Storm SEQLD/NENSW Scattered Thunderstorms - Nov 29th to Dec 1st 2019

[Seabreezes]

5.0mm from a thunderstorm that rumbled through here a bit earlier this afternoon.

The isolated storm activity that moved through the north coast this afternoon has pretty much cleared the coast now. Strong storms are currently moving onto the northern slopes.
Latest STW map:

Edit: This is the bluest sky here since early November. I've gotten used to having reduced visibility from the smoke, so this feels a bit weird, haha.

 

[Lani]

No worries, just remember though, I'd avoid using Total Totals by itself because it uses lapse rates in conjunction with low level moisture in its formula i.e. (850hpa temp - 500hpa temp) + (850hpa dewpoint - 500hpa temp) and lapse rates are typically a lot lower in the tropics and a lot higher in the midlatitudes... they also vary with time of year.

For our particular region, look for areas where TT values exceed about 45 and ideally greater than 50, overlapping with surface based CAPE of at least a few hundred j/kg or more. Those areas tend to correlate fairly well with thunderstorm initiation. If steering winds aloft are strong, any storms that form in those areas can be advected into areas with less favourable values.
That's if you're short on time. It's better to look at soundings as well to get a more accurate picture as well as taking into account what's happened in the past with the same kind of setup.

There's other people on here who I think are really knowledgeable with weather and realistic with what's likely to happen, and who you could ask as well e.g. Mega, but there are others as well.

You can see from the latest multimodel accumulating precip graph for Brisbane that all the models on there are currently going for at least some rainfall for Brisbane which is encouraging... for now at least anyway.

Hey Ken, Is there a link I can run this for, for Jimbour or Dalby.

 

[Ken Kato]

Hey Ken, Is there a link I can run this for, for Jimbour or Dalby.

Yep, this example's for Dalby: https://weather.us/forecast/2169535-dalby/xl/euro/precipitation-total

But when it comes to showers or thunderstorms, I'd avoid treating those amounts too literally since one person can get high totals while someone just down the road might get very little.

 

[Gleno71]

Just looking at the Access C model for tonight and sunday. It has some activity reaching the coast later tonight, however I am unsure whether it's on the form of storms or some light precipitation. Those storms way out west now no doubt will be responsible for the cloud cover for Sunday morning which is a major concern for me.

For Sunday, Access C Has the activity starting east of the downs progressing eastwards reaching the coast mid to late afternoon. It looks like a NW to SE line moving thru with the rain/storms not reaching the Sunshine Coast until very late into the afternoon or even after sunset, followed by some weaker activity very late in the evening . So we may even get 2 rounds of storms. That's my take on it, be interesting to see what the next model runs dish up before it's all live and upon us.

 

[Ken Kato]

Yep activity reaching southern and western parts of SE QLD (and perhaps more) tonight def a possibility but especially overnight Sunday night into the wee small hours of Monday morning in some sections of our region, in addition to any activity earlier that evening or daytime (although the chances of this overnight/early morning activity might be reduced if too much widespread earlier activity stabilises the atmosphere more than expected).

A bit of activity now skirting along the southwestern parts of the SEC district as I type this.

 

[PlumbBob]

Thanx a great deal, Tsunami, wow, I had no idea until now, been checking charts in morning, then again in the afternoon, had no idea they'd changed, quite funny actually yet quite a game-changer in reality, the PlumbBob has been recalibrated Whooo ,,,
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Cheers also NF, that's magic stuff Re Times etc
Keool Links too, liking the Tropical Tidbits , speshly the forward-back model-run feature, Ive heard reference to it in posts here & ex WZ, and thought, how do you guys know, must have a photographic memory for the last 3 days, Lol ...
Very much appreciated...
--------------------

Cheers all !!

 

[TweedStorm]

A wealth of information on storm initiation to absorb in this thread, cheers guys. Storm activity skirting to the south of here at present, whether we get something later remains to be seen but that cool strong seabreeze is a pest. Almost feels dry and won't let up. Not helping matters.

 

[Nic Bri]

Great to see some colour bubbling away on the radar, regardless of if it makes the coast. At least some places out west are getting a bit of a sprinkle

 

[Sandbank]

If I am not mistaken, it's raining in Stanthorpe. Thank goodness. Looks like a decent drop as well.
.
Edging it's way toward Warwick. Crossing all available digits.

 

[TweedStorm]

Yeah that second line looks like it's gunna deliver the goods out there and on the coast Let's Hope

 

[Slovenski]

Gentle rain!
Fantastic.
And lightning with thunder. Awww.
A BBQ, perfect rain magnet.
Not complaining,
CHEEEERS

 

[Gleno71]

Beast of a storm approaching Kyogle . Shame I'm at a friends house having dinner otherwise I would be down there . That storm could end up between Byron and Murwillumbah if it maintains strength. If these storms are developing into the night , I hate to think what tomorrow will bring

 

[DDstorm]

Yes. We have light rain, if you can call it that, plus a flang or 2 with rumbles. Yeah baby.

 

[Gleno71]

 

[4107]

A few sprinkles of rain falling here currently at Salisbury, it won't be enough to register in the guage and won't even settle the dust where our grass used to be, but geez it's nice to smell the rain again for a change.

 

[Nic Bri]

Raining here currently, two rumbles heard earlier a palpable reduction of air temp also.

 

[TrentG]

Thunder at 4053. No rain as yet, but just nice to hear that sound. Hopefully promising signs for tomorrow. Note a second line still near Toowoomba... maybe a sprinkle later tonight in the meantime?

 

[Seabreezes]

Quite a lightning active storm moving through here this evening. High-based storm, so it didn't drop much rain. 7.6mm since 9am. A couple of lightning pics I took on my mobile phone:

<<< (damn shutter, lol)

Tomorrow's storm chances for the local area have improved a bit compared to a couple days ago, though I don't expect storms will be as strong as further north.

 

[Taipan]

Quite a lightning active storm moving through here this evening. High-based storm, so it didn't drop much rain. 7.6mm since 9am. A couple of lightning pics I took on my mobile phone:

<<< (damn shutter, lol)

Tomorrow's storm chances for the local area have improved a bit compared to a couple days ago, though I don't expect storms will be as strong as further north.

Yes - you got the better end.

I chased the wrong storm. Woologoolga. Southern one down your way had more action.

See what tomorrow night delivers

 

[Mega]

Quite a lightning active storm moving through here this evening. High-based storm, so it didn't drop much rain. 7.6mm since 9am. A couple of lightning pics I took on my mobile phone:

<<< (damn shutter, lol)

Tomorrow's storm chances for the local area have improved a bit compared to a couple days ago, though I don't expect storms will be as strong as further north.

Damn man, you're having a ripper of a season, though I get the feeling from reading your posts that most of your storms this season have been high-based/low precip stuff with maybe the odd lower based storm mixed in?

 

[TweedStorm]

We've had a stormy evening here too around the Tweed area nothing severe but nice lightning show and gentle rain. 2 nights in a row we can't complain.

 

[Taipan]

Thinking of heading towards Port Macquarie tomorrow night. Action looks to be further south.

Will watch the day develop.

 

[Seabreezes]

Damn man, you're having a ripper of a season, though I get the feeling from reading your posts that most of your storms this season have been high-based/low precip stuff with maybe the odd lower based storm mixed in?

I've just checked, and it's been basically a 50:50 split between high-based and lower-based storms here so far this season.

Yes - you got the better end.

I chased the wrong storm. Woologoolga. Southern one down your way had more action.

See what tomorrow night delivers

Yeah it's now nearly 250kms offshore and it's still producing plenty on the lightning tracker.

 

[Falling_Droplet]

A hot day today with a maximum temperature of 35.2 C. A few drops of rain earlier this evening from a decaying mild thunderstorm. The temperature was a little variable from the mid morning to mid afternoon . Dew point have remained near average and been stable today except for a small rise in dew point just before midday coinciding with the maximum temperature. Relative humidity became moderately low during the day with the minimum reached just before midday also. Light NW to NW winds became ENE to NNE from mid morning with some ESE to NE winds and E to NE from late morning. Tonight the wind became E to NNE with some variable winds also, shifting S to SW from 9pm.

Last 24 hours:

 

[Stormwalker]

Thunder at 4053. No rain as yet, but just nice to hear that sound. Hopefully promising signs for tomorrow. Note a second line still near Toowoomba... maybe a sprinkle later tonight in the meantime?

I heard the thunder too in 4053 - then watched it disintegrate on the radar. I think we had 10-15 drops across the yard.

 

[Flowin]

There’s a bit of a shift between Access C 12z pic1 and 18z pic2 below.
Totals to 10pm.
I would love to see an ensemble version of Access C some day.

 

[Big T]

Gday skier’s And former weatherzoners. First post in here, really crossing fingers we get some action this arvo. Been quite a lean season indeed.

 

[Gleno71]

Welcome @Big T good to see you back

 

[Slovenski]

Gday skier’s And former weatherzoners. First post in here, really crossing fingers we get some action this arvo. Been quite a lean season indeed.

Welcome BigT, great to have you join us.
Cheers

 

[Gleno71]

This morning's cloud cover a concern, hopefully it breaks up a little, looks like some clearance in the scenic rim region.
Just waiting for the FB weather pages to give there opinion, especially Anthony Cornelius to give there opinions on todays setup, and Ken of course. Also BOM QLD twitter feed usually they produce a thunderstorm map on day's like this.

 

[Chilled]

Yep will be waiting eagerly for the observed sounding, despite the cloud I'm interested in the wind profile and the lapse rates for today. Only downside apart from some cooler temps was the winds being straight line through height but still a squall line would still be nice.

 

[Gleno71]

 

[Ken Kato]

Sorry @Gleno71 I haven't had much of a chance to check the latest this morning since I'm packing for a trip to Melbourne to catch the delicious wet coldness there (mid teens there with showers and small hail tomorrow vs mid 30's here) but there's a few things I would add.

Firstly, morning cloud cover isn't always a be-all and end-all, and it only takes a few clearer areas within the cloudband to last a few hours for storms to erupt if the airmass is unstable enough already (and some severe if there's enough shear) or if there's enough forcing upstairs. Of course if there's a lot of it and it lasts more than a few hours, it'll limit storm extent and severity. And sometimes would-be convection embedded too far behind the leading edge of an advancing big thick cloudband doesn't get a chance to develop fully into storms.

Secondly, while the observed sounding is great for the next few hours, I'd caution against relying on it beyond that timeframe because atmospheric profiles can and often do quickly change e.g. a morning 00z sounding here will often show a substantial cap due to the lower atmosphere not having mixed well yet but the cap often weakens by early afternoon (and sometimes disappears for inland areas in the afternoon away from the seabreeze influence)... this often shows up in any non-routine afternoon observed sounding done in a significant pre-storm environment.

Thirdly, any storms today should be pretty fast-moving from the WNW or NW (except for any severe cells) due to the strong steering winds aloft.
These strong steering winds should also help advect any inland storms right through to some parts of the coast and of course the shear means if any storms become vigorous enough, they could easily become severe especially if they develop lower bases. Obviously this depends on exactly how much effect this morning's cloud cover has.
Also if you look at the 1-hourly precip fields in ACCESS-C, you can clearly see how long the streaks of precip are that the showers/storms leave behind which is testament to how quick they'll be moving.

Fourthly, I'd keep a lazy eye out for any possibility of isolated cells developing (or re-intensifying) in-situ near the coast... in addition to any coming from further inland.

Lastly, I note various models including ACCESS-C are still suggesting the possibility of further activity continuing to come through some parts overnight tonight into the wee small hours of Monday morning.
I think this is certainly a possibility given that the upper trough and cold air aloft isn't due to completely clear the area until early Monday morning... so the window of opportunity for further activity won't completely close until then.
In saying that, the overnight activity would depend on any early activity not being excessively widespread and stabilising the atmosphere too much.

 

[Tsunami]

Well. Here in bayside the sun is out. Very humid and hot

 

[Tsunami]

Bsch showing some storm activity for us later but its not overly excited.

 

[Gleno71]

Appreciate it Ken, enjoy Melbourne. I lived there as a kid (Vermont South ) a long time ago but I still remember the weather well .

 

[Tsunami]

28.4c here with 69% humidity. Id say thats a fair bit of moisture in the air
Clouds on radar racing in from west at a hell of a speed

 

[PlumbBob]

Sheeze I envy the Coffs/Port Mac area !
--------------------------------
Plenty of sunshine on the Goldy, temp upto 32* currently, a little excited for today.
A few sprinkles 'ere last night, couple of distant thunders heard, was noice !

Couple o pics, just because, yesty arv of the cell below Boonah heading Easterly that Ken mentioned, a fair way from here at time but created some ok Crepsies ahead of it.
And the clear skies hear at moment, rough stitch.

Looking forward to this arv/eve and over-night - even if collect a few mm,,,

 

[Warlock_01]

First humid day for months. Not sure where they get this 'feels like' temperature from. Feels like 30 not 22 on the gold coast

 

[Ken Kato]

First humid day for months. Not sure where they get this 'feels like' temperature from. Feels like 30 not 22 on the gold coast

If you’re referring to the Apparent Temperature figure on the Bureau’s website, the formula used is very sensitive to the wind speed at the time. As soon as the wind increases or dies away, the AT changes a lot.
For info about what variables are used apart from just wind: http://www.bom.gov.au/info/thermal_stress/

 

[Gleno71]

Cloud really starting to thicken up now out west, close to 100% cloud coverage looking at the Warwick webcam, something needs to happen soon . The Only storms are 300-400km off the coast at the moment

 

[Warlock_01]

If you’re referring to the Apparent Temperature figure on the Bureau’s website, the formula used is very sensitive to the wind speed at the time. As soon as the wind increases or dies away, the AT changes a lot.
For info about what variables are used apart from just wind: http://www.bom.gov.au/info/thermal_stress/

Thanks Ken, that link is a wealth of information. I do have a rough idea what it means, though that was in-depth . We live in the hinterland and there isn't a weather reader/station out here so that's what I was referring to how warm it is out here compared to being on the edge of the seaway

 

[Nature's Fury]

We're still definitely on track to have widespread storms across SEQ, but I've become more pessimistic about Brisbane's chances of severe storms over the last 24 hours. I think our only window is mid-afternoon before we get wider rain areas overnight.

The cloud cover is having a negative affect inland: Warwick is 29/13 (temp, dewpoint), Toowoomba is 28/12. But toward the coastal plains and Sunshine Coast it's a lot better where there is still some sun occasionally shining through: Archerfield is 32/20, Gympie is 32/17 and Gatton is 34/17. The seabreeze is quite strong along the coast and keeping temps down to mid to high 20s.

I'd prefer to be Sunshine and Gold Coast hinterland today, but even then it still doesn't feel or look like a severe storm day.

 

[Gleno71]

What I don't get is why is there so much cloud cover under a northerly / NW flow ? Normally winds from that direction produce clear skies? Anyhow small cell just south of Coffs Harbour. It seems the cells down that way are developing right on the coastline

 

[Nature's Fury]

What I don't get is why is there so much cloud cover under a northerly / NW flow ? Normally winds from that direction produce clear skies? Anyhow small cell just south of Coffs Harbour. It seems the cells down that way are developing right on the coastline

The N/NWlies are only at the surface to 950 level. A lot of the cloud is mid and high level associated with the approaching trough (that you can see on the satellite). Impressive trough though - it stretches from NT to NZ.

 

[TweedStorm]

Yeah certainly doesn't feel like a storm day to me either let alone a severe storm day. Lot of cruddy cloud and strong cool seabreeze along the coast doing its best to hamper things. Anyway we'll just have to wait and see

 

[Ken Kato]

What I don't get is why is there so much cloud cover under a northerly / NW flow ? Normally winds from that direction produce clear skies? Anyhow small cell just south of Coffs Harbour. It seems the cells down that way are developing right on the coastline

Always look at the midlevels rather than just the surface. The surface trough leans back to the west with height as NF touched on.
There's some convection starting to pop up at time of writing this.
I don't like to go by whether it feels like a storm day or not. There's been countless times when that's been said, only for storms to fire up later on. And vice versa where people have said it felt like a storm day but too much capping prevented any storms from happening. Always better to look at the meteorological aspects of it.

 

[Gleno71]

Thanks @Ken Kato and @Nature's Fury .yes can see some clouds forming now north of the Gold Coast

 

[Nature's Fury]

First major cells developing over the ranges west of the dams. Current track looks to be over the western suburbs/Ipswich, but if it strengthens it could push out more toward Brisbane and the bayside itself.

 

[Gleno71]

Latest Sounding, that grey line (TAPP) I think its called shows unstable air from the 700hpa level if i'm not mistaken with some marginal capping . Please correct me if im wrong