Severe weather Feb 10-13th

[UncleJuJu98]

Severe threat will materialize from the southern great plains all the way to the east coast, threats currently TBD.

 

[KevinH]

 

[UncleJuJu98]

Serious weather question? With a trough is positive tilt does that mean there's less significant forcing as well? I think it does but not 100%

 

[UncleJuJu98]

12z Nam looks like it's going ballistic over south Alabama lul.

 

[Clancy]

I... don't like the way that looks. Sounding attached from South-Central AL. NAM depicts impressive instability, considering the time of day.

 

[UncleJuJu98]

I... don't like the way that looks. Sounding attached from South-Central AL. NAM depicts impressive instability, considering the time of day.
View attachment 23787View attachment 23788View attachment 23789

Considering the nocturnal jet is well in place with that instability. Yup no good lol. Maybe a game of subtle forcing. With a positive tilt trough , which is dangerous with a almost westerly 500mb

 

[Clancy]

Considering the nocturnal jet is well in place with that instability. Yup no good lol. Maybe a game of subtle forcing. With a positive tilt trough , which is dangerous with a almost westerly 500mb

I know the conventional knowledge is positive tilts being less potent, though the South has had their fair share of significant severe events with positive tilt troughs. The parent low is also going to be close to the action late Sunday into Monday, which may give developing storms a hand in intensification.

 

[JBishopwx]

Sunday.

 

[JBishopwx]

Monday:

 

[UncleJuJu98]

Just taking a little deeper dive while I eat subway.

Pretty good storm forecastor would tell me the 850mb vertical vorticity teamed up with simulated radar is a good indicator for supercells given a good environment. To say nonetheless the 12z Nam is impressive.


looking at the surface theta e, will still have a lot of wiggle room for instability to rise as well, also given being pretty close proximity to the southeast quadrant of the low will aid in that. On top of the nocturnal jet being in place to enhance the shear a tad more. Which you'll probably see rise as we get closer to the event like models typically do; barring any increase in coastal convection or something. The surface lapse rates and overall speed shear is not impressive but, in the south a lot of times that doesn't really matter.

Overall I think we are looking at a potent event if trends like this continue.

 

[UncleJuJu98]

Trey going all in

 

[JBishopwx]

 

[Clancy]

Wind fields are fair down there; I suppose it was just favorable enough for a funnel cloud. Wacky stuff!

 

[akt1985]

I wonder how all the CBS affiliates in the risk area on Sunday are going to handle the potential tornado warnings and the Super Bowl on the same channel?

 

[Clancy]

I wonder how all the CBS affiliates in the risk area on Sunday are going to handle the potential tornado warnings and the Super Bowl on the same channel?

Oh man, I'm already imagining the angry social media posts now.

 

[akt1985]

Oh man, I'm already imagining the angry social media posts now.

If I’m not mistaken, Patrick Mahomes’ hometown of Tyler, Texas is in the risk area on Sunday.

 

[Clancy]

18Z NAM holds serve. >1,000 j/kg CAPE across large parts of AL and GA Monday afternoon. One thing to note, the globals are still signaling solid warm sectors going into Monday. I mention this since as we approached Day 1, the last few setups that crapped out showed less and less moisture return on the Euro and GFS. Wind fields are nothing magical but also more than enough for a tornado threat.

 

[JBishopwx]

Jackson:

These 2 periods are 48-72 hrs out at this time and are in the transition window from the global guidance to the hi-res CAM window. Noting that, we will soon be fully in the window where more details and potential storm mode evolution will be offered. Despite that, trends since yesterday are for a more potent system with a more organized surface low. This will promote more of a northward surge of higher boundary layer moisture and even increase lower level shear, at least for some part of the area. The key feature will be where the front stalls early on Sunday. Will it be closer to I-20 or more like Hwy 84/98 in our far south. The location of this front by midday Sunday will tell the tale for where the developing surface low will track later Sunday night and also the northward extend of the quality boundary layer moisture return and northward push of instability. The SPC day3 outlook covers things well and further refinements may occur as the hi-res window offers more specifics on the evolution of key features. One could be a bit more potential in our N half if the low track is more N. In general, the trend is for the environment to have decent lapse rates (VT of 27-28) and MU/SBcape in the 800-1800 j/kg range. Additionally, the deep effective shear will be 50-65kts. Low level shear is somewhat limited, but this will highly depend on how soon/late the low level jet develops in response to the strong ascent and location of it as well. At this time, our messaging is solid. The only adjustment needed is on timing. The focus looks to be more Sunday night, but ingredients for some severe could be in place by late afternoon. With that, the graphic will be adjusted to narrow the timing to mention late Sunday afternoon into the overnight. Primary time window right now looks to be 4pm to 3am.

 

[Clancy]

Jackson:

Seconding Jackson's comment, the lapse rates look quite favorable for an event this time of year for Sunday and Monday. Not necessarily something we get a whole lot of here in February typically speaking.

 

[warneagle]

A day early but that's a healthy-looking supercell west of LZK