December 29-January 3, 2022-23 | Tornado Outbreak | Day 1 & 2 Enhanced Risk

[Sentinel]

Happy new year! 

[ClicheVortex2014]

Greatest threat is, imo, pretty clearly in E TX and specifically the ArkLaTex tristate area. Great overlap between where CAMs have convection and where the greatest parameters are.

Edited January 1, 2023 by ClicheVortex2014

[ClicheVortex2014]

12z hrrr has some warm sector surface wind convergence, providing semi-discrete convection in the ArkLaTex area. Strong tornado threat would go up to Fort Smith. 
 

Storm mode gets messier as midnight approaches, but still room for cells on the far southern part of the broken line. Gotta keep an eye on what happens with the squall because it looks like it lifts northeast in the morning hours, leaving the day 3 slight risk untouched.

Nasty start to the 12z suite. Hopefully other CAMs don’t follow.

Edited January 1, 2023 by ClicheVortex2014

[Neoncyclone]

18z HRRR hints at that squall pushing a bit north as Cliche mentioned to watch out for last night.

 

Edited January 1, 2023 by Neoncyclone

[ClicheVortex2014]

23 minutes ago, Neoncyclone said:

18z HRRR hints at that squall pushing a bit north as Cliche mentioned to watch out for last night.

 

Yeah I was about to post that loop. Tuesday looks scarier than tomorrow on that run.

Warm sector is pretty far removed from the jet streak/tilt on both days but you can't sleep on days with trough positions like this.

Edited January 1, 2023 by ClicheVortex2014

[ClicheVortex2014]

Something to keep an eye on in future runs. 90 sigtor contour is being teased for tomorrow

[ClicheVortex2014]

 

[ClicheVortex2014]

Wild AFD from SHV. Highly impactful event for them

This above fact introduces a bit of uncertainty into the forecast
for tomorrow into tomorrow night as a potent upper level
disturbance approaches. A good deal of synoptic lift produced by
this disturbance and increasing southerly warm air advection into
our area should get showers and thunderstorms going by late
morning to early afternoon across central and eastern zones. This
early activity will probably have available instability somewhat
compromised by lower clouds, although at least 1000 j/kg of MLCAPE
should still be present to fuel vigorous updrafts. The early
activity will also not be occurring in the best "wind shear
window" - which should be more in the time neighborhood of late
afternoon into the early evening. All the above said, there will
still be severe potential (hail/wind/lower-end risk of tornadoes)
with these initial storms, while these storms will also be capable
of dumping rainfall very quickly.

So the severe weather risk from the Storm Prediction Center for
our area tomorrow into tomorrow night has not changed, with a
large majority of our CWA outline in an ENHANCED RISK with all
severe weather hazards possible. In the Enhanced Risk area, the
SPC still is highlighting a 10% percent risk of strong tornadoes
within 25 miles of a point. The initial storms expected, as
described above, will likely pose less risk of strong tornadoes
than will be the case by late afternoon into early evening. At
that time, there is decent high resolution model consensus of
thunderstorms, with at least some being problematic supercells,
breaking out in western zones near a dryline advancing just ahead
of an approaching cold front. The wind shear environment in this
time/space will be more favorable for tornadoes and other severe
weather hazards, although fine-scale aspects of favorable
hodograph curvature and also ultimate thermodynamic
destabilization might be compromised a bit by earlier convection.
This is the uncertainty alluded to earlier. But assuming these
aspects are not too compromised, expect this severe activity to
advance eastward through the heart of the region during the
evening hours, eventually congealing into a line of storms (QLCS)
in the Arklamiss vicinity toward midnight or the early morning
hours. Once this happens, the potential for strong tornadoes
should decrease, although the risk of some tornadoes embedded
within the line will remain. All activity may not clear the region
until after daybreak on Tuesday, but by that time the much more
unidirectional wind shear will be lowering overall severe
probabilities with the storms in the far southeastern portion of
the region.

Due to at least a few different rounds of convection expected from
late morning tomorrow through tomorrow night, outlining a tight
timing window of severe potential for tomorrow is a bit difficult.
However, the potential for multiple rounds of convection, and an
organizing late squall line slow to exit, opens the door for
excessive rainfall - especially considering the air mass we will
be dealing with should be very anomalously moist for early
January. In consideration of these things, and the fact much of
our region experienced heavy rainfall late last week, we have
issued a Flood Watch for most areas (aside from far northwestern
zones) from noon tomorrow through daybreak Tuesday morning. A
widespread 1 to 2 inches of rain is anticipated, but it will be
likely pockets of 3+ inches of rain through the event which will
yield the higher flooding concern.

 

[ClicheVortex2014]

RAP is showing Monday's parameters on a larger scale on Tuesday. Of course, we don't exactly know how convection will evolve tomorrow. Could be debris clouds/warm sector rain that messes things up.

[Iceresistance]

The HRRR UD Heilicy Swath has a noticeable west trend compared to other runs, towards me! 

[ClicheVortex2014]

0z HRRR is pretty wild for the OV. Wow.

[Iceresistance]

21 minutes ago, ClicheVortex2014 said:

0z HRRR is pretty wild for the OV. Wow.

Makes you wanting to wish that you've never left the OV. But that offsets you being in Amarillo, TX being part of the NWS!

[ClicheVortex2014]

12 minutes ago, Iceresistance said:

Makes you wanting to wish that you've never left the OV. But that offsets you being in Amarillo, TX being part of the NWS!

I'm gonna miss events like this in the winter and MCSs in the summer, but the spring will make up for it. Winter also isn't bad because the wind makes it interesting.

[Iceresistance]

4 minutes ago, ClicheVortex2014 said:

I'm gonna miss events like this in the winter and MCSs in the summer, but the spring will make up for it. Winter also isn't bad because the wind makes it interesting.

Yep, that wind is always crazy in the Fall through Spring. Last Year was a different animal with almost nonstop wind!

[ClicheVortex2014]

I've had the 4am shift for the past 5(?) days, but I have the next 2 days off. Good timing because I'll be able to watch radar all day, but I'm probably gonna sleep til just before the outbreak starts. Also, I'm going to have a serious conflict when the Bengals-Bills game starts. 

Only thing that SPC could do to surprise me with the outlooks for tomorrow is go high risk or slight risk. This feels like a solid enhanced or moderate risk event, nothing more nothing less.

Edited January 2, 2023 by ClicheVortex2014

[Iceresistance]

2 minutes ago, ClicheVortex2014 said:

I've had the 4am shift for the past 5(?) days, but I have the next 2 days off. Good timing because I'll be able to watch radar all day. But I'm going to have a serious conflict when the Bengals-Bills game starts. 

Only thing that SPC could do to surprise me with the outlooks for tomorrow is go high risk or slight risk. This feels like a solid enhanced or moderate risk event, nothing more nothing less.

The only thing that will trigger the High Risk is a sudden and very rapid increase of the instability. And the downgrade when the shear becomes very unfavorable. 

 

Also, why not have the NFL game on a different screen so the interference won't be as bad?

[ClicheVortex2014]

5 minutes ago, Iceresistance said:

The only thing that will trigger the High Risk is a sudden and very rapid increase of the instability. And the downgrade when the shear becomes very unfavorable. 

 

Also, why not have the NFL game on a different screen so the interference won't be as bad?

Agreed about instability, but also would need greater confidence for a larger window for semi-discrete/discrete supercells. I don't see that happening with this one.

I'll certainly have GR2 and the Bengals game on, but my attention will certainly be split at best. Hopefully the event is winding down by the time that game starts.

Edited January 2, 2023 by ClicheVortex2014

[ClicheVortex2014]

Sounds like they considered a moderate risk but there's concern about storms weakening destabilization before the best overlap of the next round/storm mode and low-level shear exists. I've been up for almost 24 hours so my reading comprehension might be off.

 Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1146 PM CST Sun Jan 01 2023

   Valid 021200Z - 031200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR THE
   ARKLATEX VICINITY INTO THE MID-SOUTH...

   ...SUMMARY...
   Severe thunderstorms are expected Monday and Monday night from
   eastern Oklahoma and Texas into Louisiana/Arkansas and vicinity.
   Tornadoes and scattered damaging winds will be the main hazards with
   these storms. Some of the tornadoes could be strong.

   ...South-central States...
   A strong upper-level trough within the Four Corners will eject into
   the southern High Plains and rapidly become negatively tilted as it
   pivots into the central Plains through Tuesday morning. A surface
   low initially within the Colorado Plateau will redevelop to the
   east/northeast into the mid-Mississippi Valley region. Strong
   moisture advection is expected to occur overnight Sunday into Monday
   ahead of the surface low. Current surface observations show
   mid/upper 60s F dewpoints are already as far north as northern
   Louisiana. Storms could develop this afternoon within the warm
   advection regime as well as along the advancing cold front.

   A somewhat complicated convective scenario is expected to unfold. A
   capping inversion evident on this evenings observed soundings should
   limit convection early in the day. The largest source of uncertainty
   is the potential for storms to form within a warm advection zone
   from the ArkLaTex into parts of the southern Ozarks. These early
   storms would still be capable of all severe hazards, but scattered
   to numerous storms could end up interfering with one another and
   impacting the environment for storms that would be expected later in
   the afternoon.

   Higher confidence exists in storms developing along the Pacific
   front and near the surface low from eastern Oklahoma into southeast
   Kansas and southwest Missouri. Observed soundings upstream of these
   locations sampled lapse rates of 7.5-8 C/km. Strong shear profiles
   with long, straight hodographs will favor potential for large hail
   early in the convective cycle. Given the forcing, it is unclear how
   long storms will remain discrete, but isolated very large hail would
   be possible with sustained supercells.

   With the low-level jet increasing during the day, potential for
   tornadoes will exist with initial supercells and with circulations
   embedded within linear structures that will become more prevalent by
   evening into the overnight. Low-level shear will be strong enough to
   support some strong tornadoes. At present, the area of greatest
   concern for tornadoes appears to be from the ArkLaTex vicinity into
   central Arkansas. Should discrete storms form, they would move into
   an environment where low-level shear would be increasing with time.
   As alluded to, however, the potential for early warm advection
   storms to further limit boundary-layer destabilization keeps
   confidence too low for an increase in tornado probabilities in this
   region.

   As convection moves north and east with time, storms should grow
   upscale into one or more lines. 50-60 kt winds in the low levels
   will support potential for scattered damaging gusts, particularly in
   the Mid-South region. Guidance does show linear structures as far
   north as the lower Ohio River Valley, but cooler temperatures and
   more limited moisture will limit the severe threat with northward
   extent.

 

Edited January 2, 2023 by ClicheVortex2014

[ClicheVortex2014]

I'll be curious to see what they do with the day 2 outlook. Certainly a solid signal for warm sector convection. 1-2 mean STP (blue) extends pretty far north, too.

 

Edited January 2, 2023 by ClicheVortex2014

[snowlover2]

51 minutes ago, ClicheVortex2014 said:

I'll be curious to see what they do with the day 2 outlook. Certainly a solid signal for warm sector convection. 1-2 mean STP (blue) extends pretty far north, too.

 

Enhanced area added in the south.

Quote

 Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1243 AM CST Mon Jan 02 2023

   Valid 031200Z - 041200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
   SOUTHEAST LOUISIANA...SOUTHERN MISSISSIPPI AND SOUTHERN/CENTRAL
   ALABAMA...

   ...SUMMARY...
   Severe thunderstorms are possible from the Mid-South to the central
   Gulf Coast on Tuesday. Damaging gusts and a few tornadoes will be
   possible. The greatest severe-thunderstorm risk is expected from
   southeast Louisiana into southern Mississippi and southern/central
   Alabama, where strong gusts and a couple of strong tornadoes are
   possible.

   ...Mid-South to the Central Gulf Coast...

   A closed upper low over the central Plains and the attendant
   mid/upper shortwave trough will shift east toward the mid/upper MS
   Valley/Great Lakes vicinity on Tuesday. This system will be
   contained within a larger-scale upper trough slowly shifting east
   across the southern Rockies/southern Plains. Strong deep-layer
   southwesterly flow will persist from TX into the OH Valley. 

   Morning convection is expected to be ongoing ahead of a cold front
   from the Lower OH Valley into northern MS and continuing southwest
   into southeast TX. Stronger and more progressive larger-scale ascent
   will be focused over northern portions of the area during the
   morning. Upper 50s to low 60s F boundary-layer dewpoints will
   contribute to weak instability amid strong shear. As a result, some
   of this activity may be strong to severe (mainly wind) from portions
   of KY/TN into the northern MS vicinity. Further south into northern
   LA and southeast TX, more cellular convection is possible during the
   first few hours of the period, but large-scale ascent will be rather
   weak across this area, and a minimum in storm intensity may persist
   through morning.

   Ahead of the large-scale upper trough, a lead shortwave impulse,
   within a sub-tropical jet streak oriented from the western Gulf of
   Mexico into the central Gulf Coast states, may be a focus for severe
   thunderstorm develop by afternoon across southeast LA into parts of
   MS/AL. Height falls across the area will remain modest until
   overnight. However, strong vertical shear will overlap mid/upper 60s
   F boundary-layer dewpoints (perhaps near 70 F south of I-20).
   Forecast soundings show wind profiles favorable for supercells amid
   1000-1500 J/kg MLCAPE. Most CAMs indicate supercell development
   ahead of the main line of convection associated with the
   eastward-percolating cold front, and in the vicinity of a marine
   warm front. While some uncertainty still exists in timing and
   coverage, discrete supercells may produce a few tornadoes (some
   possibly strong).

   Additional convection is expected along the surface cold front,
   which will creep east/southeast through the period, becoming
   oriented from central KY/Middle TN to far southeast LA by Wednesday
   morning. Severe potential with overnight activity remains uncertain
   and depends on how convection evolves during the day, and how much
   airmass recovery can occur. Nevertheless, it appears possible some
   areas may see more than one round of severe storms on Tuesday.

   ..Leitman.. 01/02/2023

 

 

[ElectricStorm]

First slight risk in NE OK in Jan since 2020, hopefully we can cash it in 

Also the 12z HRRR is looking way more discrete for us, wonder if they'll move that 5% north 

Edited January 2, 2023 by OKwx_2001

[Iceresistance]

It looks like that the Enhanced and Slight risk will shift west towards me because the Supercells could be much more discrete here in Central Oklahoma compared to Louisiana and Arkansas. 

[Iceresistance]

I just looked at the dew point temperatures, it's 60°F outside. Which is INSANE for January standards. 

[Ingyball]

Been on mids so I haven't been active the last few days. Gonna head to bed soon but these latest HRRR runs are getting quite interesting here.

 

[Ingyball]

Not absurdly impressive, but still something.