Date: Fri, 18 Sep 1998 07:00:32 +1000
From: Anthony Cornelius 
To: aussie-weather at world.std.com
Subject: Re: aussie-weather: bristorm outlook
Sender: aussie-weather-approval at world.std.com
Reply-To: aussie-weather at world.std.com

Well, this morning on the radio they said possible late storm for
Monday, but BoM's homepage is only saying chance of late shower.

The models show a weak trough over us on Monday, with a slightly thinner
500hPa thickness of approximately 560, the 700 precipitation shows some
to the W of us on Monday morning, jetstream divergence is moderate, with
around 30m/s winds, TT's are around 30.  But the moisture levels in the
850 are quite high (70-80%) which in my experience can sometimes produce
rain over storms...

This is MRF only.. NGP shows the main jetstream to the N of Brisbane,
and does not show the trough in the 500hPa area, and has much less
moisture in the 850 level (50-70%)  But it still shows a band of
precipitations from SE NSW, up to NE QLD and into N of Adelaide, just
like MRF shows it, but not quite as far north.

But +96hr forecasts can still have many fluctuations with them!  We'll
see what happens!

Anthony

James C wrote:

>  The trough which should approach Brisbane early next week is expected
> to weaken unfortunately.  An "afternoon shower" is however forecast
> for Monday and 25C.  Today winds turned more SE'ly after a cold night
> with SW winds.  Many large cu are situated just on and off the coast
> with little rain at this stage.  In the next 2 days a few showers will
> fall, but temps will gradually increase.  Ipswich (near Bris' western
> suburbs) is expecting 26 tomorrow and 28 on Saturday. Well I'm hoping
> that trough doesn't weaken quite as much as expected.  In the next few
> days I'll report again.  If I don't, it'll be because I'm pissed off
> about no storms! JamesBrisbane

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X-Sender: mbath at ozemail.com.au
Date: Fri, 18 Sep 1998 13:23:25
To: aussie-weather at world.std.com
From: Michael Bath 
Subject: aussie-weather: water spouts at Clifton Gardens (sydney)
Sender: aussie-weather-approval at world.std.com
Reply-To: aussie-weather at world.std.com

fyi..

>Date: Wed, 16 Sep 1998 21:45:53 +1000
>From: R 
>To: mbath at ozemail.com.au
>Subject: water spouts at clifton
>
>A water spout damaged the roof of the Imperial Hotel at Clifton around
>the 18th August. A neighbor saw the spouts approaching and ran inside.
>The rafters of the roof were split. Call the Publican Sveti Ignatovic if
>you would like to know more.
>
>Ray Gillis
>
>
>
*=====================================================*
               Australian Severe Weather
     http://australiansevereweather.simplenet.com/
 thunderstorms, tropical cyclones, weather photography
   storm chasing, tornadoes, observations, lightning
*=====================================================*
 
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Date: Fri, 18 Sep 1998 14:56:41 +1000
From: Anthony Cornelius 
To: aussie-weather at world.std.com
Subject: Re: aussie-weather: water spouts at Clifton Gardens (sydney)
Sender: aussie-weather-approval at world.std.com
Reply-To: aussie-weather at world.std.com

Interesting!  But were they really water spouts or tornadoes?  Just that
I didn't think a water spout could survive the transition between water
and land.  I thought only tornadoes could...so therefore wouldn't it be
by definition a "tornadic waterspout?"  Or perhaps I'm wrong...

Anthony

Michael Bath wrote:

> fyi..
>
> >Date: Wed, 16 Sep 1998 21:45:53 +1000
> >From: R 
> >To: mbath at ozemail.com.au
> >Subject: water spouts at clifton
> >
> >A water spout damaged the roof of the Imperial Hotel at Clifton
> around
> >the 18th August. A neighbor saw the spouts approaching and ran
> inside.
> >The rafters of the roof were split. Call the Publican Sveti Ignatovic
> if
> >you would like to know more.
> >
> >Ray Gillis

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Date: Fri, 18 Sep 1998 19:54:38 +1000 (EST)
From: Paul Graham 
To: aussie-weather at world.std.com
Subject: aussie-weather: Info. on Tornadoes...
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Reply-To: aussie-weather at world.std.com


> Interesting!  But were they really water spouts or tornadoes?  Just that
> I didn't think a water spout could survive the transition between water
> and land.  I thought only tornadoes could...so therefore wouldn't it be
> by definition a "tornadic waterspout?"  Or perhaps I'm wrong...

There are no great distinctions.  A tornado over the water is a waterspout
and a waterspout over land is a tornado.  Strong tornadoes/waterspouts
tend to be the result of deep circulations (mesocyclones) associated with
supercell thunderstorms and tend to be a spring or summertime continental
feature.  Weak tornadoes/waterspouts tend to be the result of shallow
circulations (misocyclones) perhaps resulting from a convective cell
outflow boundary or a gust front and are common over land and ocean alike. 
Sometimes the term "tornadic waterspout" is used to refer to a tornado
over the sea which resulted from a deep circulation (mesocyclone).  Again,
there are no strict distinctions since they are all just localised
whirling winds. 
Hope you find what I wrote useful.
- Paul 

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Date: Fri, 18 Sep 1998 20:06:41 +1000 (EST)
From: Paul Graham 
To: aussie-weather at world.std.com
Subject: aussie-weather: April Waterspout...
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A friend of mine informed me recently that he and a friend spotted a
waterspout off Norah Head around Mid-April.  When I see him next I'll see
if I can find out what day it was but I remember that we had quite an
intense storm system on Good Friday so perhaps it was around that time?  -
Paul.