April 2001 Forecast Outlook, Discussion & Report Page

Victoria
Date Name

Information
30 Clyve Herbert It looks better over your way (SE NSW) with the prospect of a strengthening southeast to easterly flow developing overnight and then the Tasman Sea low slipping southwest towards northeast Tasmania during the week, could be some good falls about the Wollongong escarpment.
30 Clyve Herbert I couldn't help being surprised by the forecast for Victoria today and the rest of the week, fine, fine, fine, and fine - ok I must have missed something, or is that an upper low lurking east of Broken Hill and moving south southwest with a respectable amount of mid and upper cloud lounging around that area! With a few thunderstorms thrown in as well. Although a bit of a wish forecast it really does look rather interesting for the southeast of Aus over the next couple of days, although lacking a bit of cold air aloft >700hPa, there is a reasonable amount of mid and upper level moisture. Also looks like the dry season has commenced over the Top End with a marked retreat of the ITCZ over the past several days. 

Also got a record wet April here at Leopold with 173.5mm, its been an interesting year so far with April being the second month in succession above 100mm (March 103mm) all up that's 276.5mm and all of this came in just 5 raindays, and that's almost half of my annual average.

Images relating to the April rain event in Victoria
28 Lindsay Smail SPECIAL REPORT ON RAIN EVENT 21-24 APRIL, 2001

"Rain from the east - three days at least". That's what the old adage says, and for the second time in less than a month it's been proven true in the Geelong region.

Starting around 12.30 am on Saturday 21st, rain began to fall in Geelong. By 9 am, 8 mm had been registered at Grovedale. Continuing light showers fell for the rest of the day, with some respite during Saturday afternoon.

But in the early hours of Sunday 22nd it began to get heavier and more constant. Around 3.30 am heavy rain commenced, so that by 9 am the 24-hour total had reached 52.8 mm, a record for an April day in the district. Not letting up, the downpour continued right through until 6 pm when there was a lull for two hours in which only light drizzle persisted.

By 6 pm on Sunday 22nd the progressive 9-hour total had reached 52 mm and more was approaching.

Meanwhile news arrived that the Otway and Moorabool water catchments were also benefiting from the deluge. Mt Sabine in the West Barwon catchment reported an incredible total of 478 mm from 9 am Saturday to 9 am Tuesday, triggering flood warnings for Geelong in the following days.

Geelong's 72-hour total to midnight on Monday 23rd reached 165 mm and even more rain was forecast, albeit lighter, for the next day. When the rain stopped around 9.30 am on the 24th, Geelong had received more rain than four times the April average and almost one third of our yearly normal.

What was the reason for this freakish circumstance? Geelong Weather Services believes that, while the rainfall totals were freakish, the causes were not. Basically the reason for the high totals in the region was the growth of a low pressure trough over eastern Victoria which developed a slow-moving wrap-around cloud band moving from the east and southeast over the Bellarine Peninsula, Geelong and the eastern Otways. The system had been made more than normally unstable with the effects of an upper level cold pool which had been fed in from the southwest in the previous few days.

The westward-moving winds brought so much rain to the Otways-Surf Coast region because the lie of the coast is directly perpendicular to the wind flow, causing rapid lifting of the air mass and the resultant precipitation.

Normally we could expect such an event to happen once or twice in a year. But we have had three such events with stalled low pressure systems in the last seven months.

Some rainfall totals for the event (a period of 91 hours) up to 9 am Tuesday 24th were: Mt Sabine 478 mm, Mt Cowley 414 mm, Benwerrin 310 mm, Boonah 274 mm, Weeaproinah 227 mm, Aireys Inlet 209 mm, Highton 180 mm, Forrest 177 mm, Leopold 172 mm, Grovedale 170 mm, Anglesea 164 mm, Manifold Heights 161 mm, Hamlyn Heights 158 mm, St Albans Park 153 mm, Lara 150 mm, Meredith 146 mm, Corio 144 mm, Avalon 134 mm, Bannockburn 133 mm, Cressy 123 mm, Birregurra 102 mm, Colac 101 mm, Scotsburn 94 mm, Laverton 92 mm, Lal Lal 88 mm.

Lindsay Smail and the Geelong Weather Services
27 David Jones It might not be quite as spectacular as what is happening in the northern states, but the Melbourne radar and local satellite pictures show the rapid development of an area of rain, with embed convective activity on a meso-scale wave on the weakening front. There is the indication that a meso-scale low has formed on this front, which until three hours ago looked like it could be rainless in Melbourne. Interestingly, this has been missed entirely by the models, and to tell the truth no simple explanation comes to mind as to what has caused this sudden small scale development. Small scale features like this tend to highly transient in nature, but with its relatively slow rate of movement, and relatively high rainfall rates, there is the potential for some moderate(10mm+ falls).It is always "fun" to see the models fail at short notice occasionally.
27 Clyve Herbert A check of the sat pic for south-eastern Australia shows what appears to be a small weak wave low just west of Ballarat, although not very well defined it's worth keeping a check on over the next 6 hours, also the rather large mid and upper level cloud area over SA looks interesting too and is aligned along the Subtropical jet and moving eastward - should bring some patchy rain to the weather starved SA regions today.
26 Clyve Herbert I noticed some rather organised activity sitting off the north coast of the Top End this morning, appears to be connected to a trough extending from New Guinea, and moving towards the west - also I suspect the presence of an pressure outflow set up extending from the Coral Sea, may be the odd storm about tomorrow too

Victorian Weather Glass

Keep an eye on what's happening in Victoria - IR, MSL, radar & link to AWS observations - all on one page.
24 Nick Sykes Overnight another rainband has moved up over the metro area with totals since 9am yesterday approaching 50mm in some suburbs (Kilmore Gap, sitting on 86.8mm). It appears that a new low centre or trough   has formed just to the SE of Melbourne, winds have turned northerly to the east of Melb and over Western Port, while over most of the metro area strong SW winds are blowing. Pressures are also much lower than last night. Seems the main area of rain will concentrate on the east Central district, Gippsland today, with heavy falls still possible.
23 Lindsay Smail Almost non-stop since 12.30 am on Sat 21st. Barwon River flooding at Geelong expected to peak around midday Tuesday with consequent widespread damage to low-lying industries, caravan parks, houses, roads and bridges. Record-breaking rains have occurred: 65-hour falls to 5pm 23 April: Grovedale 150 mm, Aireys Inlet 184, Mt Duneed 147. Continued lighter falls also expected overnight and on Tuesday 24th.
23 Andrew McDonald Balook (30km S of Traralgon in East Central Vic) has had 395mm from 9am Saturday until 7pm Monday night (58hrs) and Mt Sabine in the Otways (in SW Vic about 8km N of Lorne) has had 385mm in the same time period.  Airey's Inlet is approaching 200mm for the event as are several other stations in SW and SE Vic.
22 Luke Garde Clifton Springs has received a nice total of 55mm over night and since 9am (till 12pm) this morning we have had 36mm and the rain is still falling quite hard.
22 Blair Trewin Weeaproinah is not ideally situated for extreme rainfalls in an E/SE type situation; I will not be surprised if Tanybryn has gone beyond  200, possibly well beyond. Unfortunately it only reports monthly so we'll have to wait until early May to find out.

The Melbourne catchments have done well out of this too; 107mm at Mt. Baw Baw (and 131 at Erica, which is vaguely indicative of catchment conditions even though I don't think it's actually in the  catchment). There were three-figure falls scattered through Gippsland, with 157mm at Genoa, as well as on the far south coast of NSW (Eden 118).

The north-south contrast through the Melbourne metro area is interesting; most of the northern suburbs are in the teens (which means they got little or nothing from this morning's rain - what they got fell in yesterday's thunderstorms), whilst southern suburbs are near or above 50. I live in Heidelberg, which was on the northern boundary of the (near-stationary) rain area, and had the odd experience of spending most of a 100-minute run in sunshine and rain simultaneously (normally such conditions only last for a few minutes at most, in short-livedshowers).

Update - 284mm reported at Mt. Sabine. If confirmed, this would be (from memory) the fourth-highest 24-hour total on record in Victoria. There has also been a report of 180mm at Cowwarr Weir, in Gippsland.

Flood warnings are in effect for the Barwon and Thomson Rivers (haven't seen those for a while!), and for streams draining the Otways.

22 Jane ONeill

...and these figures are interesting:
44.4mm Mt Dandenong
2.8mm Scoresby
Precip & middle level cloud is moving from the ENE (with a local surface & lower level flow from the S) which makes Scoresby effectively rain-shadowed by Mt Dandenong for this event even though the recording stations are  only a stones throw apart (<9km from Mt D lookout)
22 Lindsay Smail 24-hour totals recorded to 9 am across the region: Geelong CBD 39 mm, Grovedale 42.8, Mt Duneed (BoM) 47.2, Hamlyn Heights 55, Leopold South 53.1, Inverleigh 34, Paraparap 76, Aireys Inlet (BoM) 87.8, Apollo Bay 37, Anglesea 62, Meredith 63, Cape Otway (BoM) 16, and good old Weeaproinah 126

BoM 24-hour figures for Mt Sabine 284 mm, Mt Cowley 251 mm and West Barwon 140 mm, all in Geelong Water Catchment should make the Water Board happy. Bureau flood warning issued at 10.14 am.
18 Nick Sykes This system is looking very interesting, and if a few things come together we could be looking at very heavy rains, if not flood rains in parts of SE Australia (though the dryness of late may prevent this) Looking at the latest sat pic you can see the cloud associated with the strong thermal trough to the SW of Victoria.

All the models have some form of low pressure system forming in the SE, and most of them have it producing very heavy rainfall. The position of the low is very important to where and how much rain we will see. The BOM are favouring a position in Eastern Victoria/Bass Strait. This will see the heaviets rains dragged into Gippsland. Further east and SE NSW will see heavy rain.

The models have this system been very slow moving with it still affecting Vic on Tuesday.
Certainly a system to watch.

Also interesting is the longer term. The models are hinting at potentially a strong cold outbreak towards the end of next week. The synoptic situation should be favourable with the low weakening the high pressure ridge over Australia and a strong high to the SE of NZ and to the west of WA. Any fronts should have no problems moving north.
18 David Jones It is still a couple of days, off but the "models" are all falling into line in predicting major cyclogenesis over SE Australia over the weekend. The lead up to this event makes for "interesting" viewing as a major thickness trough (tongue of cold air) - the makings of which can currently be seen south of the bight - "advects" north to lie near the Victorian coast by Friday night. Guess the real interest in the lead up is the intensity of the thermal trough - freezing levels over Bass Strait near 1200m - and the fact that the thickness trough initially coincides with very high surface pressures (~1028hPa+), and a strong high near Tasmania. The air associated with this thermal trough is very cold for this time of year, which could make for some very low overnight temperatures, particularly over Tassie and highland snow.

Anyway, through the weekend, a "classical" easterly type dip develops as the baroclinic zone on the north side of the trough amplifies, with rapid development of a low over Victoria in the ~36 hours to Sunday night. The low/trough then looks like remaining situated near Victoria for a few days, before being captured sometime next week (of course this is a long long long way off in model land).

Anyway, I guess the things to watch for with this system will be;
Possible thunderstorms over NSW on Thurs/Fri ahead of the strong thermal trough (current forecasted ToTTot values 50-60).
Snow and cold temperature over Tassie Thurs/Fri and prob cold night temperature for parts of Victoria.
Widespread rain developing over Victoria and adjacent areas over the weekend as the low develops. 

Cut-off systems like this one seem to be predicted quite reliably by the models, but the exact weather experienced is very sensitive to the placement of the low centre.
18 Nick Sykes A nice looking morning in Melbourne today. The early inversion has broken and the northerly is in, and it's pretty warm. There is bit of altocumulus around, and a "mackeral sky" patch. Overnight, some thunderies developed in parts of Victoria and an extensive area of storms developed to the south of the state. The BOM now have storms on the forecast. LI's around -2 are progged and with the high temp, 26 forecasted, storms are looking better. Change doesn't look like coming through till tonight which could be a worry, but should be a day to keep an eye on.
17 Clyve Herbert Hi all weather lovers.

Wednesday 18.04 01 to Saturday 21.04.01

AUSTRALIA - A DISCUSSION
For those of us that are looking for a bit of weather action over south-eastern Australia at least, the baric ridge which has been pestering the south coast of virtually all of Australia over the past two weeks is now starting to break down,this will allow more active and frequent frontal activity to affect southern SA, most of south-eastern Australia and Tasmania. A strong high presently building southwest of Perth will be slow moving and will progress towards the western Bight by Friday, this high however will drive a good deal of cold air into south Australia and all of the southeast of the continent from Friday and into Saturday.The interaction of cold air moving across the relatively warm southern ocean fringing the southern coasts of SA and Vic will increase the instability factor and there is a possibility of major cyclogenesis near to the southeast of Australia over Saturday and Sunday, especially if a marked cold pool is advected across these regions later Friday and Saturday. All this put together may lead to significant rainfall mainly over Victoria,Tasmania and the highlands of NSW, depending on the location of this possible development if occurring further north than 35 degrees over the southeast of the continent may lead to moist onshore southeast to northeast flows over NSW with heavy coastal rain possible. The tropical north will see the present cyclone bring some late season rain over the next two days and with some showers and storms until the weekend, patchy rain may spread southeast from TC Alistair bringing some  mainly light  rain across the centre over the next two days. Colder conditions will become established over the southern half of Australia from Thursday and persist until next week.Highland areas of Tasmania,Victoria and southern NSW should see some snowfall especially from Friday 20/04.

VICTORIA.....Mild to warm conditions on Wednesday ahead of a cold front with showers and isolated storms mainly in the south and along the dividing range,cooler conditions to follow with a few showers mainly coastal and mountains. Thursday will be cool to mild with a few showers mainly over the southwest and along the mountains, Friday will see another cold front with showers tending to rain at times and strong winds, showers should also affect northern areas and colder conditions generally to follow with highland snow especially above 1150m, showers should persist on Saturday with longer spells of rain possible as a cold trough stalls over southeast Australia, risk of heavy falls and possible thunder.

GEELONG OUTLOOK.
Wednesday 18.04. Partly cloudy and rather warm, strengthening north wind, showers later with a cool change, possible storm.
Thursday.  19.04. Very cool morning - a shower or two mainly in the afternoon, a little milder after midday - fresh winds.
Friday. 20.04.  A few sunny breaks in the morning then strengthening northwest winds and showers ahead of a gusty colder southwest change, chance of a storm, cold night to follow.
Saturday 21.04. Rather cold with showers possibly tending to longer spells of rain, some showers may be heavy.

Regards Clyve Herbert and Lindsay Smail and the Geelong Weather Services.(NMP)
17 Michael Thompson (NSW) Both NGP and GASP are going for a nice low cradled by high pressure on Saturday, this will provide a great moisture feed into the system. MRF is trying for a more East Coast low scenario, which is not too good for storms, but better for heavy rain in the Illawarra.. ECMWF has a similar prognosis to NGP and GASP,  just delayed a little.

Sticking with GASP and NGP,  on Sunday the low should start drawing cooler and drier air in behind it, this may lead to some interesting storm possibilities in NSW, perhaps even SE Queensland. The jet stream is currently plotted in a rather ideal setup too.
17 S G (SA) Interesting upper level low starting to show up on most forecast models for Friday this week and it's also rating a mention in South Australia's and Victoria's weather notes. Adelaide looks like it will be on the far west of the upper disturbance reducing our chances of some interesting weather although it is still possible. The system may attract a surface low from the south or produce it's own surface low on Friday. NOGAPS are forecasting a surface low to be positioned in Bass Straight. If the surface low does develop with the upper level system things could get rather interesting.
17 Clyve Herbert I noted that the BOM have named this system TC Alistair on the 0400 chart. A look at radar at 0900, a weak centre could be discerned about 90 to 120klm north, northeast of Melville Is, or due north of Point Jahleel, it is possible to see rain radar echo's starting to wrap around the apparent centre. This TC seems to be moving at towards 265degrees, the system has become smaller overnight with the upper divergence field appearing a little weaker. It will be interesting to see if this development "vacuum cleans the Top End of the remnants of the wet season.
16 Clyve Herbert This tropical system is now looking very nice and appears to be drifting towards the southwest , the upper divergence is very good but low level convergence could be better, this tropical low started I believe north of 5 degrees south and at last call was still north of 7 degrees south, this is a long way north of normally maturing TC's but not unknown, at the moment I would be a little concerned for coastal areas north of Darwin and even for the Darwin district.
15 Clyve Herbert Hard to find any mention of the upper low over Victoria today, but it's better than clear skies -   some nice thick cirrus and even some alto cu  which looked good in the sunset, also the weak area of convergence is persisting north of the NT been there on and off for the past few days, at last though the baric ridge across southern Australia is starting to weaken which should start to allow better frontal activity across south-eastern Aus this week.

Its interesting to see a small vorticity centre spinning up just west of King Is at 2200hrs, this small area of vorticity is only about 50klm across and is above 500 hpa appears to be moving east southeast, a small rain band has started up near Mortlake with 10 to 20mm/hr now showing up, the area of high cloud across Vic appears to be high level baroclinic activity associated with the upper low.
12 Clyve Herbert SOSE has now become an extra tropical system north of New Zealand, however the mass of cold air running through the Tasman (and developing into a low) may pick up former TC SOSE over the next 12 to 24 hours - if this occurs we might see Sose explode into a major extra tropical low off the east side of New Zealand.
11 Ashton Anderson (Tas) ..when I went out this morning the temp was around 5.0 (0600h) Just arrived back in and it's now 4.2 (1645) the pressure has risen to 1019 from 1012.5 and we have had 17.00mm rain.
Today I had to go to the top of Mt Wellington at about 1000h. About 600m from the summit it WAS snowing, full on, the road had not iced over but the scrub was covered and the wipers struggled. Quite amazing. WHEN i returned home just now I took the dogs for a run in the bush. A track that descends to a valley about the 400m level. And hail/sleet/frozen rain what you will. Back to my place 550m and swirling snow. Both Mt Wellington and Collins Cap are covered down to the 600m level. Snow is falling below that but not settling. In fact here it
omes here again!
10 Clyve Herbert Wednesday 11.04.01 to Saturday 14.04.01

Hello weather lovers.

AUSTRALIA - AN OVERVIEW
The strong baric ridge continues to dominate the southern coastal areas of Australia, this ridge extends from southwest of Perth then meanders across the northern Bight into southern Victoria and then across the Tasman to the North Is of New Zealand. There are however signs of a temporary weakening of this ridge in the vicinity of south-eastern Australia and Tasmania during Wednesday and Thursday with the approach of a marked trough and cold front. Overnight Wednesday and early Thursday the ridge over Victoria will collapse with the main high pressure centre consolidating over the central Bight and then extending a ridge southward to the southern ocean, this will aid in the catapulting of a 500hpa thermal trough north-eastward into south-eastern Australia and the Tasman Sea. This area of cold air will pass over the relatively warm waters off Victoria and then into the warm Tasman Sea this set up will favour general showers and isolated storms especially over eastern Bass Straight and the western Tasman Sea, with general showers over southern and mountain regions of Victoria and all of Tasmania. The marked cold air field at this stage appears to favour Tasmania and eastern Bass Strait but there is a risk of a brief invasion of cold air into central Victoria later Wednesday.

For the remainder of Australia, patchy rain over south-western WA from ex TC Walter should contract southeast and peter out, further showers and isolated storms should affect north-eastern NSW until the arrival of a major pressure surge later Thursday with showers then contracting to the east coast. Very cold nights should affect much of Victoria from Wednesday night and spreading into most of NSW Thursday with plenty of early frosts until at least Friday morning. Severe cold will also affect Tasmania from early Wednesday with general highland snow and severe frost especially in sheltered eastern areas. A strong high pressure cell will then affect much of south-eastern Australia from later Thursday and moving into the Tasman by Friday and Saturday. A warming trend is then expected across south-eastern Australia from later Friday and Saturday. The outlook for Sunday and beyond sees what appears to be a major trough extending from WA into south eastern Australia with strengthening north winds before a change possibly later Sunday or Monday. Only isolated late wet season storms can be expected over the top end otherwise it will be mainly dry.

VICTORIA.....A trough and cold front should move through Victoria on Wednesday with showers mainly in the south and along the ranges, some heavy showers are possible especially near the Otways and over the southeast of the state. Strong south to southwest winds will affect coastal areas especially east of Cape Otway. Showers will continue overnight in the south and about the highlands with snow extending to at least 1200m later Wednesday and to lower levels overnight Wednesday especially in the east of the state. Isolated thunder and local hail is possible mainly east of Port Phillip Bay, isolated water spouts east of Wilson Prom with a very slight risk over Port Phillip and central Bass Strait. A strong high pressure system should then move towards Victoria on Thursday with showers becoming more isolated, very cold mornings will occur especially over inland areas on Thursday and Friday Morning with frosts in sheltered areas. As the high pressure system shifts eastward on Friday winds will become lighter and tend more easterly, Saturday and Sunday should become milder with warm conditions returning to northern areas, some fog should be experienced over southern Victoria on Saturday morning. The outlook for Monday is increasing cloud and strengthening north winds ahead of a change.

GEELONG
Wednesday 11.04.01 Showers developing ahead of a colder south change. Cold night to follow. Strong winds.
Thursday 12.04.01 Showers in the morning then partly cloudy very cool south winds, sunny intervals later.
Friday 13.04.01  Cold morning with Drizzle/fog then fine partly cloudy rather cool. Light winds.
Saturday 14.04.01 Early low cloud fog cold at first then milder with sunny periods and light winds.

Regards Clyve Herbert and Lindsay Smail and the Geelong Weather Services.(NMP)
9 Clyve Herbert SOSE looks interesting tonight especially if you want to see how a cyclone goes puff! The upper cloud shield has all but been blown off leaving a very large apparent eye one of the largest I have seen or at least a near clear central locality.  Also some nice high lee cirrus extending from the eastern North Is of NZ along the east coast of the South Is looks rather spectacular, another area of interest is the remnants of TC Walter getting into the central and southwest of WA, meanwhile Victoria and SA can enjoy the continued spell of anticyclonic control now almost into its 5th year, give or take a few lows.
9 Dave Williams (NSW) I know most people can't imagine that high pressure systems are interesting, but the upcoming one for SE Australia later in the week has the appearances of being one, at least according to the MRF. On Thursday it has very cold temperatures at 850hPa [ie. around 1500 metres] dropping to 3 degrees in Sydney [see averages at end of this note] and -2 ish in the Victorian Alps. Yet at the same time it is going for 1000-500hPa thicknesses of around 5560 and 5520 metres respectively.

The 850hPa = 0 degrees at 5400 metres [this is well known] and varies by 5 degrees for every 100 metres in thickness. So that, for example, a thickness of 5600 metres equates to a 850hPa temperature of +10 etc. Well go back and have a look at the values predicted by the MRF for later in the week. The thicknesses are rather high yet the 850hPa temperatures are very low. On Thursday one would have expected the Sydney thickness of 5560 metres to correspond to a 850hPa temperature of 8 degrees, not the 3 degrees forecast. Whilst for the Victorian ALPS the 5520 would go to +6 degrees, not the -2!

What this is saying is that the cold change that is forecast is (1) very cold and (2) very shallow. Since the thickness represents around 5.5 kilometres of air and the 850hPa temperature refers to around 1.5 km's it is clearly obvious that the model expects the temperatures above 1,500 metres to remain relatively warm. Such a situation is a stable one.

What this means is that (1) the effects of this change are likely to be short-lived and that the airmass will quickly warm up again nearer the surface; (2) that rainfall amounts will in general be fairly light since there will not be any great depth in the cloud due to the 'warm' temperatures aloft and (3) that any location which has sufficient moisture near the surface will experience a 'miserably drab overcast day' because these considerably warmer temperatures will act as a lid and ensure that the cloud doesn't easily burn-off.

One could easily derive some sort of stability index out of these 2 temperatures which could add to the other information available. Considering the Victorian ALPS over the next few days, the forecasts for the 850hPa temp, 1000-500hPa thickness and the 'equivalent 850hPa temp based on the thickess' are:

Tuesday 4 5555 7.75
Wednesday 6 5535 6.75
Thursday -2 5520 6.0
Friday 6 5580 9.0
Saturday 8 5600 10.0

Note how quickly the 850hPa temperature is expected to rise from Thursday to Friday. One needs to be cautious [assuming this model is correct] to quickly rise the maximums along the NSW coast late this week since any location that has moisture underneath this warm air will remain overcast and COLD.

Finally, for those interested, here are the average 850hPa temperatures and 1000-500hPa thicknesses for a few locations at this time of the year:

Sydney 9.4 5588
Wagga Wagga 8.6 5566
Hobart 4.9 5502
Melbourne 7.1 5545
Brisbane 11.5 5643
Adelaide 8.7 5579
Perth 11.0 5619
Alice Springs 14.7 5684
Darwin 17.8 5770
8 Clyve Herbert Sunday 8.04.01. to Wednesday 11.04.01

Hello weather lovers.

AUSTRALIA - AN OVERVIEW

The present phase of anticyclonic control across southern Australia will be temporarily broken this Sunday as a moderate strength mid latitude trough crosses south eastern Australia, strong baroclinic mid and high level cloud development looks impressive over the eastern half of Australia on Saturday but is not producing worthwhile rainfall. The passage of the cold front over Victoria and Tasmania on Sunday should produce showers tending to longer spells of rain moderate in places especially over south-western and mountain areas of Victoria and western/mountain regions of Tasmania, this system however seems to be weakening and there is a possibility that a weak trough may persist over inland NSW on Monday with isolated storms possible. High pressure should then re-establish control across the Australian Bight towards the south east of Australia during Monday and Tuesday. Tropical Cyclone SOSE is also worth keeping a close look at over the next 24 to 48 hours as there is a risk this system may edge towards the QLD mid north coastal areas. A tropical disturbance continues to linger near to the Gulf of Carpentaria and should continue to bring showers/storms to that region over the next several days, another area of interest is decaying TC Walter well west of Broome and extending a strong cloud band towards the WA sub tropical coast this may result in patchy rain affecting that region over the next 24/36 hours. Cold nights should again develop over southern SA and inland Victoria from Sunday through to Wednesday.

VICTORIA.....A complex trough and cold front will move through the state on Sunday with extensive high cloud, showers should affect most regions and tending to longer outbreaks of rain especially in the west and along the ranges some moderate falls are a possibility, strong northeast to northwest winds will change to cooler westerlies on Sunday morning in the west and moving steadily eastward to reach the far east by late Sunday night, the large mid and high level cloud band should then clear eastward with the wind change but showers should continue to affect southern and mountain regions in the unstable westerly flow, showers should then become increasingly isolated on Monday under the influence of a strengthening high pressure ridge extending from the west although another weak cold front may affect coastal areas later Monday. Tuesday should see some drizzle and early morning fog in the south and fine conditions in the north after a cold morning. Wednesday will be mainly fine although some coastal drizzle may occur especially over south Gippsland.

GEELONG outlook...
Sunday 8.04.01
Strong very mild north winds ahead of a cooler west change, showers and the risk of a storm.
Monday 9.04.01
Very cool morning then partly cloudy with a shower or two fresh, west to southwest winds.
Tuesday 10.04.01
Cold morning early fog/drizzle then partly cloudy. Longer sunny spells in the afternoon.
Wednesday 11.04.01
Cold morning with fog/low/cloud. Fine mild and mainly sunny day.


Regards Clyve Herbert and Lindsay Smail and the Geelong Weather Services.(NMP)
7 Anthony Cornelius (QLD) I think the main factor is the shear - a fairly strong STJ is sitting south of Sose (running at 80-90kn, although the shear tendancy is weakening in this area) I thinkt he effects of the STJ can be seen on the sat pics, on its current track it is going to go into increasingly unfavourable shear, which may curb its intensification, however has Simon pointed out, it JTWC are suggesting a more westward movement which could prove interesting - as there is a weakening of the STJ moving through. The BoM are expecting big swells on Monday and Tuesday for the south QLD coast. Fiji insist this system will recurve SE soon though. The waters though can certainly support a monster - it really needs to drift slowly westward to intensify into a significant TC - as southward is not so favourable (although SST's are more than ample). Currently it is 985hPa.
6 Clyve Herbert Very nice baroclinic zone developing over central Australia tonight in response to a developing low south east of Esperance, also a nice cold air field moving into the western Bight region, best of all is the mid and high cloud extending from the tropical disturbance over the Top End of the NT.  At the moment this set up is looking ok for general rain across eastern Australia especially when the cold front mixes in on Saturday.  Keep a watch on Cyclone SOSE which is moving westward - this may develop into a monster and may push to cat 4/5 (what do you think Anthony?) over the next 24 to 36 hours if a westward motion is favoured it may sail close to the eastern side of Australia, although the major trough over the Bight may influence a more south to southeast movement by Sunday
3 Clyve Herbert There are two potential locations for interesting tropical developments tonight, the Gulf of Carpentaria has a persistent region of convergence worth a continued check on there is some outflow over this region too, also a large and persistent region of convection is located north of Fiji this region also shows potential for development over the next 24 hours
1 Clyve Herbert Sunday 1.04.01. to Thursday 5.04.01

Hello weather lovers.

AUSTRALIA - AN OVERVIEW
The phase of anticyclonic control is continuing across southern Australia with the baric ridge extending from just south of Perth to Victoria. The present high pressure phase will persist through to Wednesday and Thursday with the present strong primary centre moving from west of Tasmania on Monday to be located east of Tasmania by Wednesday or Thursday. In tropical areas of the north of Australia, there is a weak return to humid and more active conditions with associated showers and storms mainly over the north of QLD and the Top End of the Northern Territory, also there is an area of weak to moderate convergence over the Gulf of Carpentaria on Sunday, this area is worth keeping a check on over the next two days, although the chance of any development appears to be less than 30%.   For the rest of Australia conditions should remain on the dry and fine side although nights will be rather cold across much of the southern states except WA.   Also overnight and morning fog should become more general across Victoria on Tuesday and Wednesday, coastal showers will affect the east coast mainly north of Batemans Bay.

VICTORIA.....A weak cold front will clear the state on Sunday with isolated showers in the south and along the dividing range, early drizzle and light showers for Monday and Tuesday morning in southern areas but some sunny intervals in the afternoons. Wednesday and Thursday should become fine except for widespread overnight and morning fog areas in southern Victoria, however milder and sunny afternoons should follow. The north of Victoria will become fine and sunny for most of the week but with cold mornings with isolated fog, some light frost should affect alpine areas especially from Monday night.

OUTLOOK FOR GEELONG...
Monday 2.04.01
Early low cloud and drizzle then fine and partly cloudy, cool south wind, sunny intervals by the afternoon.
Tuesday 3.04.01
Early low cloud or fog/drizzle,then fine and partly cloudy, cool to mild southeast wind.
Wednesday 4.04.01
Early morning low cloud/fog then becoming fine and sunny, light winds, mild afternoon.
Thursday 5.04.01
Morning mist and fog then fine and sunny with light winds, mild to warm afternoon.
Trend for Friday and the weekend
A trough and cold frontal system appears to be approaching later Thursday and Friday with the possibility of unsettled conditions and increasing north to northeast winds.  Some patchy rain or showers expected, and the risk of thunderstorms with this weather system.

Regards Clyve Herbert and Lindsay Smail and the Geelong Weather Services.(NMP)
Victorian Weather Glass
27/3/2001 Clyve Herbert AUSTRALIA - AN OVERVIEW
The first stages in the arrival of the Top End dry season are now underway, the large and slow moving high over the Australian Bight is the strongest high pressure system to affect the Australian region for some time. This system has pushed a surge of drier east to south-easterly winds into much of northern Australia and pushed the ITCZ offshore. The arrival of the early stages of the southeast trades will spread drier air into the northern tropics over the next three to five days, with a brief return to more humid air over the tropics after this weekend. The remainder of Australia will be strongly influenced by the high pressure system until the weekend as it migrates slowly towards the Tasman Sea by Saturday.  Following this high pressure phase across southern Australia, a trough and associated cold frontal complex will follow affecting southwest WA from Thursday, and spread eastward to affect the southeast of Australia and Tasmania later this weekend. The passage of this high pressure area will be accompanied by several cold nights over inland parts of southern Australia with early season frosts a risk. The east coast of Australia should see a prolonged spell of showers especially north of Sydney. The remainder of Australia should remain mostly on the dry side.

VICTORIA.....Cool to very cool conditions with light showers and drizzle over southern and mountain regions until at least early Wednesday, dry and mostly sunny conditions in northern Victoria throughout the forecast period until the arrival of a trough and cold front later Saturday or Sunday with patchy rain.  Some cold nights over inland parts of Victoria with the risk of frost especially Thursday and Friday mornings.  More general sunny and warm conditions throughout Victoria later Friday and Saturday.

GEELONG AREA....
Tuesday 27/3
Cool. Partly cloudy with brief sunny intervals and very occasional light showers.
Wednesday 28/3
Partly cloudy with a brief shower or early drizzle - cool to mild sunny periods later.
Thursday 29/3
Some early cloud or drizzle/fog then becoming fine and mild.
Friday 30/3
Early fog or low cloud then mainly fine and mild,
Saturday 31/3
Mainly fine and sunny after a cold morning with fog patches - a warm afternoon.
Sunday 1/4
Increasing high cloud and fresh north winds. Warm but some patchy rain possible later.

Regards Clyve Herbert and Lindsay Smail and the Geelong Weather Services.(NMP)

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