March 29-31, 2022 | Severe Weather, a second outbreak with more than 70 Tornadoes confirmed

[ClicheVortex2014]

I.... was not expecting this

Big moderate risk for tornadoes... hatched 10% tornado covers all of Mississippi and most of Alabama and Louisiana. Very big moderate risk for damaging winds.

Interestingly, SPC expects linear storm mode to dominate with little threat for pre-squall supercells. But that speaks to their thoughts about the embedded supercells/mesovortices they're expecting.

DAY 2 CONVECTIVE OUTLOOK    
NWS STORM PREDICTION CENTER NORMAN OK  
1254 AM CDT TUE MAR 29 2022  
  
VALID 301200Z - 311200Z  
  
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS  
OF LOUISIANA...MISSISSIPPI...AND ALABAMA...  
   
..SUMMARY  
  
A REGIONAL OUTBREAK OF SEVERE THUNDERSTORMS IS EXPECTED ON WEDNESDAY  
ACROSS THE LOWER MISSISSIPPI VALLEY AND SOUTHEAST STATES. ALL SEVERE  
HAZARDS ARE POSSIBLE, INCLUDING SIGNIFICANT GUSTS OVER 75 MPH AND  
STRONG (EF2+) TORNADOES.  
  
...SEVERE-WEATHER OUTBREAK POSSIBLE ACROSS PORTIONS OF  
LOUISIANA...MISSISSIPPI...AND ALABAMA...  
   
..SYNOPSIS  
  
A STRONG SOUTHERN-STREAM SHORTWAVE TROUGH IS FORECAST TO EXTEND FROM  
CENTRAL KS THROUGH THE TX HILL COUNTRY EARLY WEDNESDAY MORNING. THIS  
SHORTWAVE IS EXPECTED TO PROGRESS EASTWARD/NORTHEASTWARD THROUGHOUT  
THE DAY, BECOMING INCREASINGLY NEGATIVELY TILTED AS IT DOES. STRONG  
MID-LEVEL FLOW WILL ACCOMPANY THIS THROUGH, WITH 100+ KT AT 500 MB  
STRETCHING FROM SOUTHEAST TX NORTHEASTWARD THROUGH THE MID-SOUTH  
WEDNESDAY AFTERNOON. ADDITIONALLY, VERY STRONG LOW-LEVEL FLOW WILL  
PRECEDE THIS FEATURE, WITH A LARGE AREA OF 60+ KT AT 850 MB EXPECTED  
ACROSS THE MS VALLEY WEDNESDAY AFTERNOON.  
  
LOW-LEVEL MOISTURE ADVECTION WILL ALSO PRECEDE THIS SHORTWAVE  
TROUGH, BRINGING AT LEAST LOW 60S DEWPOINTS THROUGH THE MID-SOUTH/TN  
VALLEY. UPPER 50S DEWPOINTS WILL LIKELY REACH INTO THE LOWER/MIDDLE  
OH VALLEY. THESE DEWPOINTS WILL HELP FOSTER AT LEAST MODEST BUOYANCY  
AND THUNDERSTORMS ARE ANTICIPATED AS THE SHORTWAVE EJECTS  
NORTHEASTWARD OVER THIS MOIST AND BUOYANT AIRMASS. GIVEN THE  
STRENGTH OF THE WIND FIELDS, SEVERE THUNDERSTORMS ARE LIKELY,  
PARTICULARLY ACROSS PORTIONS OF THE LOWER MS VALLEY AND SOUTHEAST  
WHERE A REGIONAL OUTBREAK OF SEVERE THUNDERSTORMS IS ANTICIPATED.  
   
..LOWER MS VALLEY INTO THE TN VALLEY AND SOUTHEAST  
  
A LINE OF THUNDERSTORMS WILL LIKELY BE ONGOING FROM THE OZARK  
PLATEAU SOUTHWESTWARD INTO EAST TX EARLY WEDNESDAY. EXPECTATION IS  
FOR THIS LINE OF STORMS TO QUICKLY MOVE EASTWARD, OUTPACING A COLD  
FRONT MOVING SOUTHEASTWARD INTO THE MS VALLEY. WIDESPREAD CLOUDS  
WILL LIMIT DIURNAL HEATING DOWNSTREAM OF THIS LINE OF STORMS, BUT  
STRONG MOISTURE ADVECTION WILL STILL RESULT IN AT LEAST MODEST  
BUOYANCY AND AIRMASS DESTABILIZATION. AT THE SAME TIME, WIND FIELDS  
WILL STRENGTHEN CONSIDERABLY. THIS COMBINATION OF BUOYANCY AND VERY  
STRONG WIND SHEAR IS FORECAST TO RESULT IN A STRENGTHENING OF THE  
LINE AS IT MOVES INTO EASTERN AR AND LA DURING THE EARLY AFTERNOON,  
BEFORE THEN CONTINUING QUICKLY EASTWARD ACROSS MS AND AL DURING THE  
EVENING AND OVERNIGHT.  
  
THE KINEMATIC FIELDS, ESPECIALLY IN THE LOW-LEVELS AROUND 850 TO 700  
MB, ARE FORECAST TO BE VERY INTENSE. MEAN WIND SPEEDS FROM THE HREF  
SHOW A CORRIDOR OF 70 KT AT 850 MB FROM CENTRAL LA INTO SOUTHEAST AR  
AT 18Z. DEEP-LAYER MEAN WINDS ARE FORECAST TO BE 65+ KT ACROSS MUCH  
OF LA, MS, AND AL AS THE LINE MOVES THROUGH. EXPECTATION IS THAT  
THESE ROBUST WIND FIELDS WILL RESULT IN AN INTENSE CONVECTIVE LINE  
CAPABLE OF WIDESPREAD WIND DAMAGE. EMBEDDED/QLCS TORNADOES ARE ALSO  
LIKELY WITHIN THIS ENVIRONMENT, INCLUDING THE POTENTIAL FOR STRONG  
TORNADOES (EF2+).  FAST STORM MOTION COULD RESULT IN LONGER-TRACK  
QLCS TORNADOES THAN ARE TYPICALLY OBSERVED.  
  
IN ADDITION TO THE STRONG WIND GUSTS AND EMBEDDED QLCS TORNADOES,  
DISCRETE SUPERCELLS AHEAD OF AND/OR SOUTH OF THE PRIMARY CONVECTIVE  
LINE ARE ALSO POSSIBLE. ANY DISCRETE STORM THAT IS ABLE TO MATURE  
AND DEEPEN WOULD LIKELY BECOME AN INTENSE SUPERCELL CAPABLE OF  
PRODUCING SEVERE WIND GUSTS AND STRONG TORNADOES. HOWEVER, THE  
FORCING FOR ASCENT AND FAST-MOVING CHARACTER OF THE SHORTWAVE (AS  
WELL AS THE CONVECTIVE LINE) DO NOT FAVOR A DISCRETE CONVECTIVE  
MODE, AND THE CURRENT EXPECTATION IS FOR THE LINEAR MODE TO  
DOMINATE.  
   
.MID MS AND LOWER/MID OH VALLEYS  
   
LESS LOW-LEVEL MOISTURE AND BUOYANCY IS ANTICIPATED IN THE REGION  
COMPARED TO FARTHER SOUTH. HOWEVER, STRONG FORCING FOR ASCENT SHOULD  
HELP MAINTAIN THE CONVECTIVE LINE AS IT MOVES EASTWARD THROUGH THE  
REGION. STRONG WIND FIELDS SUPPORT THE POTENTIAL FOR DAMAGING WIND  
GUSTS WITH ANY DEEP CONVECTION, EVEN IN AREAS THAT EXHIBIT SHALLOW  
LOW-LEVEL STABILITY.  

e

Edited March 29, 2022 by ClicheVortex2014

[snowlover2]

Quote

 Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1254 AM CDT Tue Mar 29 2022

   Valid 301200Z - 311200Z

   ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
   OF LOUISIANA...MISSISSIPPI...AND ALABAMA...

   ...SUMMARY...
   A regional outbreak of severe thunderstorms is expected on Wednesday
   across the Lower Mississippi Valley and Southeast States. All severe
   hazards are possible, including significant gusts over 75 mph and
   strong (EF2+) tornadoes.

   ...SEVERE-WEATHER OUTBREAK POSSIBLE ACROSS PORTIONS OF
   LOUISIANA...MISSISSIPPI...AND ALABAMA...

   ...Synopsis...
   A strong southern-stream shortwave trough is forecast to extend from
   central KS through the TX Hill Country early Wednesday morning. This
   shortwave is expected to progress eastward/northeastward throughout
   the day, becoming increasingly negatively tilted as it does. Strong
   mid-level flow will accompany this through, with 100+ kt at 500 mb
   stretching from southeast TX northeastward through the Mid-South
   Wednesday afternoon. Additionally, very strong low-level flow will
   precede this feature, with a large area of 60+ kt at 850 mb expected
   across the MS Valley Wednesday afternoon.

   Low-level moisture advection will also precede this shortwave
   trough, bringing at least low 60s dewpoints through the Mid-South/TN
   Valley. Upper 50s dewpoints will likely reach into the Lower/Middle
   OH Valley. These dewpoints will help foster at least modest buoyancy
   and thunderstorms are anticipated as the shortwave ejects
   northeastward over this moist and buoyant airmass. Given the
   strength of the wind fields, severe thunderstorms are likely,
   particularly across portions of the Lower MS Valley and Southeast
   where a regional outbreak of severe thunderstorms is anticipated.

   ...Lower MS Valley into the TN Valley and Southeast...
   A line of thunderstorms will likely be ongoing from the Ozark
   Plateau southwestward into East TX early Wednesday. Expectation is
   for this line of storms to quickly move eastward, outpacing a cold
   front moving southeastward into the MS Valley. Widespread clouds
   will limit diurnal heating downstream of this line of storms, but
   strong moisture advection will still result in at least modest
   buoyancy and airmass destabilization. At the same time, wind fields
   will strengthen considerably. This combination of buoyancy and very
   strong wind shear is forecast to result in a strengthening of the
   line as it moves into eastern AR and LA during the early afternoon,
   before then continuing quickly eastward across MS and AL during the
   evening and overnight.

   The kinematic fields, especially in the low-levels around 850 to 700
   mb, are forecast to be very intense. Mean wind speeds from the HREF
   show a corridor of 70 kt at 850 mb from central LA into southeast AR
   at 18Z. Deep-layer mean winds are forecast to be 65+ kt across much
   of LA, MS, and AL as the line moves through. Expectation is that
   these robust wind fields will result in an intense convective line
   capable of widespread wind damage. Embedded/QLCS tornadoes are also
   likely within this environment, including the potential for strong
   tornadoes (EF2+).  Fast storm motion could result in longer-track
   QLCS tornadoes than are typically observed.

   In addition to the strong wind gusts and embedded QLCS tornadoes,
   discrete supercells ahead of and/or south of the primary convective
   line are also possible. Any discrete storm that is able to mature
   and deepen would likely become an intense supercell capable of
   producing severe wind gusts and strong tornadoes. However, the
   forcing for ascent and fast-moving character of the shortwave (as
   well as the convective line) do not favor a discrete convective
   mode, and the current expectation is for the linear mode to
   dominate.

   ..Mid MS and Lower/Mid OH Valleys... 
   Less low-level moisture and buoyancy is anticipated in the region
   compared to farther south. However, strong forcing for ascent should
   help maintain the convective line as it moves eastward through the
   region. Strong wind fields support the potential for damaging wind
   gusts with any deep convection, even in areas that exhibit shallow
   low-level stability.

   ..Mosier.. 03/29/2022

 

 

[Ingyball]

We're probably going to need a high risk for winds with this system. NAEFS is suggesting 60-70kt 850mb winds in the moderate area, it won't be hard to mix those down to the surface with convection. Would not be surprised if we saw some 100mph+ wind reports with this system. 

[ElectricStorm]

1 hour ago, Ingyball said:

We're probably going to need a high risk for winds with this system. NAEFS is suggesting 60-70kt 850mb winds in the moderate area, it won't be hard to mix those down to the surface with convection. Would not be surprised if we saw some 100mph+ wind reports with this system. 

Yeah that's definitely possible. It's been awhile since we've seen a 60 hatched for wind.

I'm surprised they went with a big 15 hatched tor risk. That's a lot of confidence for what should be a mostly linear system. 

[Iceresistance]

1 hour ago, OKwx_2001 said:

Yeah that's definitely possible. It's been awhile since we've seen a 60 hatched for wind.

I'm surprised they went with a big 15 hatched tor risk. That's a lot of confidence for what should be a mostly linear system. 

Maybe because of a higher-than-normal threat of QLCS tornadoes within the Squall Line

[Bman10]

Reminding me a bit of the December 15 derecho. All those embedded QLCS tornados . Maybe that’s what SPC is thinking too 

[Cincysnow]

Wind headlines are being hoisted

[ElectricStorm]

I think we're going to have to watch E AL tomorrow for pre squall cells. Any of those that can remain discrete enough could produce strong tornadoes along with the squall itself. 

[snowlover2]

Updated day 1 expands the slight risk north to extreme SW MN and expands the 5% tornado area to E KS/W MO. Wondering what kind of effect this might have for the day 2 update.

Quote

 Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1124 AM CDT Tue Mar 29 2022

   Valid 291630Z - 301200Z

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING AND
   TONIGHT FROM THE LOWER MISSOURI VALLEY INTO CENTRAL TEXAS...

   ...SUMMARY...
   Severe thunderstorms are expected this evening and tonight, from the
   lower Missouri Valley region to central Texas.  Damaging gusts, hail
   and a few tornadoes are possible.

   A deep upper low over western AZ is tracking eastward across the
   southern Rockies today, with the primary upper jet max forecast to
   rotate through the base of the trough and across much of the
   southern Plains tonight.  As this occurs, three different regimes of
   strong/severe convection are expected.

   ...Eastern NE/Western IA...
   The main surface low is forecast to deepen as it moves into
   east-central NE by early evening.  Southeasterly low-level winds
   will help transport a narrow corridor of 50s dewpoints and
   surface-based instability into parts of eastern NE and western IA,
   where CAM guidance is in agreement that scattered thunderstorms will
   form.  These storms will only briefly be surface-based before they
   track northward across the warm front into a cooler/stable
   boundary-layer.  There is a chance of a brief tornado or two before
   the storms become elevated, after which the main threat will be hail
   and gusty winds. 

   ...Eastern KS/Western MO/Southern IA...
   A surface dryline is expected to become established later today from
   western OK into central KS.  Temperatures in the 80s and dewpoints
   rising into the mid/upper 50s along the boundary will help to weaken
   the cap and lead to scattered thunderstorms - mainly after 23z. 
   This activity should persist through the evening as cooling aloft
   and the primary cold front move into the region.  Initial storms may
   be supercellular with all severe hazards possible.  A gradual
   evolution to a QLCS is expected by mid-evening with damaging winds
   and isolated mesovortex spin-ups being the main threats.

   ...Southern OK into West-central TX...
   Surface temperatures over 90F are expected just west of the dryline
   over southwest OK and west-central TX this afternoon, resulting in a
   narrow corridor of weak cap.  A few thunderstorms may form in this
   area, capable of large hail and damaging winds.  Forecast soundings
   show a formidable cap is present as storms evolve off the dryline
   and into the warm sector.  Increasing large-scale forcing will
   arrive after dark, helping to weaken the cap and foster more
   widespread convection.  However, linear convective modes are likely
   by that time with locally damaging wind gusts the main threat.

   ..Hart/Wendt.. 03/29/2022

 

 

[TLChip]

HRRR putting out some high values 

 

Edited March 29, 2022 by TLChip

[snowlover2]

Quote

DAY 2 CONVECTIVE OUTLOOK    
NWS STORM PREDICTION CENTER NORMAN OK  
1230 PM CDT TUE MAR 29 2022  
  
VALID 301200Z - 311200Z  
  
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
LOUISIANA...EASTERN ARKANSAS...MISSISSIPPI...WESTERN  
TENNESSEE...ALABAMA...AND THE WESTERN FLORIDA PANHANDLE...  
   
..SUMMARY  
  
A REGIONAL OUTBREAK OF SEVERE THUNDERSTORMS IS EXPECTED ON WEDNESDAY  
ACROSS THE LOWER MISSISSIPPI VALLEY AND SOUTHEAST. ALL SEVERE  
HAZARDS ARE POSSIBLE, INCLUDING WIDESPREAD DAMAGING WINDS, SOME OVER  
75 MPH, AND SEVERAL TORNADOES, SOME OF WHICH COULD BE STRONG (EF2+).  
   
..SYNOPSIS  
  
A SHORTWAVE TROUGH WILL EJECT FROM THE SOUTHERN PLAINS ACROSS THE  
LOWER/MID MS VALLEY ON WEDNESDAY WHILE ACQUIRING A NEGATIVE TILT. AN  
80-100+ KT SOUTH-SOUTHWESTERLY MID-LEVEL JET WILL ACCOMPANY THE  
SHORTWAVE TROUGH PASSAGE. LOW-LEVEL SOUTHERLY FLOW IS ALSO EXPECTED  
TO BE VERY STRONG, WITH 50-70+ KT WINDS FORECAST AT 850 MB. THE  
PRIMARY SURFACE LOW SHOULD BE LOCATED OVER IA AT THE START OF THE  
PERIOD, WITH A COLD FRONT EXTENDING SOUTHWARD FROM THIS LOW ACROSS  
THE CENTRAL/SOUTHERN PLAINS. A SECONDARY SURFACE LOW IN CLOSER  
PROXIMITY TO THE SHORTWAVE TROUGH IS FORECAST TO DEVELOP FROM  
EASTERN OK TO THE MID-SOUTH VICINITY BY WEDNESDAY EVENING.  
  
AT LEAST LOW TO MID 60S SURFACE DEWPOINTS ARE EXPECTED TO RETURN  
NORTHWARD ACROSS THE LOWER MS VALLEY AND SOUTHEAST AHEAD OF THE  
SECONDARY SURFACE LOW, WITH THE SURFACE WARM SECTOR BECOMING  
INCREASINGLY PINCHED OFF WITH NORTHWARD EXTENT INTO THE MID MS AND  
OH VALLEYS. WITH STRONG FORCING FOR ASCENT ASSOCIATED WITH THE  
SHORTWAVE TROUGH OVERSPREADING THE WARM SECTOR THROUGH THE DAY,  
THUNDERSTORMS WILL DEVELOP AND MOVE EAST-NORTHEASTWARD AHEAD OF THE  
COLD FRONT WHILE POSING A THREAT FOR BOTH WIDESPREAD DAMAGING WINDS  
AND SEVERAL TORNADOES.  
   
..LOWER MISSISSIPPI VALLEY INTO THE SOUTHEAST  
  
A LINE OF CONVECTION AIDED BY STRONG LOW-LEVEL WARM ADVECTION WILL  
LIKELY BE ONGOING AT THE START OF THE PERIOD FROM THE OZARKS  
SOUTHWARD ACROSS AR TO EAST TX. THIS ACTIVITY SHOULD CONTINUE TO  
POSE A THREAT FOR AT LEAST ISOLATED DAMAGING WINDS AND TORNADOES AS  
IT MOVES EASTWARD WEDNESDAY MORNING. FAIRLY WIDESPREAD CLOUD COVER  
AHEAD OF THE LINE AND MODEST MID-LEVEL LAPSE RATES SHOULD TEMPER THE  
DEGREE OF DESTABILIZATION TO SOME EXTENT. STILL, THE INCREASING  
LOW-LEVEL MOISTURE IN TANDEM WITH FILTERED DIURNAL HEATING ARE  
EXPECTED TO AID IN SUFFICIENT BOUNDARY-LAYER DESTABILIZATION TO  
SUPPORT SURFACE-BASED STORMS. MLCAPE AROUND 500-1000 J/KG SHOULD  
DEVELOP AHEAD OF THE LINE ACROSS LA INTO MS AND SURROUNDING AREAS BY  
EARLY WEDNESDAY AFTERNOON.  
  
THIS QLCS SHOULD STRENGTHEN WEDNESDAY AFTERNOON AS IT MOVES ACROSS  
NORTHEASTERN LA, EASTERN AR, SOUTHEASTERN MO, AND INTO MUCH OF THE  
LOWER MS VALLEY AND MID-SOUTH. AIDED BY STRENGTHENING LOW/MID-LEVEL  
FLOW, INCREASING LOW-LEVEL AND DEEP-LAYER SHEAR WILL BOTH BECOME  
VERY STRONG, SUPPORTING UPDRAFT ORGANIZATION. WITH A PRIMARILY  
LINEAR STORM MODE EXPECTED, WIDESPREAD SEVERE/DAMAGING WINDS APPEAR  
LIKELY. THE PRESENCE OF A 50-70+ KT SOUTH-SOUTHWESTERLY LOW-LEVEL  
JET, AND EVEN STRONGER FLOW UP TO 75 KT AT 700 MB, SHOULD ENHANCE  
THE PROSPECTS FOR SIGNIFICANT SEVERE WIND GUSTS OF 75+ MPH AT THE  
SURFACE WITHIN THE MOST INTENSE PORTIONS OF THE LINE WEDNESDAY  
AFTERNOON AND EVENING. VERY FAVORABLE LOW-LEVEL SHEAR AND  
ELONGATED/SICKLE-SHAPED HODOGRAPHS IN THE BOUNDARY LAYER WILL LIKELY  
ALSO SUPPORT LOW-LEVEL ROTATION WITH EMBEDDED MESOVORTICIES WITHIN  
THE QLCS. SEVERAL TORNADOES SHOULD OCCUR ACROSS THE LOWER MS VALLEY  
AND SOUTHEAST IN THIS REGIME, WITH CIRCULATIONS MOVING QUICKLY  
EAST-NORTHEASTWARD.  
  
THE POTENTIAL FOR SUPERCELLS TO DEVELOP AHEAD OF THE LINE, OR  
PERHAPS EMBEDDED WITHIN THE LINE WITH SOUTHWARD EXTENT, REMAINS  
UNCLEAR. ANY CELLS THAT CAN FORM AHEAD OF THE LINE WOULD BE FAVORED  
TO PRODUCE TORNADOES, BUT THE QUICK EASTWARD PROGRESSION OF THE QCLS  
MAY LIMIT THIS POSSIBILITY. STILL, SOME GUIDANCE SUGGESTS THE  
SOUTHERN PART OF THE LINE MAY BECOME MORE BROKEN WITH TIME WEDNESDAY  
AFTERNOON/EVENING. IF THIS OCCURS, THEN A THREAT FOR EMBEDDED  
SUPERCELLS CAPABLE OF PRODUCING MULTIPLE STRONG (EF2+) TORNADOES  
WOULD EXIST. AT THIS POINT, THE GREATEST TORNADO POTENTIAL MAY FOCUS  
ALONG SOUTHERN PORTIONS OF THE LINE IN MS/AL WHERE A SEMI-DISCRETE  
MODE SEEMS MORE PLAUSIBLE. REGARDLESS, A CONTINUED THREAT FOR BOTH  
DAMAGING WINDS AND TORNADOES WILL LIKELY PERSIST WEDNESDAY EVENING  
AND OVERNIGHT AS CONVECTION SPREADS FROM THE LOWER MS VALLEY INTO  
THE TN VALLEY AND DEEP SOUTH. THUNDERSTORMS SHOULD EVENTUALLY WEAKEN  
WITH EASTWARD EXTENT EARLY THURSDAY MORNING AS THEY OUTPACE THE  
LOW-LEVEL MOISTURE RETURN AND ENCOUNTER A LESS FAVORABLE  
THERMODYNAMIC ENVIRONMENT.  
   
..MID MISSISSIPPI VALLEY INTO THE OHIO VALLEY  
  
LESS LOW-LEVEL MOISTURE AND WEAKER INSTABILITY ARE FORECAST ACROSS  
THE MID MS VALLEY AND OH VALLEY COMPARED TO LOCATIONS FARTHER SOUTH.  
HOWEVER, ENOUGH BOUNDARY-LAYER INSTABILITY SHOULD BE PRESENT FOR THE  
LINE OF STORMS TO PRODUCE SCATTERED TO PERHAPS NUMEROUS DAMAGING  
WINDS AS IT MOVES EASTWARD GIVEN THE STRENGTH OF THE LOW-LEVEL FLOW.  
A FEW TORNADOES MAY ALSO OCCUR WITH FAVORABLE LOW-LEVEL SHEAR ALSO  
PRESENT. THE LACK OF STRONGER INSTABILITY PRECLUDES GREATER SEVERE  
PROBABILITIES ACROSS THIS REGION AT THIS TIME.  
  
..GLEASON.. 03/29/2022 

 

 

 

Edited March 29, 2022 by snowlover2

[ElectricStorm]

Huge 45 hatched wind area 

[ClicheVortex2014]

Very bad situation for Jackson... needless to say. But what's worse is they're considering high wind watches/warnings for the warm sector. Before the squall even comes. Talking about power outages before the widespread damaging winds/qlcs tornado outbreak. They do seem to disagree with SPC regarding the latter. 

A closed low system off the Pacific will open into an elongated
trough that will push across the region Wedneuppersday. At the
same time a closed surface low negatively tilted will eject across
the northern Plains into the Great Lakes region. What does this
mean for our area across the Deep South... well as this trough
pushes across the ArkLaMiss, there will be a very tight pressure
gradient. As we begin to mix out and reach peak heating (upper 70s
to mid 80s), winds will have the chance to gust to some 50-70 mph
and even higher in more localized areas that are naturally
warmer. Soundings across the region show inverted V signals which
typically is a good indicator of high winds being transferred to
the surface and CAM models show mixing down to about the 850mb
level. With that, will continue the `Significant Risk` for winds
on Wednesday and issue a `Wind Advisory` for the entire area
starting 9AM Wednesday through 7PM. There has been talk of maybe
issuing a high wind watch/warning across the west for a limited
amount of time on Wednesday however criteria will be just below
but with this set up, it may be something considered for later
forecast packages. Downed trees and powerlines are likely and
driving conditions will be hazardous especially for high profile
vehicles.

An associated cold front will also serve as a main factor for severe
weather. Ahead of the front temperatures will warm into the 80s for
most places. Warm air from the Gulf will increase moisture across
the Deep South. With this high shear (40-50 kts 0-3km) and low CAPE
(up to 1100 j/Kg) environment, discrete cells ahead of this line
is not likely and storm mode will likely be linear (QLCS). With
high LCL`s (1200m) and alot of wind energy, sig tornadoes are not
the primary concern however as I stated earlier, embedded
tornadoes within the QLCS will still be possible. With the threat
increasing for high winds SPC has upgraded our area to a `Moderate
Risk`. As far as timing, the line will be entering the western
part of our region around or just before noon and will progress
east. Areas across central and east MS can expect the line around
2-3PM and lasting through 8PM.

 

Edited March 29, 2022 by ClicheVortex2014

[ClicheVortex2014]

18z HRRR

[Iceresistance]

@Ingyball

15z SREF has a 60% STP just south of Wichita, KS

[snowlover2]

ILN

Quote

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
A busy 24 period of weather with concerns for fire weather /see
discussion below/, strong winds, severe storms, and anomalous
warmth.

Vigorous shortwave trough will deepen and become negatively
tilted during the day into the evening to our northwest across
Minnesota/Wisconsin. Initial sub-990mb surface cyclone over Iowa
on Wednesday morning will drift slowly eastward into Illinois
Wednesday afternoon, before accelerating and deepening more
quickly Wednesday night as the trough becomes negatively tilted.
MSLP likely to drop to around 977mb or so as the cyclone drifts
across northern lower Michigan on Wednesday night.

Main impacts from this dynamic/potent low pressure will be 1)
maintenance and further development of gradient winds and an
intense low level jet across the area Wednesday afternoon and
night 2) QLCS weakening as it enters the forecast area Wednesday
evening and 3) very warm temperatures with highs in the
mid/upper 70s.

Regarding the winds - forecast soundings indicate that initially
very dry sub-cloud layers will warm efficiently and allow some
portions of the low level jet across the Ohio Valley to begin
mixing to the surface. Especially after about 1 PM, winds/gusts
should steadily increase with steeper low level lapse rates and
warming temperatures despite a fair amount of clouds. CIPS
analogs to the pattern in place Wednesday evening suggests good
chances of wind gusts> 40 kts across Ohio/Indiana, and certainly
fits the pattern of a sub-980mb surface low crossing WI/MI.
These winds will not abate after sunset, and in fact, with the
trough becoming negatively tilted and the surface low deepening
more steadily Wednesday night, expect wind potential may
increase a bit after sunset, especially ahead of weakening QLCS
as it plows into the drier air and perhaps is enhanced by
isallobaric/evaporative cooling effects. Am somewhat concerned
that CAM solutions amp up the winds while ramping down the
simulated reflectivity, indicating perhaps some favorable
downdraft/evap cooling mechanisms may be in play as the
weakening convective system moves in. Would not be surprised if
there was a need for a few SVR thunderstorm warnings across the
southwest third of the CWA despite what appears to be very
little chance for charge separation /lightning/. Instability is
very meager if not nil, but SHERB parameters suggest low/mid
level lapse rates will be substantial enough to allow wind
damage anyway. Will watch this closely, and think SPC MRGL risk
is well placed and appropriate. Wind Advisory much of the
forecast area, may need to be expanded to all of the forecast
area in future forecasts, but wanted to hit the higher
confidence areas first which is eastern Indiana/western
Ohio/northern Kentucky.

Should see rain chances taper off quickly after about 2 AM, but
actual cold front will just be entering the forecast area in the
the hours before sunrise, and this feature may offer some gusty
low-topped showers of its own to contend with, although low
level moisture will have begun to scour out by then.

 

 

[ClicheVortex2014]

   Mesoscale Discussion 0338
   NWS Storm Prediction Center Norman OK
   0310 PM CDT Tue Mar 29 2022

   Areas affected...portions of northwest and north-central OK into
   central KS and far southeast NE

   Concerning...Severe potential...Watch likely 

   Valid 292010Z - 292215Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Thunderstorms are expected to develop across central
   Kansas and perhaps northwest or north-central OK by 23z. A watch
   will likely be needed for parts of this area in the next couple of
   hours. Damaging wind gusts and hail are the main hazards expected
   with this activity, though a tornado or two also is possible.

   DISCUSSION...Cumulus continues to increase this afternoon behind the
   surface dryline from the OK/TX Panhandles/western OK into southwest
   KS, indicative of increasing ascent spreading eastward into the
   Plains. A surface low is positioned near Harlan County NE near the
   KS/NE border. A dryline extends south/southwest from the low across
   central KS into western OK. Strong capping is still evident east of
   the dryline in latest mesoanalysis data and in cloud presentation in
   visible satellite. 18z RAOB from OUN also continues to show a stout
   capping inversion around 850-700 mb. However, very steep midlevel
   lapse rates near 9 C/km were noted. Additionally, a modest but
   favorably curved low-level hodographs, becoming elongated above 3km
   was also present. 

   Southerly low-level flow will continue a warm advection regime ahead
   of the dryline and a broad area of 56-60 F surface dewpoints are in
   place across central/northern OK into south-central/southeast KS
   (diminishing with northward extent). As stronger ascent spreads
   eastward over the next few hours, high-based convection is expected
   to develop near the dryline from northwest OK into central KS.
   Convective coverage will likely increase more quickly across KS as
   the dryline is overtaken by a southeastward-surging cold front over
   western KS as of 1930z, before increasing later this evening further
   south across OK. Initial semi-discrete supercells are possible and
   may produce large hail and damaging gusts. Convection is expected to
   grow upscale rather quickly as the low-level jet strengthens this
   evening, bringing an attendant increase in damaging wind potential
   with eastward extent. While modest boundary-layer moisture will
   result in higher-based convection, low-level shear does support
   rotation and a tornado or two may be possible as well. A watch will
   likely be needed for portions of the MCD area by around 22z.

 

[ClicheVortex2014]

LCL is pretty high across the region but I'd imagine it'll lower as moisture continues to move in and daytime mixing ceases.

Edited March 29, 2022 by ClicheVortex2014

[ClicheVortex2014]

Another sign of how serious NWS is taking this event... much like last week, NWS offices are doing special balloon launches at 6z and 18z to help monitor the situation and help the models.

 

Little bit dry at ILN

Edited March 29, 2022 by ClicheVortex2014

[ClicheVortex2014]

And we have some cells west of Wichita. LCL is around 2500-3000 meters per mesoanalysis so I think a tornado threat can be ruled out for now.

Edited March 29, 2022 by ClicheVortex2014

[ElectricStorm]

Looks like @NebraskaEgg will finally get in on some of the action this time lol

[NebraskaEgg]

3 minutes ago, OKwx_2001 said:

Looks like @NebraskaEgg will finally get in on some of the action this time lol

Hopefully, it's been long enough. Wasn't in town for the December 15 event and before then, 2021 wasn't particularly active. Doesn't seem like today will be too big but it's better than the nothing we've been getting. The rain will help a lot too, been pretty dry here.

[ClicheVortex2014]

  Mesoscale Discussion 0340
   NWS Storm Prediction Center Norman OK
   0451 PM CDT Tue Mar 29 2022

   Areas affected...Western Oklahoma...Northwest/West-Central Texas

   Concerning...Severe potential...Severe Thunderstorm Watch likely 

   Valid 292151Z - 292315Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Scattered strong/severe thunderstorms are expected to
   initiate along the dryline. Wind/hail are the primary concerns.

   DISCUSSION...Strong boundary-layer heating has contributed to
   near-dry adiabatic lapse rate in the lowest 4km across west TX into
   western OK where surface temperatures have soared into the lower
   90s. Thickening cu field is currently noted along the eastern edge
   of this steep lapse-rate plume trailing to near I-20 north of BPG.
   Showers are gradually increasing across western OK and 700mb cooling
   is expected to remove remaining inhibition for deep, robust
   convection. Latest thinking is scattered strong/severe thunderstorms
   will develop along the dryline over the next few hours, initially
   high-based, but with time potentially becoming near-surface based as
   convection encounters increasingly moist low levels (~60F surface
   dew points). Strong mid-level height falls/forcing will contribute
   to an upward-evolving, broken squall line that will advance toward
   the I-35 corridor across OK late this evening, a bit later in
   north-central TX. Locally damaging winds and perhaps some hail are
   the primary concern.

[Ingyball]

Some nice storm structures outside. Just got home from work, stayed a couple of hours to assist with fire weather. Will probably go to sleep just as the storms arrive here since I'm back in at 6 AM again. 

[ClicheVortex2014]

Interesting probabilities for this watch. No middle ground regarding the threat. It's either high or low.