Tuesday with scattered showers and isolated high based storms starting numerous fires across inland areas with only scattered light falls recorded. This trough extends through western Queensland and to the east Pilbara. The low in the Bight remained quasi-stationary during the past 24 hours at between 982 and 984hPa.

A broad high to the east of the continent extends a weak ridge just east of the Queensland coast. Moisture from the Timor Sea and near to Indonesia continues to feed across the continent along the trough. Seasonal storms continue across Cape York, the Top End and the Kimberley.

Discussion: The trough will move east through eastern Australia during Wednesday, triggering showers and storms near to the trough axis and to the east, mainly high based inland and in the south. The ridge of high pressure along the Queensland coast will strengthen and help to slow the progression of the trough in northeast New South Wales and through Queensland. The southeast will see cooler conditions as southwesterly winds become established.

The high to the west of the continent will ridge along the southern coastline with fronts being directed towards the southeast and away from Western Australia.  The west coast trough will deepen southwards along the coast, bringing hotter weather to the far west.

Rainfall potential
Victoria: Stream showers likely on and south of the ranges as the southwesterly flow becomes established over Victoria during Wednesday and the low moves east.   Mainly dry north of the ranges, but temperatures becoming milder.
NSW:  Showers and storms associated with the trough moving through the state and into the northeast, where it will become quasi-stationary.  High based and often dry storms are likely inland and in the south, with heavier falls in the northeast and along the Northern Tablelands. Winds shifting cooler southwesterly behind the trough.
Queensland:  Isolated showers continuing along exposed coasts with seasonal storm activity over Cape York. Scattered showers and storms developing over the south during Tuesday night and into Wednesday, and extending into central districts east of the trough during Wednesday.
NT: Scattered showers and isolated storms in the northwest and southern and central parts near to the trough.
WA:  Widespread shower and storm activity in the Kimberley, and extending into the northern Interior and the Pilbara. Mainly dry in the south.
SA:  Isolated showers over the southeast corner, becoming mainly fine later.
Tasmania:  Showers and the chance of a storm in the northeast Tuesday night and early Wednesday. Northwesterly winds shifting cooler southwesterly later with the chance of snow showers over higher parts, particularly later Wednesday / Thursday.   Scattered showers becoming more widespread throughout Wednesday.

Overview: A slow moving low (982hPa) has taken up residence in the Bight west of Tasmania, semi-cutoff by the ridge from the high to the southwest of Perth, and is moving only slowly southeast.   A trough extending from the Kimberley to Victoria is moving only slowly through the southeast and has produced light mid-level showers in southern Victoria and through Bass Strait, followed by a front associated with the low, the latter currently located in the southwest of Victoria. A weak ridge of high pressure lies off the Queensland coast with isolated showers along the northeast  coast. Seasonal storm activity continues in the Kimberley and northwest Territory, while showers along the southern Western Australian coast are generated in a moist onshore flow.

Discussion: The low in the Bight will remain rather deep during the next 24 hours and continue a slow drift to the east, cradled by ridges of high pressure to both the north and the south. The trough will drift into New South Wales (with the southern portion through Victoria weakening) and become quasi-stationary, while the front will continue its movement across the southeast and into the Tasman Sea. The ridge off the Queensland coast will strengthen, with the trough remaining inland during Tuesday and Wednesday.

The high to the west of the continent will ridge in along the southern coastline and the west coast trough will deepen southward near to the coastline. Mid and upper level moisture will continue to feed in across the continent into the east and southeast from the Timor Sea and near to Indonesia.

Rainfall potential
Victoria: Isolated middle level showers, with the risk of a storm, near to the trough and front,  moving through Monday night and Tuesday. Cooler conditions later Tuesday / Wednesday with isolated showers.
NSW:  Isolated showers and storms, mainly along the ranges in the north and along the north coast, where moisture availability is greater.  Mainly dry inland with the wind change with cooler conditions to follow.
Queensland: Isolated showers along the northeast coast and occasionally over exposed parts of the coast as far south to near Fraser Island. Isolated storms near to the trough in the central and southeast of the state.
NT: Scattered showers and isolated storms, mainly in the northwest Top End and the Tennant Creek area near to the trough. The risk of a storm further south.
WA:  Showers and storms continuing over the Kimberley and through the northern Interior. Isolated light showers or drizzle along the southwestern corner and southern coast, contracting eastwards and slowly clearing.
SA:  Isolated showers and the risk of a storm in the east and northeast clearing out of the state overnight Monday.  A few showers over the southwest coast during Tuesday.
Tasmania:  Strengthening north - northwesterly winds with the approach of a front. Showers becoming more frequent in the west Tuesday, with cooler, windy conditions to follow later in the week.

November 2002 Forecast Outlook, Discussion & Report page