April 27-May 6, 2022 | Tornado Outbreak Sequence

[Neoncyclone]

Time for some CAM action, event is a couple hours out now most of these are 12z except for the HRRR which is 17z

WRF-ARW

WRF-NSSL

HRW-FV3

[Neoncyclone]

4 minutes ago, StormfanaticInd said:

Instability is building 👀

Central and SW Oklahoma already uncapped as well

[Chinook]

I saw a bit of lightning here in Colorado. First lightning I've seen in... an infinite amount of time.

[Ingyball]

So it does appear that the storms last night did leave a boundary here. Seeing some concerning in house NWS products that can't be shared publicly afaik.  

[ClicheVortex2014]

8 minutes ago, Neoncyclone said:

Central and SW Oklahoma already uncapped as well

Always worth the reminder that mesoanalysis is based on the RAP... a very outdated model. It's good for general purposes but I don't always trust its instability/cinh output

[ClicheVortex2014]

Case and point... 18z OUN sounding shows a moderate cap. Rest of the sounding is still loading but we got the gist.

[Ingyball]

Gonna be one of those days where I wish we launched a balloon here at ICT lol. 

[ClicheVortex2014]

4 minutes ago, Ingyball said:

Gonna be one of those days where I wish we launched a balloon here at ICT lol. 

Just go to Walmart and buy some balloons

[ClicheVortex2014]

With the 18z OUN sounding in, here's 18z HRRR. It may be just a Kansas day. It's got one long-lived supercell which should have good radar representation BUT would move through some populated towns.

If this was anywhere but the Plains, I'd be concerned about qlcs tornadoes but it looks like 0-3km instability will be pretty damn weak by that time. 60-70 knot LLJ is pretty nasty though. Widespread damaging winds with wind-driven hail should be prevalent.

Edited April 29, 2022 by ClicheVortex2014

[Neoncyclone]

 

[ElectricStorm]

I still don't think we'll see much here in C OK, that cap at 18z is going to have to erode a ton to get anything. Tulsa and north though I'm pretty concerned about. 

Looks like the first watch is up for KS/NE. 60/50 tor probs and some pretty high wind and hail probs 

 

[Ingyball]

Here's that first Tor watch, like OKwx said pretty high probs. 

[ClicheVortex2014]

4 minutes ago, OKwx_2001 said:

I still don't think we'll see much here in C OK, that cap at 18z is going to have to erode a ton to get anything. Tulsa and north though I'm pretty concerned about. 

Looks like the first watch is up for KS/NE. 60/50 tor probs and some pretty high wind and hail probs 

 

Given how much daytime heating you have left, I think you have a shot at breaking the cap. I wouldn't be expecting it to happen but I also wouldn't be shocked. You've got a strong low creating additional mixing via the surface winds, and we're less than 2 months away from the Summer equinox. 

Tornado watch coming for most of our Plains members

   Mesoscale Discussion 0582
   NWS Storm Prediction Center Norman OK
   0223 PM CDT Fri Apr 29 2022

   Areas affected...east-central Kansas into north-central Oklahoma

   Concerning...Severe potential...Tornado Watch likely 

   Valid 291923Z - 292200Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Monitoring for supercell development along the dryline
   this afternoon. Strong tornadoes, very large hail, and damaging
   gusts will all be possible with this activity. A Tornado Watch will
   likely be needed for parts of the area.

   DISCUSSION...Water vapor imagery indicates a strong midlevel speed
   maximum approaching KS/OK, where modest midlevel height falls are
   occurring. As this speed maximum continues overspreading the area, a
   NNE-SSW oriented dryline will sharpen across east-central KS into
   north-central OK. The strengthening dryline circulation, combined
   with south-southwesterly low-level flow oriented largely parallel to
   the dryline should allow for isolated convective initiation between
   20Z-23Z. Surface dewpoints in the middle/upper 60s F beneath very
   steep midlevel lapse rates will support a strongly unstable airmass
   (MLCAPE nearing 3000 J/kg), while effective bulk shear increases to
   around 40 knots. These factors, coupled with strongly veering wind
   profiles in the boundary-layer (200-300 m2/s2 effective SRH) would
   certainly favor supercells capable of strong tornadoes, very large
   hail, and damaging gusts. There is still some uncertainty in the
   overall coverage and location of the severe threat, though trends
   will continue to be monitored for Tornado Watch issuance for parts
   of this area.

 

Edited April 29, 2022 by ClicheVortex2014

[Chinook]

A couple of rain showers have developed by Garden City Kansas, where the unstable air mass, to the north, is moving south a bit into the dry air mass. It's kind of a backwards dryline scenario

[Iceresistance]

Count me out, I'm currently in Little Rock

[Iceresistance]

18z OUN sounding has a weaker cap, it's stronger higher up.

 

Is it weaker than expected?

[ClicheVortex2014]

Looks to me that the inversion is stronger than expected, but dew point is 1 degree higher than expected.

18z HRRR sounding for OUN

Observed sounding

[ClicheVortex2014]

6 minutes ago, ClicheVortex2014 said:

Looks to me that the inversion is stronger than expected, but dew point is 1 degree higher than expected.

18z HRRR sounding for OUN

Observed sounding

I'm dumb. I posted the 18z HRRR even though that same 18z sounding was ingested into the run. So that's a pointless comparison for seeing if the cap is stronger/weaker than expected. Basically seeing the observed SPC sounding on HRRR, but literally wrong.

Here's 17z HRRR for 18z OUN. Dew point was observed to be 2 degrees higher, temp 1 degree higher, cap is weaker than observed.

Edited April 29, 2022 by ClicheVortex2014

[Neoncyclone]

8 minutes ago, ClicheVortex2014 said:

Looks to me that the inversion is stronger than expected, but dew point is 1 degree higher than expected.

18z HRRR sounding for OUN

Observed sounding

pretty incredible accuracy between observed and forecasted hodographs

[ClicheVortex2014]

3 minutes ago, Neoncyclone said:

pretty incredible accuracy between observed and forecasted hodographs

I was thinking the same thing and then I realized what I was looking at. See the following post.

Basically, the 18z OUN sounding was fed into 18z HRRR. So the HRRR should show exactly what was observed with the 18z sounding. That's a big part of doing balloon launches; get observed data in order to feed to the models so they can simulate what may happen. The other part is to observe how the winds/temps/moisture aloft is coming along.

It's close, but not quite there.

Edited April 29, 2022 by ClicheVortex2014

[Neoncyclone]

2 minutes ago, ClicheVortex2014 said:

I was thinking the same thing and then I realized what I was looking at. See the following post.

Basically, the 18z OUN sounding was fed into 18z HRRR. So the HRRR should show exactly what was observed with the 18z sounding. That's a big part of doing balloon launches; get observed data in order to feed to the models so they can simulate what may happen. The other part is to observe how the winds/temps/moisture aloft is coming along.

It's close, but not quite there.

I never realized that they did that, that's awesome

[snowlover2]

Potentially busy night ahead i see.

[ClicheVortex2014]

12 minutes ago, Neoncyclone said:

I never realized that they did that, that's awesome

It really is. That's why NWS offices in a specific region will launch balloons at 18z/6z in advance of/during major events like a high-end tornado outbreak, winter storms, or hurricane. Offices on the west coast even participate when it's a winter storm or tornado outbreak since the system usually enters through the west coast.

Edited April 29, 2022 by ClicheVortex2014

[ClicheVortex2014]

Getting some cumulus along the dryline now

[ElectricStorm]

HRRR starting to show a supercell in OK now