Great Plains, Midwest, & Deep South Storm Season 2021

[Iceresistance]

May 8th (Saturday) looks potent for Kansas & Oklahoma, even though there is a strong cap, but when it breaks . . .

[Iceresistance]

My own 4-10 day outlook for storms

Day 4 (Sunday) - Severe Potential in Eastern Texas & SE Oklahoma, but predictability is too low

Day 5 (Next Monday) - Severe Potential in the Eastern Half of Texas, Along & north of I-10 from Louisiana to Alabama, but predictability is too low

Day 6 (Next Tuesday) - Severe Potential in Southern Texas, but predictability is too low

Day 7 (Next Wednesday) - Potential Too Low

Day 8 (Next Thursday) - Potential Too Low

Day 9 (Next Friday) - Severe Potential in Northern Kansas & Southern Nebraska, but predictability is too low

Day 10 (Next Saturday) - Severe Potential from Eastern Nebraska, SW Iowa, Western Missouri, Eastern 2/3 of Kansas & Oklahoma, & Northern Texas, but predictability is too low & far out

[ElectricStorm]

SPC mentioning upgrades possible for Sat. This is one of those days where if the cap looks like it will break, some of those areas could go from marginal to enhanced very quickly

[Iceresistance]

SPC mentioning upgrades possible for Sat. This is one of those days where if the cap looks like it will break, some of those areas could go from marginal to enhanced very quickly

Or maybe higher . . .

May 3rd, 1999 Outbreak was originally not going to happen, until a sounding showed an EXTREMELY FAVORABLE environment, some areas went from a Marginal to HIGH risk in one update!

[NXStumpy_Robothing]

Looks like we may have some action today after all.

 https://twitter.com/NWSSPC/status/1390322035876765696

[Iceresistance]

This setup this Saturday is going to be very hard to forecast to see if the storms will blow up or not . . .

Sounding near Norman, OK


Sounding near Tecumseh, OK

[ElectricStorm]

SPC mentioning upgrades possible for Sat. This is one of those days where if the cap looks like it will break, some of those areas could go from marginal to enhanced very quickly

Or maybe higher . . .

May 3rd, 1999 Outbreak was originally not going to happen, until a sounding showed an EXTREMELY FAVORABLE environment, some areas went from a Marginal to HIGH risk in one update!

Sleeper events can be pretty insane for sure. The biggest one ive had over here during my lifetime was 5/22/19. General T-storm on Day 3, marginal on Day 2, moderate on Day 1. I have noticed that besides the maxed out parameter days (like 5/10/10 or 5/24/11) the bigger days recently have been from events that haven't looked "big" until a few days before or even the day of. Most of the time lately, the days highlighted a week in advance don't turn out big like they could have (4/26/16, 5/2/18, and 4/27/21 come to mind, and there's a bunch of others). Saturday is either going to be big, or nothing at all...

[Iceresistance]

12z GEFS Mean SCP
(Highest is 11 near Perry, OK)



Max SCP (Highest is 25 in the OKC Metro)

[Iceresistance]

See we are close to an area of 30+ SCP. Wow though you are near the bullseye.

Central Oklahoma is almost always the target for something like this . . .

Yep. And then us over here get the leftovers lol. Most of the time anyway, there are always a few exceptions.

Well, there is a BIG one! Lol



SCP of a 27 just east of Tulsa & Broken Arrow!

[InfernoFlameCat]

I hope we get something bbig out of this. A nice plains outbreak would be great

[ElectricStorm]

When it comes to Saturday, I'm on the border on what to expect. If this were any other month besides May, I wouldn't really expect much at all, as moisture won't be great and of course that cap is a big concern. But considering what we've seen already this month with all these overachieving marginal/slight risk days, it looks to me like we are in a pretty favorable background state for storm development right now. Heck even today wasn't upgraded to slight risk until the 1630z outlook and we're sitting at nearly 100 wind reports and 6 tornado reports for today. Right now the models still don't show the cap breaking anywhere south of Kansas, but keep in mind they didn't show storms firing in TX Monday until right before the event, so I'm sure that will change as we get closer. For now, I think the first Day 2 outlook will look very similar to the current Day 3 outlook, but I could definitely see some potential upgrades in later outlooks.

Lots of big potential, lots of bust potential...

Also would like to point out that the 0z GFS is now firing storms in TX. Nothing in OK on this run but this could be a sign that it's trending towards a more breakable cap.

[Iceresistance]

When it comes to Saturday, I'm on the border on what to expect. If this were any other month besides May, I wouldn't really expect much at all, as moisture won't be great and of course that cap is a big concern. But considering what we've seen already this month with all these overachieving marginal/slight risk days, it looks to me like we are in a pretty favorable background state for storm development right now. Heck even today wasn't upgraded to slight risk until the 1630z outlook and we're sitting at nearly 100 wind reports and 6 tornado reports for today. Right now the models still don't show the cap breaking anywhere south of Kansas, but keep in mind they didn't show storms firing in TX Monday until right before the event, so I'm sure that will change as we get closer. For now, I think the first Day 2 outlook will look very similar to the current Day 3 outlook, but I could definitely see some potential upgrades in later outlooks.

Lots of big potential, lots of bust potential...

Also would like to point out that the 0z GFS is now firing storms in TX. Nothing in OK on this run but this could be a sign that it's trending towards a more breakable cap.

It's either GO BIG OR BUST!

But either way, the SPC said the the uncertainly is so high, that the Marginal risk is only possible for this . . .

[ElectricStorm]

Shoutout to the 18z GFS for giving us some great long range entertainment

[Iceresistance]

Shoutout to the 18z GFS for giving us some great long range entertainment

In the short term, the SCP is looking crazy, but again, the STPC (Significant Tornado Parameter Composite) is nonexistent or too low . . .

But however, the 18z NAM tries to fire off some cells along the dryline in Texas & Western Oklahoma, it's going to be a very hard forecast . . .

[Iceresistance]

Radar is showing a really potent cluster of storms in Panhandle Texas . . .

[Cpv17]

Too much zonal flow going on. Need some deep troughing out west.

[ElectricStorm]

I'm thinking KS has a decent day tomorrow, with everything south of that being meh. Although it's hard for me to buy the HRRR solution right now, as I think it might be under-doing moisture a bit. The NAM tries to fire some storms on the dryline. I usually trust the HRRR more than the NAM, so it will be interesting to see which one end up being right. I think the HRRR no-storm south of KS solution is possible, but I see it more as a cap issue and not a moisture issue.

[ElectricStorm]

I'm thinking KS has a decent day tomorrow, with everything south of that being meh. Although it's hard for me to buy the HRRR solution right now, as I think it might be under-doing moisture a bit. The NAM tries to fire some storms on the dryline. I usually trust the HRRR more than the NAM, so it will be interesting to see which one end up being right. I think the HRRR no-storm south of KS solution is possible, but I see it more as a cap issue and not a moisture issue.

I take this back. Observed soundings from southern TX show horrible moisture coming in... Still should see some decent storms in KS though

[ElectricStorm]

Enhanced risk for wind is up in KS

[Ntxw]

Too much zonal flow going on. Need some deep troughing out west.

It's a lot of NW flow vs SW flow thanks to the persistent blocking in the high latitudes. Cooler air has been an issue amongst trough shearing out due to Lakes low.