March 30-April 1, 2023 | Severe Weather | Destructive Tornado Outbreak with a double High Risk

[Iceresistance]

Here we go again for Round #4, SPC has this, but too much uncertainty for now.

 

 Guidance continues to indicate that a deep upper low will move into
   the western CONUS on D7/Wednesday and D8/Thursday. Moisture return
   across the Plains is anticipated ahead of this system, and some
   severe appears possible across the Plains on D8/Thursday. However,
   timing of the wave and quality of the moisture return are uncertain,
   and low predictability limits forecast confidence at this range.

 

[StormfanaticInd]

18z gfs and euro are strongly hinting at this possibility.

[StormfanaticInd]

6 minutes ago, StormfanaticInd said:

18z gfs and euro are strongly hinting at this possibility.

18z gfs is pretty scary

[Iceresistance]

Uh oh, already on D7?
 

   Mid/upper ridging will develop over the Plains and MS Valley
   vicinity on Day 6/Wed ahead of a deepening western trough.
   Strengthening surface low pressure over the southern Rockies
   vicinity Wednesday evening/overnight will result in northward
   transport of Gulf moisture across TX/OK by early Day 7/Thu. Severe
   potential will increase on Day 7/Thu from the southern Plains
   vicinity as the upper trough develops eastward. There is still
   uncertainty regarding the timing and geometry (negative vs. positive
   tilt) of the trough. However, forecast guidance shows strong
   southwesterly flow overspreading the southern Plains vicinity atop a
   seasonally moist boundary-layer ahead of a dryline and
   southeastward-advancing cold front. This overall pattern will
   support severe thunderstorms, though the 15 percent outlook
   delineation may shift/expand as forecast details evolve in the
   coming days.

   Some severe potential may persist eastward toward the Mid/Lower MS
   Valley vicinity on Day 8/Fri. However, stronger ascent appears to
   become further removed from better thermodynamics with time as the
   upper trough ejects quickly northeast toward the Great Lakes. Trends
   will be monitored for any increasing severe potential on Friday over
   the coming days.

Friday may get a D4-8 slight risk but Thursday is looking crazier.

[StormfanaticInd]

 

[ClicheVortex2014]

12z Euro has a slower solution and pushes a severe threat into the Texas Panhandle

[Iceresistance]

3 hours ago, ClicheVortex2014 said:

12z Euro has a slower solution and pushes a severe threat into the Texas Panhandle

SPC took note of that, Amarillo is now under the Slight risk for Thursday.

[Ingyball]

I like the potential for this setup. Good upper trough setup with the 500mb trough taking on a neutral to negative tilt. GFS is still fast but the 18z run came in even slower. 12z Canadian had some nasty soundings, especially for a potential morning event. (soundings near Wichita and northeast Kansas). EFI is hinting that the above normal CAPE and CAPE + Shear, which for late March can be a big deal. 

 

[Ingyball]

12z Euro is pretty impressive too for eastern Kansas. Would not be surprised to see an expansion of the 15% and perhaps a 30% introductions if the 0z runs continue to support an outbreak. 

 

 

[ClicheVortex2014]

Im on day shifts this week so whether we get severe weather or fire weather, I’m in a good spot for getting some overtime. 00z GFS for Friday has 35-40 mph sustained winds, gusting in the 50s, with <15% RH. 

[ElectricStorm]

I always take these Day 6-7 plains systems with a grain of salt since a lot of times they tend to downtrend as we get closer. But this definitely looks interesting and for sure needs to be watched. It's certainly got some potential. 

CIPS analogs are in range now and so far they're not really impressive, although somehow 5/3/99 made it on there. It's still in the far range of the run so they'll likely change quite a bit as we get closer.

https://www.eas.slu.edu/CIPS/ANALOG/DFHR.php?reg=SP&fhr=F120&rundt=2023032600&map=thbSVR

Edited March 26, 2023 by ElectricStorm

[Ingyball]

7 hours ago, ElectricStorm said:

I always take these Day 6-7 plains systems with a grain of salt since a lot of times they tend to downtrend as we get closer. But this definitely looks interesting and for sure needs to be watched. It's certainly got some potential. 

CIPS analogs are in range now and so far they're not really impressive, although somehow 5/3/99 made it on there. It's still in the far range of the run so they'll likely change quite a bit as we get closer.

https://www.eas.slu.edu/CIPS/ANALOG/DFHR.php?reg=SP&fhr=F120&rundt=2023032600&map=thbSVR

CIPS does some wonky stuff with some of these dates if you just look at the SPC reports. For example, March 26th was a pretty big outbreak in 1991 (That got overshadowed a month later).

"An outbreak produced 50 tornadoes over a two day span. An F4 tornado passed near Hutchinson, Kansas on March 26, while two people were killed by tornadoes in Wisconsin and Indiana on March 27. After only two weak F0 tornadoes touched down on March 28, another outbreak of 21 tornadoes struck the Southeastern United States on March 29.^[5] An F1 tornado struck Munford, Alabama, where it destroyed several trailer homes, killing five people, four of them in one family.^[6] An F3 tornado moved through Clarkdale, Georgia, destroying 15 townhouses, damaging 120 others, and injuring 25 people.^[7] An F2 tornado destroyed 16 homes and heavily damaged 39 others in Ladonia, Alabama, injuring 16 people.^[8] In all, 73 tornadoes touched down during the outbreak sequence"

 

[Ingyball]

06z GFS would be interesting with how fast the 500mb trough intensifies, but the upper trough is poorly oriented over Kansas and Missouri compared to previous runs. Would still interesting over Oklahoma and Arkansas in that setup. 

[Sentinel]

From MS:

https://www.bbc.com/news/av/world-us-canada-65080552

[Iceresistance]

There is no 30% yet for Thursday, but there is a 15% area for Friday.

[StormfanaticInd]

Solid severe chances this Thursday and Friday. 

[Iceresistance]

8 hours ago, ElectricStorm said:

I always take these Day 6-7 plains systems with a grain of salt since a lot of times they tend to downtrend as we get closer. But this definitely looks interesting and for sure needs to be watched. It's certainly got some potential. 

CIPS analogs are in range now and so far they're not really impressive, although somehow 5/3/99 made it on there. It's still in the far range of the run so they'll likely change quite a bit as we get closer.

https://www.eas.slu.edu/CIPS/ANALOG/DFHR.php?reg=SP&fhr=F120&rundt=2023032600&map=thbSVR

Ah yes, that was the site I was looking for! 😛 

[Central Illinois]

Looks like a good shot at severe weather here friday!

[ClicheVortex2014]

Wrong thread of course

 

Edited March 26, 2023 by ClicheVortex2014

[Ingyball]

Getting concerned about the post dryline environment. 12z GFS had us mixing to the 500mb layer and interacting with a 100kt jet streak. Reminds me of December 15th 2021 with that trough orientation but further south. 

[Ingyball]

GFS wind gust for Friday afternoon. Pretty impressive this far out. 

[snowlover2]

Pretty large day 5 enhanced area.

Quote

Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0336 AM CDT Mon Mar 27 2023

   Valid 301200Z - 041200Z

   ...DISCUSSION...
   An upper trough will shift east across the western U.S. to the
   central/southern Rockies on Day 4/Thu. Forecast guidance has come
   into better agreement with a slower eastward ejection of the trough.
   As such, the 15 percent severe area for Thursday has been shrunk
   compared to previous days. Some severe potential, albeit more
   conditional, will still exist as strong surface cyclogenesis occurs
   over the central High Plains. In response to this developing low,
   strengthening southern low-level flow across the southern/central
   Plains will transport upper 50s to mid 60s F dewpoints across
   TX/OK/KS to the east of a dryline. Large-scale ascent is expected to
   be modest as the main trough remains too far west. However, strong
   vertical shear will overlap a moderately unstable airmass. If
   thunderstorms can develop/overcome capping, isolated supercells
   capable of all hazards will be possible in the vicinity of the
   dryline from late afternoon into Thursday night.

   By Day 5/Fri, all-hazards severe potential will expand across a
   large portion of the central U.S. There is still some uncertainty in
   timing and intensity of the ejecting upper trough. Nevertheless, a
   broad warm sector is expected to develop from eastern portions of
   the southern Plains toward the Mid/Lower MS Valley through the
   afternoon, and eastward to the Lower OH/TN Valley vicinity by
   evening/overnight. Intense southwesterly mid/upper flow will overlap
   the warm sector as a cold front tracks east/southeast. The severe
   threat could end up taking a bi-modal character, with an area of
   enhanced potential focused near a strong surface low over the IA/IL
   vicinity, and another area focused further south toward the
   Mid-South where large-scale ascent will be weak, but a better
   thermodynamic environment will overlap with strong shear. However,
   enough differences exist in forecast guidance regarding the location
   of the surface low track and amplitude of the ejecting upper trough
   that a broad 15 and 30 percent severe delineation has been
   introduced. These areas will likely change some in the coming days
   as forecast details become better resolved.

   Severe potential could continue eastward toward the Mid-Atlantic and
   Southeast on Day 6/Saturday. A moist boundary-layer will exist
   across these areas ahead of the east/south advancing cold front.
   However, timing and location of the surface low and focus of strong
   shear/large-scale ascent is uncertain, and predictability is too low
   to delineate any areas at this time.

   Large spread in forecast guidance continues/increases during the end
   of the forecast period, and predictability remains low on Days
   7-8/Sun-Mon.

   ..Leitman.. 03/27/2023

 

[StormfanaticInd]

58 minutes ago, snowlover2 said:

Pretty large day 5 enhanced area.

 

Looking like our first outbreak of the spring for the OV

[Iceresistance]

D4 may not happen due to the cap.

[StormfanaticInd]