Severe Weather 2025

[ColdFront]

Was 5/31/1985 a large longwave, or was that a different setup entirely? That one seems to stand out to me as a strange mega outbreak that occurred really late in the season, unusually displaced well into the northeast.

I’m on mobile, but https://tornadoarchive.com/home/ will let you run a re-analysis of the 500 MB pattern for that day.

My guess is it was a huge long wave through as it advected a pretty significant EML over top of the warm sector area. It was just an anomalous event. I would expect something like that in early to mid spring, not late May for that area.

You can read more about the set up here:

May 31, 1985 Tornado Outbreak: 35th Anniversary

 

[Shakespeare 2016]

How many times has that happened. I don't think I can recall back to back 30% for days 7 and 8

I am not sure if it has happened either. It was just a dream.

 

[Clancy]

SPC expects congealing segments into the early evening, with attendant wind and large hail threat. Several SVAs are in effect.

Mesoscale Discussion 0746
NWS Storm Prediction Center Norman OK
0343 PM CDT Thu May 08 2025

Areas affected...the Tennessee Valley Vicinity

Concerning...Severe Thunderstorm Watch 238...239...240...

Valid 082043Z - 082215Z

The severe weather threat for Severe Thunderstorm Watch 238, 239,
240 continues.

SUMMARY...The ongoing large hail/damaging wind threat will continue
through the late afternoon and into the evening.

DISCUSSION...A broad region of moderate instability and moderate
shear is present from central Kentucky southward into northeast
Mississippi to the Appalachians. Within this area, multiple
supercells have developed with reports of 1 to 2 inch hail. The
environment across the region remains favorable through the
remainder of the afternoon and into the evening. Therefore, ongoing
supercells will likely continue with additional development also
possible. The threat has been mostly hail thus far given the more
discrete mode. However, as storms coverage increases, expect
clusters and potential bowing line segments to develop. This would
result in a greater damaging wind threat this evening.

..Bentley.. 05/08/2025

Storm Prediction Center Mesoscale Discussion 746

Severe weather, tornado, thunderstorm, fire weather, storm report, tornado watch, severe thunderstorm watch, mesoscale discussion, convective outlook products from the Storm Prediction Center.

www.spc.noaa.gov

 

[Clancy]

Big time hail on its way to Columbus, MS right now. Warning is for golf balls, but it could be larger.

 

[Ledian]

This storm caused a tree to fall on a house in Maben, so i'm definitely monitoring it. Hopefully all my family in Columbus is alright after this passes.

 

[tennessee storm chaser]

Yeah. Like I said, it’s not entirely unprecedented (one example would be June 2-3, 1990 Ohio Valley outbreak), but it’s not common and is actually rare. Another good example would be the late May 2011 high risk east of the plains.

May 25. 2011

 

[Grand Poo Bah]

Holy $hit. 12z HRRR coming in HOT with the CAPE. It's showing 6500 over Oklahoma and Kansas on Wednesday, AND UP TO 6859 ON THURSDAY! I've never seen this before and it's kind of blowing my F'ing mind. Consider me straight up gobsmacked.

 

[Grand Poo Bah]

Euro is very bullish on this set up. Can't pull soundings so here's GIFs of each element for 7 days starting on Wednesday. Notice how the warm sector just keeps getting pounded and recovering immediately.

MUCAPE



Sheer



Moisture/ Dew points



Vorticity



Thanks to me accidentally posting the 0Z earlier I can confidently say the Euro is trending very aggressively in a bad direction.

 

[tennessee storm chaser]

Euro is very bullish on this set up. Can't pull soundings so here's GIFs of each element for 7 days starting on Wednesday. Notice how the warm sector just keeps getting pounded and recovering immediately.

MUCAPE

View attachment 41093

Sheer

View attachment 41094

Moisture/ Dew points

View attachment 41095

Vorticity

View attachment 41096

Thanks to me accidentally posting the 0Z earlier I can confidently say the Euro is trending very aggressively in a bad direction.

Definitely has my attention least western portion of the mid south …..

 

[Atlantic]

Euro is very bullish on this set up. Can't pull soundings so here's GIFs of each element for 7 days starting on Wednesday. Notice how the warm sector just keeps getting pounded and recovering immediately.

MUCAPE

View attachment 41093

Sheer

View attachment 41094

Moisture/ Dew points

View attachment 41095

Vorticity

View attachment 41096

Thanks to me accidentally posting the 0Z earlier I can confidently say the Euro is trending very aggressively in a bad direction.

As in trending towards a 3/14-3/16-type? I really hope it falls apart.

 

[Grand Poo Bah]

Definitely has my attention least western portion of the mid south …..

GFS has at least trended down a ton in the last few runs.

 

[Grand Poo Bah]

As in trending towards a 3/14-3/16-type? I really hope it falls apart.

I definitely don't think so. Lots of very strong elements that aren't quite aligning the way they need to right now. 3/14-3/16 was a perfect set up. I'd call this one very chaotic as of now. Looking forward to seeing what the METs think about it..

 

[Atlantic]

I definitely don't think so. Lots of very strong elements that aren't quite aligning the way they need to right now. 3/14-3/16 was a perfect set up. I'd call this one very chaotic as of now. Looking forward to seeing what the METs think about it..

Same here. I saw a post earlier saying this is the peak of tornado season. Is May the peak of the season?

 

[Grand Poo Bah]

Same here. I saw a post earlier saying this is the peak of tornado season. Is May the peak of the season?

That was also me, and overall, yes it is. The south peaks more in April, and the North has a lot of activity in June, but basically everywhere is in play in May.

 

[UncleJuJu98]

18z GFS says what long wave trough? LUL

 

[Aaron Rider]

I’m on mobile, but https://tornadoarchive.com/home/ will let you run a re-analysis of the 500 MB pattern for that day.

My guess is it was a huge long wave through as it advected a pretty significant EML over top of the warm sector area. It was just an anomalous event. I would expect something like that in early to mid spring, not late May for that area.

You can read more about the set up here:

May 31, 1985 Tornado Outbreak: 35th Anniversary

Another good read on 5/31/85: https://stormstalker.wordpress.com/2022/06/08/may-31-1985-the-united-states-canada-outbreak/

Trey from Convective Chronicles expressed his intention to do a video on the outbreak.

There has never been anything like it before or since, that we know of, in the areas affected. Anomalous indeed.

Edit: Forgot a good WeatherBox video on the matter

 

[Aaron Rider]

That was also me, and overall, yes it is. The south peaks more in April, and the North has a lot of activity in June, but basically everywhere is in play in May.

View attachment 41098

It's not just that the South peaks in April (or, in many years, March), it's that the overall violence of the storms down there peaks before May as well. May sees roughly half as many tornadoes in Alabama, for example, as April but far fewer violent tornadoes. This disparity obviously decreases as you go further north (e.g. Kentucky, North Carolina) but is still generally true.

The famous central Alabama F4 (Brent, Greensboro, etc) back in 1973 was very late in May, though.

 

[JPWX]

There were multiple times in May 2003 where North MS had multiple Moderate Risk days as well. Of course, May 2003 was very active. 2003, 2011, and other handful of years in May still had Mid-South/Deep South significant severe weather outbreaks. So it's not all Hey, it's May so we need to move all the tornadoes to Tornado Alley. CPC is hinting at it too now.

 

[Clancy]

There were multiple times in May 2003 where North MS had multiple Moderate Risk days as well. Of course, May 2003 was very active. 2003, 2011, and other handful of years in May still had Mid-South/Deep South significant severe weather outbreaks. So it's not all Hey, it's May so we need to move all the tornadoes to Tornado Alley. CPC is hinting at it too now.

It's definitely something that bears watching. I would have to assume the lower incidence of intense tornadoes during May in the Southeast has a lot to do with most tornadoes being generated mostly by summertime-style MCS events, like the one we had a few days ago. It seems like we tend to have a lot of glancing blows by the more mid-latitude troughs which can give the Plains and Midwest major events, but leave us farther from the greatest axis of kinematics. That said, I'm hoping any upcoming troughs and associated shortwaves stay far away from here, as there will be no shortage of thermos or moisture to be had over the next 1-2 weeks.

 

[Grand Poo Bah]

I found this really cool resource with soundings from basically every major severe weather event of the last 25 years. Some (probably obvious) trends I'm noticing are dry air aloft in the 700-500 mb range and high CAPE makes SRH less important. Likewise, CAPE is less important when helicity and sheer are really high (3-14/15 comes to mind). Strong tornadoes also seem to be pretty rare when effective sheer is outside the 40-80kt range.

[Retired] Case Archive - ustornadoes.com

Soundings, hodographs, and much more. Case synopses on some of the most well known U.S. tornadoes of the 2000s. Over 200 events examined.

www.ustornadoes.com