Page 1 of 12 1 2 3 ... 11 12 >
Topic Options
#1439462 - 28/10/2017 13:20 SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017
Ken Kato Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 4683
On current indications, Sunday looks good for just inland of the coast with the chance of some reaching the coast...... while Monday looks a lot more coastal (could even be an all-or-nothing setup due to the dryline being close to the coast as the W'lies break through albeit with a seabreeze trying to push into the coastal fringe).

Here's some of my observations based on latest model runs:

SUNDAY:
* Some differences in morning solar heating between EC and ACCESS-R... the former confines any patchy cloud to northern SE QLD while the latter has a fair bit of cloud early morning (also has some patchy precip in the south) before contracting it to northern SE QLD during the morning.
* GFS is more aggressive than the others with pushing the afternoon seabreeze front in further inland.
* BIG difference in late afternoon coastal capping between GFS and ACC-R. GFS has a big cap (partly due to a stronger seabreeze) while ACC-R hardly has any (but both have weaker capping early afternoon).
* Reasonable WSW'ly steering winds aloft (for any non-severe activity).
* Reasonably good shear.
* Somewhat high-based storms again although a few may try to develop lower bases if they manage to get into moister air near the coast.
* If any manage to become severe, main threat looks like being damaging winds again with an outside chance of large hail.
* Multi-model consensus has highest probability of precip just inland of the coast but still reasonable values along the coast... but just short sharp rainfall rather than any huge amounts.
* Hotter than normal.

MONDAY:
* Reasonably consensus re morning cloud cover between ACC-R and EC (both currently suggest patchy cloud in northern/northwestern SE QLD before clearing).
But this depends on not much overnight showers/storms activity.
* Good consensus for the W'lies almost breaking through to the coast by the afternoon.
* Good consensus for the S'ly coastal change reaching the central SE QLD coast early Tuesday morning (yes, as per usual).
* Good consensus for the lower levels drying out a lot later in the day & producing inverted-V soundings
* Good consensus of a sharp dryline close to the coast due to the dry westerlies breaking through almost to the coast (but EC/ACC-R still
* Reasonable WSW steering winds aloft.
* If any storms end up managing to form, they could be pretty photogenic with big crisp white billowing structures which are characteristic of these setups.
* Main threat looks like damaging winds.
* Multi-model consensus has so-so probabilities of precip close to the coast (slightly higher around the Sunshine Coast).
* Not putting too much weight on GFS precip forecasts since it's got a known habit of producing spurious precip forecasts (latest example was Thursday's storms when it was consistently putting a big blob of precip over northern SE QLD when the opposite actually ended up happening).
* Even hotter than Sunday with max temps reaching the mid 30's.

So basically, most things look alright for Sunday, although if the cap is stronger than expected, it could make it harder for storms to reach the coastline (but this isn't currently supported by ACC-R).

And Monday looks like being one of those classic "will there be enough moisture in time for near-coastal storms?" type dryline setups. If there is, photogenic storms will probably form close to the coast. If there isn't and thigs dry out too much, storm chances will be much lower or be far more localised.

1st and 2nd images below - percentages of the models via OCF that are dropping any rainfall between 9am Sun and 9am Mon... and 9am Mon and 9am Tue respectively:

3rd image - outflows from the Sunday afternoon's convection in EC (but these are visible all the time in EC and other high resolution models whenever there's decent convection). I don't really treat their positioning too literally but when you see a lot of big clearly defined ones around, they can be a useful indicator of reasonable thunderstorm risk:








Edited by Seabreeze (29/10/2017 14:55)
Edit Reason: replaced 'possibly' with 'potentially' so it has a different title to the most recent one

Top
#1439484 - 28/10/2017 16:14 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Mad Elf #1.5 Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 2904
Loc: Mt Hallen QLD
Thank you for taking time to put up all the info Ken, very much appreciated. Hope tomorrow has more profit than that last one but happy we missed out on the bashing some got, cheers.

Top
#1439485 - 28/10/2017 16:17 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Ken Kato Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 4683
No worries Mad Elf.

Regarding Monday, if EC is right (and that's far from certain at the moment), there'll probably be REALLY photogenic crisp-looking nuke build-ups near the coast which happen so often with these near-coastal drylines.

But there could just as easily be little to no storms if the dry westerlies break through too early.

Top
#1439486 - 28/10/2017 16:21 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Mad Elf #1.5 Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 2904
Loc: Mt Hallen QLD
I'll gladly take what I get, thanks. Havagoodweekend.

Top
#1439488 - 28/10/2017 16:36 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Mega Offline
Meteorological Motor Mouth

Registered: 03/02/2003
Posts: 6623
Loc: Maryborough, Wide Bay, QLD
I think Monday is stuffed now, GFS & ACCESS-R both bring the dryline onto the coast by the afternoon. Even if it does sit a little inland, given the big cap along the coast you usually need something to fire off inland, which is usually impossible in these setups as dry air mixes down through the lower levels. Northern WBB & Capricornia look much better.

Top
#1439490 - 28/10/2017 16:48 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
PlumbBob Offline
Weather Freak

Registered: 07/05/2011
Posts: 512
Loc: Ashmore Gold Coast
Top Value as always Ken cool

We're having a family arvo on Paradise Point Tomoz, more cameras than food, Lol. Tho even some structure during sunset be good, anything else a bonus when being put.

Moisture looks to move further inland later arvo/eve - if nothing starts around or Wst of the GC during day/arvo, then maybe an off-shore light show cool

Rgrds ...
_________________________
Weather or not ?

Top
#1439492 - 28/10/2017 17:00 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Lani Offline
Weatherzone Addict

Registered: 29/01/2011
Posts: 1059
Loc: Jimbour, QLD
TWO huntsman on my doorstep yesterday, EWWWWW! So is that because we've had rain, or because we're getting more? Let's see what happens. Remember, so far in 5 years, two or more huntsman in my house (that's counts my doorstep lol) means rain within a week or less. So far hasn't missed a beat. Better than the ants LOL. When we see a couple of the hairy ground spiders heading inside I KNOW we're getting rain. PS: I HATE spiders. Sigh.


Edited by Lani (28/10/2017 17:01)
_________________________
Jimbour rain: 2017-483.5, Jan-103.5, Feb-67.5, Mar-118.5, April-0, May-7, June-21.5, July 33.5, Aug-2.5, September-1, Oct-112, Nov-21

2016 - 563.5
2015 - 702.5
2014 - 418.5

Top
#1439494 - 28/10/2017 17:05 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
gleno71 Offline
Weatherzone Addict

Registered: 09/11/2007
Posts: 1293
Loc: Australia
Why is the cap such a issue on the coastal area's compared to inland? Had this always been the case over the years? I don't recall people here talking about the cap in the early days of this forum, unless my old age is catching up on me.

Top
#1439495 - 28/10/2017 17:08 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: gleno71]
Ken Kato Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 4683
Originally Posted By: gleno71
Why is the cap such a issue on the coastal area's compared to inland? Had this always been the case over the years? I don't recall people here talking about the cap in the early days of this forum, unless my old age is catching up on me.

That's always been the case when the cooler shallow layer of air with afternoon seabreezes comes in over the coast and undercuts the (relatively) warm air directly above it.
Doesn't happen all the time though.

Top
#1439496 - 28/10/2017 17:11 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Mega]
Ken Kato Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 4683
Originally Posted By: Mega
I think Monday is stuffed now, GFS & ACCESS-R both bring the dryline onto the coast by the afternoon. Even if it does sit a little inland, given the big cap along the coast you usually need something to fire off inland, which is usually impossible in these setups as dry air mixes down through the lower levels. Northern WBB & Capricornia look much better.

Data from latest (00z) EC is coming in and it's still insisting on the W'lies not breaking completely through to the coast, and therefore allows a northerly stream with dewpoints close to 20C over the coast.

Will be interesting to see what happens but could really go either way.

Top
#1439499 - 28/10/2017 17:19 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
paulcirrus Offline
Weatherzone Addict

Registered: 08/08/2011
Posts: 1455
Loc: Brisbane - Windsor
Thanks Kenn. I reckon there will be too much high cloud around tomorrow for anything to develop.
_________________________
If it's Flooded - FORGET IT

Top
#1439500 - 28/10/2017 17:46 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: paulcirrus]
Ken Kato Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 4683
Originally Posted By: paulcirrus
Thanks Kenn. I reckon there will be too much high cloud around tomorrow for anything to develop.

The band does look impressive on satpics but a number of models suggest most of it might clear out later in the morning (which would be great if it happened).

Always very hard to know what'll happen one day out only based on realtime conditions since things can change quickly in a non-linear way and current conditions may not be representative of the forecast time. Even several hours out is hard.

Top
#1439501 - 28/10/2017 17:47 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
jessie Offline
Weather Freak

Registered: 14/10/2011
Posts: 82
Loc: Mt forbes
35 degrees tomorrow west of Ipswich, shouldn't that spark something. Getting a feel for a storm ,muggy and no seabreeze here today

Top
#1439502 - 28/10/2017 18:00 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Mega Offline
Meteorological Motor Mouth

Registered: 03/02/2003
Posts: 6623
Loc: Maryborough, Wide Bay, QLD
Originally Posted By: Ken Kato
Originally Posted By: Mega
I think Monday is stuffed now, GFS & ACCESS-R both bring the dryline onto the coast by the afternoon. Even if it does sit a little inland, given the big cap along the coast you usually need something to fire off inland, which is usually impossible in these setups as dry air mixes down through the lower levels. Northern WBB & Capricornia look much better.

Data from latest (00z) EC is coming in and it's still insisting on the W'lies not breaking completely through to the coast, and therefore allows a northerly stream with dewpoints close to 20C over the coast.

Will be interesting to see what happens but could really go either way.


Just looking at this now on Layers. Very solid, and surprising to say the least. Development seems to start over southern parts of SEQ during the early afternoon then contract NE as the afternoon progresses. EC has had a knack of getting it right so far this season, hope this time is no different.

Top
#1439509 - 28/10/2017 20:16 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
TWEEDSTORM Offline
Weather Freak

Registered: 08/01/2012
Posts: 616
Loc: Tweed Heads NSW
Dont ya love the dynamics of the atmosphere! So much interesting discussion just regarding the weather thats about to unfold over the next 2 days.This is a great forum thank you guys.

Top
#1439517 - 28/10/2017 21:57 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: paulcirrus]
gleno71 Offline
Weatherzone Addict

Registered: 09/11/2007
Posts: 1293
Loc: Australia
Originally Posted By: paulcirrus
Thanks Kenn. I reckon there will be too much high cloud around tomorrow for anything to develop.


Models at the moment have the high cloud clearing Mid to Late morning, possibly lunch, further inland it will clear earlier.

A wait and see game

Top
#1439518 - 28/10/2017 21:58 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Mad Elf #1.5 Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 2904
Loc: Mt Hallen QLD
Dont know about anyone else but since all this wetness out here, them scotch greys are out in numbers & attack in swarms without warning.


Edited by Mad Elf #1.5 (28/10/2017 21:58)

Top
#1439519 - 28/10/2017 22:08 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Mad Elf #1.5]
Bone Dry Offline
Weather Freak

Registered: 30/01/2017
Posts: 81
Loc: Wolvi
Yeah, they're bloody brutal at the moment.
_________________________
Guaranteed weather forecast for tonight: Dark.

Top
#1439529 - 29/10/2017 06:16 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
paulcirrus Offline
Weatherzone Addict

Registered: 08/08/2011
Posts: 1455
Loc: Brisbane - Windsor
why am i up soooo early - dam it. Maybe the 2 G and T's I had last night smile But high cloud looks to be clearing by about 8 or 9 am. yipeee smile
_________________________
If it's Flooded - FORGET IT

Top
#1439531 - 29/10/2017 06:23 Re: SEQLD/NENSW - Thunderstorms, some potentially severe - 29th/30th Oct 2017 [Re: Ken Kato]
Ken Kato Offline
Weatherzone Addict

Registered: 05/03/2012
Posts: 4683
Yeah, great sight to see (so far).

Top
Page 1 of 12 1 2 3 ... 11 12 >


Who's Online
14 registered (Perfect Storm, Sidney, Winter_lover, Snowies, ThunderBob, Cheers, Kino, Mick O'Halloran, Homer, Steve777, Foehn Correspondent, duckweather, 2 invisible), 346 Guests and 2 Spiders online.
Key: Admin, Global Mod, Mod
Today's Birthdays
avalon, philiphart, Ravenous2411, Sasho
Forum Stats
29421 Members
32 Forums
23735 Topics
1469485 Posts

Max Online: 2925 @ 02/02/2011 22:23
Satellite Image