Severe Weather Threat 3/7-3/9/2024

[Justin Hindman Hindy]

Gonna be a rain wrapped isolated tornado kind of day.

 

[South AL Wx]

As for the flooding potential, Moderate Risk issued for parts of AL/GA:

 

[wx_guy]

Looking at the data from last night/this morning, I feel like the tornado threat will be mostly confined to within 100 miles from the coast, mainly beginning around Mobile and further east. The other areas are probably more likely to get damaging hail.

Here's the 0z NAM and 20z on Saturday at Eglin AFB in the FL Panhandle:


The same sounding, but 4 degrees warmer on Temp and Dewpoint:


Both soundings have very curved low-level hodographs, high-ish CAPE for the area, and pretty high Eff Shear. Definitely worth watching.

 

[Clancy]

Looking at the data from last night/this morning, I feel like the tornado threat will be mostly confined to within 100 miles from the coast, mainly beginning around Mobile and further east. The other areas are probably more likely to get damaging hail.

Here's the 0z NAM and 20z on Saturday at Eglin AFB in the FL Panhandle:

View attachment 24133
The same sounding, but 4 degrees warmer on Temp and Dewpoint:
View attachment 24134

Both soundings have very curved low-level hodographs, high-ish CAPE for the area, and pretty high Eff Shear. Definitely worth watching.

Definitely concur on geographical distribution. Wind fields get pretty bleh as you go north, regardless of moisture quality. Kind of surprised by the inland extent of instability being modelled right now, though.

 

[wx_guy]

Definitely concur on geographical distribution. Wind fields get pretty bleh as you go north, regardless of moisture quality. Kind of surprised by the inland extent of instability being modelled right now, though.

Yeah, the 12z NAM 3k is just coming in on Pivotal Weather, and it's showing some unexpectedly high CAPE inland. If the hodographs can fix themselves, central AL and GA may be in the firezone too.

 

[UncleJuJu98]

 

[JPWX]

I could see where the Moderate Risk gets expanded back westward some.

 

[KevinH]

I could see where the Moderate Risk gets expanded back westward some.

Moderate risk for RAINFALL right? RIGHT?! LOL

EDIT: added “LOL” to convey sarcasm ha!

 

[JPWX]

Moderate risk for RAINFALL right? RIGHT?!

Yes Kevin. You can relax

 

[KevinH]

Yes Kevin. You can relax

Hahahahhaa

I haven’t seen anything to warrant a MOD tor risk for tomorrow yet. Not even close.

 

[JPWX]

Hahahahhaa

I haven’t seen anything to warrant a MOD tor risk for tomorrow yet. Not even close.

Me neither. I could see a Enhanced Risk at best but that would be highly dependent upon mesoscale factors.

 

[KevinH]

Me neither. I could see a Enhanced Risk at best but that would be highly dependent upon mesoscale factors.

Yep! That is about where I am too. At least for LA/MS and MAYBE parts of AL. We will see how things evolve.

I think my threat will be late Friday, overnight into Saturday… FOR NOW.

 

[Clancy]

NAM 3km improved wind fields across the northern extent of the OWS, but HRRR heavily disagrees and has overall pretty unidirectional shear. Sounding off the NAM at 18Z Saturday SE of Rome, GA. HRRR has a robust MCS moving through central GA early morning Sat. which seems to dampen things, versus the NAM with less morning convection.

 

[wx_guy]

Yeah, we'll definitely how to see how far north this can go. But where it CAN go, it looks more and more concerning, at least in my (non-professional) eyes. Here's the 18Z HRRR zoomed in on Alabama showing a robust quasi-discrete set of supercells moving through the FL Panhandle and SE AL and SW GA. Sounding is for the southeast corner of AL, just ahead of the supercelluar line. Over 1k+ CAPE, EHI of about 2.5, 61 knots of effective shear, and low-level hodograph hook, as well as both STP's over 2.0 and a 70 degree dew point. Not to mention the > 900 DCAPE and ~7 Lapse Rates and 1.0 SHIP parameter. So not only tornadoes but but damaging winds and hail are a possible concern too. There ARE mitigating factors in my opinion - the wind fields and hodographs are still not off-the-charts for rotation, so it may be difficult for the storms to take advantage of the conditions to produce tornadoes, and earlier MCS structure and pop-up storms may put a lid on things some...AND it's still long-range for the HRRR, which tends to do better in the 12-24 hour range than 40+ hours out. So I'm not sold on it yet, but if this pans out like this, it'll definitely be noteworthy. For now, 100-150 miles from the coast still seems most supportive, but as mentioned earlier, that could change.

 

[atrainguy]

 

[Clancy]

Maaaan, chasers are really drooling over these storms in Kansas. Guess they're really stir-crazy.

 

[wx_guy]

Here's the 0z HRRR at 11 AM EST on Saturday. A corridor from Dothan to Macon to Valdosta to Tallahassee shows very conducive soundings for severe weather, with 2k-3k+ CAPE. Curious. Let's see what the other CAMs show.

 

[Clancy]

Here's the 0z HRRR at 11 AM EST on Saturday. A corridor from Dothan to Macon to Valdosta to Tallahassee shows very conducive soundings for severe weather, with 2k-3k+ CAPE. Curious. Let's see what the other CAMs show.


View attachment 24142

NAM came in less aggressive than its 18Z run (due to more comprehensive depiction of the morning MCS), but still is more keen on the North-Central GA corridor than the HRRR. Wind fields seem to have become a little better this run as well (sounding from Paulding Co., GA). Still skeptical anything actually develops here, but if it did then it could be troublesome. SREF sniffs some geographically-confined risk for tornadoes near the ATL metro, but seems like a low-confidence scenario. Either way, rain will be tremendous across parts of AL/GA so folks should really watch out for that. Watch your roofs and garage doors for leaks everyone!

 

[keithGA]

@KevinH got the boat ready?

 

[KevinH]

@KevinH got the boat ready?

Nope… lol

That number 5 is right over me too *sigh*