Severe Weather Threat - January 8th-9th, 2024

[KevinH]

FWIW, CIPS-forecasted SHERB values via the GFS have been consistently robust over MS/AL/GA. While more classic parameters aren't showing very much over the area of interest, I still think the northward edge of the threat bears very close watching. A pretty minor difference in the amount of moisture and available energy could translate to a serious difference in the performance deeper inland, considering the wind fields at hand (sounding from East-Central AL).
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Interesting. Never heard of SHERB before. Something to look into.

 

[JBishopwx]

So as far as areas impacted by next Tuesday, do we think it'll be farther north than the Gulf Coast? Personally, I still believe it'll be further north than models currently have it.

Jackson has pulled their risk area north.

 

[Clancy]

18Z GFS coming in about the same.

 

[JBishopwx]

All of the local WFOs are also mentioning the non-thunderstorm wind threat also. Could easily see 45-50mph gusts outside of thunderstorms Monday evening and Tuesday.

 

[Clancy]

A couple very non-authoritative, passing observations from a generic hobbyist regarding failure modes, warm sector potential and implications.

1) A moisture wedge and/or rain shield situation seems to one of the biggest potential threat mitigators for the northern halves of MS/AL/GA.
2) Dixie tornadoes are known for often getting gnarly while riding moisture boundaries, which could be an issue depending on where the northern edge of the WS sets up.
3) Coastal crapvection could cut off northward expansion of the warm sector, and though I don't see this clearly modelled, that certainly doesn't rule it out.
4) Currently, the trends in models seem like they suggest a fast-moving QLCS from the 7th Circle.
5) If the models slow the system down like they often do, might allow for more discrete development, but who knows.



Overall conclusion? I dunno *shrugs* but there's a lot of factors to juggle here, and a lot of things that could go any which way between now and next week.

 

[JPWX]

A couple very non-authoritative, passing observations from a generic hobbyist regarding failure modes, warm sector potential and implications.

1) A moisture wedge and/or rain shield situation seems to one of the biggest potential threat mitigators for the northern halves of MS/AL/GA.
2) Dixie tornadoes are known for often getting gnarly while riding moisture boundaries, which could be an issue depending on where the northern edge of the WS sets up.
3) Coastal crapvection could cut off northward expansion of the warm sector, and though I don't see this clearly modelled, that certainly doesn't rule it out.
4) Currently, the trends in models seem like they suggest a fast-moving QLCS from the 7th Circle.
5) If the models slow the system down like they often do, might allow for more discrete development, but who knows.

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Overall conclusion? I dunno *shrugs* but there's a lot of factors to juggle here, and a lot of things that could go any which way between now and next week.

Primary Threat outside of tornado potential especially with that squall line is gonna be widespread damaging winds in addition to the non-thunderstorm winds.

 

[JPWX]

Also these storms are gonna be booking it so there may not be that much lead time. Hopefully there is though.

 

[Clancy]

Also these storms are gonna be booking it so there may not be that much lead time. Hopefully there is though.

Yeah, whether discrete, mixed or squall, they'll be hauling like a freight train.

 

[Taylor Campbell]

I'm curious to see how this event ends compared to the Jan 24-25th event from last year.

 

[JBishopwx]

Monday:


Tuesday:

 

[KevinH]

Monday:
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Tuesday:
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Whoa

 

[Clancy]

CSU probs for mid-range.

 

[Taylor Campbell]

 Last night’s operational Canadian and EURO were not impressed with the chances of substantial moisture advection inland into southern Alabama like the GFS. I remember they both performed better than the GFS with that regard to last year’s Jan 24-25th event.

 

[KevinH]

 Last night’s operational Canadian and EURO were not impressed with the chances of substantial moisture advection inland into southern Alabama like the GFS. I remember they both performed better than the GFS with that regard to last year’s Jan 24-25th event.

I keep seeing others say that models generally don’t handle moisture return in the winter very well.

Something to keep in mind and watch out for.

 

[Clancy]

 Last night’s operational Canadian and EURO were not impressed with the chances of substantial moisture advection inland into southern Alabama like the GFS. I remember they both performed better than the GFS with that regard to last year’s Jan 24-25th event.

EURO is depicting persistent coastal convection which is probably going to keep energy and moisture from moving northward if it verifies.

 

[UncleJuJu98]

EURO is depicting persistent coastal convection which is probably going to keep energy and moisture from moving northward if it verifies.
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Maybe the saving grace of this system

 

[KevinH]

EURO is depicting persistent coastal convection which is probably going to keep energy and moisture from moving northward if it verifies.
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These pics still have an ugly look to them lol

 

[Clancy]

These pics still have an ugly look to them lol

Indeed, but the coastal convection could take a serious bite out of any threat to the north.

 

[KevinH]

Indeed, but the coastal convection could take a serious bite out of any threat to the north.

True. That seems like it has the potential to be a hiccup… frequently lol

Should be interesting to see how all of this plays out.

 

[UncleJuJu98]

Indeed, but the coastal convection could take a serious bite out of any threat to the north.

Watch the mesoscale models come in and say, "that's not issue" lol