May 19-22 Severe Weather Threat

[Hoosier]

The time period draws closer and the signals appear to be robust/consistent enough to warrant a separate thread. A little early to hammer out specifics but given the instability/shear progs off of various models, would not be surprised if one or more of these days ends up with something higher than a slight risk in the region.

[andyhb]

The time period draws closer and the signals appear to be robust/consistent enough to warrant a separate thread. A little early to hammer out specifics but given the instability/shear progs off of various models, would not be surprised if one or more of these days ends up with something higher than a slight risk in the region.

 

I'd say Monday (despite the shading back of the D4, which looks to have been a bit premature based on the latest progs) likely holds the most significant potential for western parts of this sub-forum as the initial vort max responsible for the threat on Sunday rotates into the area. Tuesday and Wednesday hold potential too as the second s/w rotates around the base of the trough.

[wisconsinwx]

I'd say Monday (despite the shading back of the D4, which looks to have been a bit premature based on the latest progs) likely holds the most significant potential for western parts of this sub-forum as the initial vort max responsible for the threat on Sunday rotates into the area. Tuesday and Wednesday hold potential too as the second s/w rotates around the base of the trough.

 

Early on Dr. Greg Forbes has the highest TOR:CON, 5, projected for N Illinois that day.  I think surrounding areas are slightly lower, but I would think closer to the low (S and W Wisconsin, E Iowa) should have decent potential as well.

[YHM Supercell]

I'm curious as to how Tuesday may play out in the Southern Lakes. 12z GFS has 1500-2500j/kg of MUCAPE depending on your location with fairly favourable shear profiles for some damaging winds and probably some large hail as well. What is everyone else thinking? 

[Justin]

Only thing that would concern me for Eastern Iowa/Northern Illinois/Southern Wisconsin would be how the Sunday Night convection evolves, and how much of an Easterly component the wind comes off Lake Michigan which would likely reinforce any boundaries further South than what we are seeing.  I'm thinking the SPC was kind of going with the same thinking and thus shaded the outlook area for Monday back somewhat.  That of course will likely be adjusted much further, the threat for Monday, in the coming 24-48 hours.

[wisconsinwx]

Only thing that would concern me for Eastern Iowa/Northern Illinois/Southern Wisconsin would be how the Sunday Night convection evolves, and how much of an Easterly component the wind comes off Lake Michigan which would likely reinforce any boundaries further South than what we are seeing.  I'm thinking the SPC was kind of going with the same thinking and thus shaded the outlook area for Monday back somewhat.  That of course will likely be adjusted much further, the threat for Monday, in the coming 24-48 hours.

 

However, the general forecast is for southerly winds on Sunday and I believe Monday.  I certainly wouldn't be surprised if a lake breeze crops up on those days, but it seems it will be much less likely due to the moist S/SW flow.

[Justin]

If a bunch of storms or a huge complex forms in northern iowa and rolls into wisconsin sunday night that may reinforce some type of outflow boundary or the warm front further South. I'm not confident in that since, yes, strong Southerly winds should be blowing.

[cyclone77]

If a bunch of storms or a huge complex forms in northern iowa and rolls into wisconsin sunday night that may reinforce some type of outflow boundary or the warm front further South. I'm not confident in that since, yes, strong Southerly winds should be blowing.

 

Setup looks highly conditional on Monday for our area.  We've pretty much come to expect that though with these large-scale systems spawning outbreaks for days in the Plains before making it in here.  Leftover crapvection and associated clouds routinely keep the DVN area out of the strike zone with these kind of setups.  This setup looks very interesting though, and you never know how things will really evolve until the morning of, so it's definitely something to watch. 

[Geos]

Dewpoints really start taking off Sunday evening.

 

[frostfern]

This just might be a decent for a supercell/hail threat in my area Monday afternoon with a warm front in the area, morning sunshine, and SSE flow setting up a lake breeze.  High dewpoints and low LCLs too.  Reminds me of June 21 2011.  I have a feeling Tuesday will be cloudier with less instability but a stronger low level jet to mix down severe gusts.

[cyclone77]

Looks like the SREF sig tor ingredients have been bumped back to a more conservative output compared to the overblown sig tor after they changed it last year. 

 

This is for sun afternoon.  This would have been off the charts earlier this year and last year.

 

[Hoosier]

Looks like the SREF sig tor ingredients have been bumped back to a more conservative output compared to the overblown sig tor after they changed it last year.

This is for sun afternoon. This would have been off the charts earlier this year and last year.

Those thresholds look the same to me. It's just not that excited about significant tornadoes for whatever reason.

[Justin]

I think the situation Sunday Night bears a lot of watching... Monday could too reminds me of situations where one ingredient like shear may be great but instability is somewhat lacking...those can surprise. We'll see soon enough.

[RCNYILWX]

I think the situation Sunday Night bears a lot of watching... Monday could too reminds me of situations where one ingredient like shear may be great but instability is somewhat lacking...those can surprise. We'll see soon enough.

Agreed, the h5 ridging overhead during the day will keep things capped and really allow instability to build. Then it looks like a lead shortwave arrives during the evening and midlevel flow increases to as much as 40-50 kt between 0-6z, along with a strengthening LLJ. Areas near the Mississippi in IA and IL could have an interesting night.

Monday will depend on if potential morning convection and clouds clear out, because as you mentioned, deep layer shear won't be lacking. I haven't looked at the 00z NAM yet, but I thought the GFS and ECMWF looked better synoptically for the Monday threat in IA and IL than the earlier runs of the NAM. Particularly the Euro for nrn IL because it hinted at a secondary low over southern WI Monday PM that could keep surface winds more backed.

[huronicane]

00z NAM continues what has been shown the past few cycles...a wind profile not exactly classic for supercell tornadoes.  I still like how the GFS and Euro look from a purely chasing perspective, but I'll be glad to see any sort of active weather.

[PatrickSumner]

GFS looking pretty "interesting" for GL and OV Tuesday night/Wednesday.

[snowlover2]

New day 2 has the slight risk getting into the sub forum with a moderate risk just to the west.

 

DAY 2 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0100 AM CDT SAT MAY 18 2013
  
   VALID 191200Z - 201200Z
  
   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF ECNTRL OK...ERN
   KS AND WRN MO...
  
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE GREAT
   PLAINS AND LOWER TO MID MO VALLEY...
  
   ...REGIONAL SEVERE WEATHER OUTBREAK POSSIBLE ACROSS PARTS OF THE SRN
   PLAINS...CNTRL PLAINS AND LOWER MO VALLEY...
  
   ...SRN AND CNTRL PLAINS/LOWER MO VALLEY...
   A NEGATIVELY-TILTED UPPER-LEVEL TROUGH WILL MOVE EWD INTO THE SRN
   AND CNTRL PLAINS ON SUNDAY AS A MID-LEVEL JET MOVES EWD THROUGH THE
   CENTER OF THE TROUGH. AT THE SFC...A LOW IS FORECAST TO DEEPEN AND
   MOVE NEWD FROM CNTRL KS INTO ERN NEB AS A COLD FRONT ADVANCES SEWD
   ACROSS THE ECNTRL KS AND CNTRL OK. SFC DEWPOINTS TO THE EAST OF THE
   FRONT SHOULD BE IN THE MID TO UPPER 60S F WITH MODERATE TO STRONG
   DESTABILIZATION LIKELY ACROSS THE MODERATE RISK AREA BY MID TO LATE
   AFTERNOON. FORECAST SOUNDINGS AROUND MIDDAY SHOW A CAPPING INVERSION
   IN PLACE ACROSS MUCH OF THE WARM SECTOR. THE MODELS WEAKEN THE CAP
   BY 21Z ALLOWING FOR CONVECTIVE INITIATION ALONG AND AHEAD OF THE
   FRONT. STORMS SHOULD FIRST INITIATE IN NRN AND CNTRL KS...QUICKLY
   EXPANDING SWD INTO NRN AND CNTRL OK. AS STORM COVERAGE INCREASES
   DURING THE EARLY EVENING...A SEVERE PRODUCING MCS MAY ORGANIZE
   ACROSS ERN KS AND ECNTRL OK...MOVE ESEWD ACROSS THE MODERATE RISK
   AREA.
  
   FORECAST SOUNDINGS BY 21Z SUNDAY AT TULSA...OKLAHOMA CITY AND KANSAS
   CITY SHOW STRONG INSTABILITY WITH MLCAPE VALUES OF 2500 TO 3500
   J/KG. DEEP LAYER SHEAR IS FORECAST TO INCREASE DURING THE LATE
   AFTERNOON ACROSS THE MODERATE RISK AREA AS A MID-LEVEL JET MOVES
   INTO THE REGION FROM THE WEST. THIS COMBINED WITH 850 TO 500 MB
   LAPSE RATES EXCEEDING 8.0 C/KM SHOULD BE VERY FAVORABLE FOR
   SUPERCELLS WITH LARGE HAIL. HAILSTONES OF GREATER THAN 2 INCHES IN
   DIAMETER WILL BE POSSIBLE WITH THE MORE INTENSE SUPERCELLS. IN
   ADDITION...A LOW-LEVEL JET IS FORECAST TO BECOME FOCUSED BY EARLY
   SUNDAY EVENING FROM SW MO SWWD INTO ECNTRL OK. SUPERCELLS ON THE WRN
   EDGE OF THE LOW-LEVEL JET WILL HAVE A CHANCE TO BECOME TORNADIC WITH
   A CLUSTER OF TORNADOES POSSIBLE ACROSS THE MODERATE RISK AREA. THE
   GREATEST CHANCE FOR STRONG TORNADOES SHOULD EXIST ACROSS ECNTRL OK
   AND SE KS WHERE 0-3 KM STORM RELATIVE HELICITIES ARE FORECAST TO
   REACH 400 M2/S2 IN THE 00Z TO 03Z TIMEFRAME. DUE TO THE STRONG DEEP
   LAYER SHEAR...CELLS SHOULD REMAIN DISCRETE DURING MUCH OF THE EVENT.
   SUPERCELLS COULD ALSO PRODUCE SWATHS OF WIND DAMAGE. THE WIND DAMAGE
   THREAT COULD BECOME ENHANCED DURING THE EVENING IF A LINEAR MCS CAN
   ORGANIZE.
  
   ...MID-MO VALLEY/NRN PLAINS/UPPER MS VALLEY...
   SOUTH TO SOUTHWEST FLOW WILL BE IN PLACE ACROSS THE NCNTRL U.S.
   SUNDAY AS AN UPPER-LEVEL TROUGH MOVES INTO THE SRN AND CNTRL PLAINS.
   AT THE SFC...A LOW IS FORECAST TO DEEPEN AND MOVE NEWD INTO THE
   MID-MO VALLEY DURING THE DAY. A MODERATELY UNSTABLE AIRMASS SHOULD
   BE IN PLACE BY MID AFTERNOON TO THE EAST AND NORTHEAST OF THE LOW
   ACROSS ERN NEB...SERN SD...IA AND SRN MN WHERE SFC DEWPOINTS MAY
   REACH THE LOWER TO MID 60S F. THE AIRMASS SHOULD BE UNCAPPED ACROSS
   MUCH OF THE REGION ALLOWING FOR CONVECTIVE INITIATION TO TAKE PLACE
   EARLY IN THE DAY. THUNDERSTORMS COULD BE ONGOING DURING THE MORNING
   ACROSS IA AND MN ALONG WRN EDGE OF THE LOW-LEVEL JET WITH ADDITIONAL
   THUNDERSTORM DEVELOPMENT TAKING PLACE BENEATH THE UPPER-LEVEL LOW
   EARLY SUNDAY AFTERNOON. SEVERAL CLUSTERS OF ORGANIZED THUNDERSTORMS
   APPEAR LIKELY TO PERSIST THROUGH THE AFTERNOON WITH MCS DEVELOPMENT
   POSSIBLE ACROSS PARTS OF THE REGION BY EVENING.
  
   FORECAST SOUNDINGS AT OMAHA AND DES MOINES AT 21Z SHOW MODERATE
   INSTABILITY WITH MLCAPE VALUES IN THE 2000 TO 3000 J/KG RANGE. THIS
   COMBINED WITH 30 TO 40 KT OF 0-6 KM SHEAR SHOULD SUPPORT SUPERCELL
   DEVELOPMENT WITH A THREAT FOR LARGE HAIL. HAILSTONES OF GREATER THAN
   2 INCHES IN DIAMETER WILL BE POSSIBLE WITH THE MORE DOMINANT
   SUPERCELLS MAINLY IN SE NEB AND SRN IA WHERE INSTABILITY IS FORECAST
   TO BE THE GREATER THAN IN AREAS TO THE NORTH. A FEW TORNADOES MAY
   ALSO OCCUR WITH THE MORE INTENSE SUPERCELLS AS THE LOW-LEVEL JET
   STRENGTHENS EARLY SUNDAY EVENING. WIND DAMAGE WILL BE POSSIBLE WITH
   SUPERCELLS AND BOWING LINE-SEGMENTS ESPECIALLY IF AN MCS CAN
   ORGANIZE DURING THE EARLY EVENING.

 

 

[RCNYILWX]

Nice soundings for northern Illinois Monday evening:

 

00z NAM

 

00z GFS

 

Good midlevel lapse rates, good directional and speed shear up to the midlevels, though there is some back/veer above H5.

[Stebo]

Nice soundings for northern Illinois Monday evening:

 

00z NAM

 

00z GFS

 

Good midlevel lapse rates, good directional and speed shear up to the midlevels, though there is some back/veer above H5.

 

 

I'd say the back/veer above 500mb is pretty small especially on the NAM, still some spectacular soundings there with great MLCAPE.

[RCNYILWX]

I'd say the back/veer above 500mb is pretty small especially on the NAM, still some spectacular soundings there with great MLCAPE.

Agreed, figured I'd call attention to one minor negative aspect because otherwise they're very impressive soundings for this area. The limited back veer situation present actually improves on the NAM from 21-0z.

[snowlover2]

New Day 3

 

DAY 3 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   0231 AM CDT SAT MAY 18 2013
  
   VALID 201200Z - 211200Z
  
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE SRN
   PLAINS...CNTRL PLAINS...MID MS VALLEY...UPPER MS VALLEY AND GREAT
   LAKES REGION...
  
   ...REGIONAL SEVERE WEATHER EPISODE POSSIBLE ACROSS PARTS OF THE SRN
   AND CNTRL PLAINS INTO THE OZARKS MONDAY AFTERNOON AND EVENING...
  
   ...SRN AND CNTRL PLAINS/OZARK PLATEAU...
   AN UPPER-LEVEL LOW WILL REMAIN IN PLACE ACROSS THE NRN AND CNTRL
   PLAINS ON MONDAY WITH SOUTHWEST FLOW LOCATED FROM THE SRN PLAINS
   INTO THE MID MS VALLEY. AT THE SFC...A LOW IS FORECAST TO MOVE NEWD
   ACROSS THE SRN PLAINS WITH DEWPOINTS SOUTH AND EAST OF THE LOW IN
   THE MID TO UPPER 60S F. A CAPPING INVERSION IN PLACE FOR MUCH OF THE
   DAY...SHOULD WEAKEN BY LATE AFTERNOON ALLOWING FOR ROBUST CONVECTIVE
   INITIATION. MODEL FORECASTS DEVELOP SEVERAL CLUSTERS OF
   THUNDERSTORMS LATE MONDAY AFTERNOON FROM THE SFC LOW NEAR THE RED
   RIVER NEWD INTO CNTRL AND ERN OK. THE MODELS APPEAR TO ORGANIZE AN
   MCS ACROSS THE SRN PLAINS AND MOVE THIS CONVECTIVE SYSTEM NEWD INTO
   THE OZARKS DURING THE EVENING.
  
   FORECAST SOUNDINGS IN SRN OK AND NEAR THE RED RIVER IN NORTH TX AT
   00Z/TUE SHOW IMPRESSIVE THERMODYNAMIC AND SHEAR PROFILES WITH MLCAPE
   VALUES OF 2500 TO 3500 J/KG AND 0-6 KM SHEAR VALUES OF 45 TO 55 KT.
   THIS ENVIRONMENT SHOULD BE FAVORABLE FOR SUPERCELLS WITH LARGE HAIL.
   HAILSTONES OF GREATER THAN 2 INCHES IN DIAMETER WILL BE POSSIBLE
   WITH THE MORE DOMINANT SUPERCELLS. IN ADDITION...LOW-LEVEL
   HODOGRAPHS ALSO LOOK IMPRESSIVE WITH 0-3 KM STORM RELATIVE
   HELICITIES IN THE 400 TO 50O M2/S2 RANGE BY EARLY MONDAY EVENING.
   THIS SUGGESTS TORNADIC SUPERCELLS WILL BE POSSIBLE WITH A POTENTIAL
   FOR STRONG TORNADOES. IF MESOSCALE CONDITIONS COME TOGETHER AS THE
   MODELS SUGGEST...THEN A CLUSTER OF TORNADOES COULD OCCUR ACROSS
   PARTS OF THE SRN PLAINS LATE MONDAY AFTERNOON INTO THE EVENING. WIND
   DAMAGE WILL ALSO BE POSSIBLE WITH SUPERCELLS AND BOWING
   LINE-SEGMENTS. THE MAIN CONCERN ABOUT FORECASTING A SIGNIFICANT
   EVENT THIS FAR OUT...IS THAT MULTIPLE DAYS OF THUNDERSTORMS BETWEEN
   NOW AND MONDAY WILL LIKELY ALTER THE OUTCOME AND THAT THE SCENARIO
   WILL BE DIFFERENT THAN WHAT IS CURRENTLY PRESENTED BY THE MODELS.
  
   ...MID TO UPPER MS VALLEY/GREAT LAKES...
   AN UPPER-LEVEL LOW IS FORECAST TO REMAIN IN PLACE ACROSS THE NRN AND
   CNTRL PLAINS ON MONDAY AS A SHORTWAVE TROUGH ROTATES AROUND THE ERN
   SIDE OF THE UPPER-LEVEL LOW. THE SHORTWAVE TROUGH AND AN ASSOCIATED
   MID-LEVEL JET WILL HELP FOCUS CONVECTIVE DEVELOPMENT ACROSS THE MID
   TO UPPER MS VALLEY AND GREAT LAKES REGION MONDAY AFTERNOON. SFC
   DEWPOINTS ARE FORECAST TO BE IN THE LOWER TO MID 60S F ACROSS A
   BROAD CORRIDOR FROM THE MID MS VALLEY EXTENDING NEWD INTO THE LOWER
   OH VALLEY WHERE THE MODELS DEVELOP MODERATE INSTABILITY BY
   AFTERNOON. THIS COMBINED WITH MODERATE DEEP LAYER SHEAR
   PROFILES...ENHANCED BY THE MID-LEVEL JET...SHOULD SUPPORT SEVERE
   THUNDERSTORM DEVELOPMENT. THE SEVERE THREAT SHOULD DEVELOP ACROSS A
   BROAD AREA WHERE MESOSCALE FEATURES AND THE MAGNITUDE OF INSTABILITY
   WILL BECOME IMPORTANT FOR SEVERE THREAT COVERAGE.  WIND DAMAGE AND
   LARGE HAIL APPEAR TO BE THE GREATEST THREATS AT THIS TIME BUT MUCH
   UNCERTAINTY EXISTS CONCERNING HOW THE EVENT WILL PLAY OUT.

 

[RCNYILWX]

New Day 3

Beat me to it. I'd say this outlook was handled well, sig severe is possible even up here, but certainly more likely in the hatched 30% area, and as mentioned in the discussion, mesoscale details and lingering uncertainty need to be sorted out. Lots can change in 3 days. 

[IWXwx]

Beat me to it. I'd say this outlook was handled well, sig severe is possible even up here, but certainly more likely in the hatched 30% area, and as mentioned in the discussion, mesoscale details and lingering uncertainty need to be sorted out. Lots can change in 3 days. 

 

Very conditional this far north. But, hey, it's something to watch.

[Hoosier]

Agreed, figured I'd call attention to one minor negative aspect because otherwise they're very impressive soundings for this area. The limited back veer situation present actually improves on the NAM from 21-0z.

I've seen some differing points of view on the whole veer-back-veer thing...I know it can be detrimental if it occurs below 500 mb but is it less critical if it happens above 500 mb?

[Stebo]

I've seen some differing points of view on the whole veer-back-veer thing...I know it can be detrimental if it occurs below 500 mb but is it less critical if it happens above 500 mb?

This is usually what I go by unless the the change above 500mb is > 15 to 20 degrees in wind direction. Anything less than that I consider negligible.

[huronicane]

12z GFS today gives some profiles for N.IL look reminiscent of ones you'll typically see in the Plains for tornado days

 

12z NAM, on the other hand, look more like a damaging wind sounding.

[snowlover2]

New day 2 expands slight risk into most of western IL.

 

DAY 2 CONVECTIVE OUTLOOK 
   NWS STORM PREDICTION CENTER NORMAN OK
   1209 PM CDT SAT MAY 18 2013
  
   VALID 191200Z - 201200Z
  
   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PARTS OF KS/OK/WRN MO...
  
   ...THERE IS A SLGT RISK OF SVR TSTMS SURROUNDING THE MDT RISK FROM
   NCNTRL TX INTO SRN MN...
  
   ...REGIONAL SEVERE WEATHER OUTBREAK POSSIBLE ACROSS PARTS OF THE SRN
   PLAINS...CNTRL PLAINS AND LOWER MO VALLEY...
  
  
   ...SRN PLAINS TO LOWER MO VALLEY....
  
   LATEST MODEL GUIDANCE CONTINUES TO SUGGEST A SIGNIFICANT MID LEVEL
   SPEED MAX WILL EVOLVE WITHIN THE BASE OF THE WRN U.S. TROUGH OVER
   THE SRN ROCKIES LATE DAY1...THEN EJECT ACROSS THE SRN PLAINS TOWARD
   WRN MO BY 20/00Z.  THERE ARE MINOR DIFFERENCES AMONG THE 12Z NAM/GFS
   AND 00Z ECMWF...WITH THE NAM FAVORING A BIT MORE AGGRESSIVE SPEED
   MAX/HEIGHT FALLS ACROSS NERN OK INTO SWRN MO THAN THE OTHER
   GUIDANCE.  IT/S NOT ENTIRELY CLEAR IF THE MORE DISPLACED NAM SPEED
   MAX IS CORRECT...IF SO THEN SIGNIFICANT SEVERE TSTM ACTIVITY COULD
   SPREAD EAST OF DEPICTED MDT RISK.
  
   FOR NOW WILL OPT FOR SOMEWHAT SLOWER GFS SOLUTION AS IT HAS BEEN
   VERY CONSISTENT REGARDING THE FORECAST HEIGHT FIELD/WIND SPEEDS
   ACROSS THE SRN PLAINS INTO WRN MO.  GIVEN THIS SOLUTION...AT SUNRISE
   IT APPEARS SYNOPTIC FRONT WILL EXTEND FROM A SFC LOW OVER NCNTRL
   NEB...SWD ACROSS CNTRL KS INTO THE TX PANHANDLE.  A DRYLINE IS
   EXPECTED TO INTERSECT THE COLD FRONT OVER SWRN KS...EXTENDING SSWWD
   INTO NWRN TX.  EARLY MORNING CONVECTION WILL LIKELY BE CONFINED TO
   WARM ADVECTION ZONE ALONG THE NOSE OF THE LLJ ACROSS THE CNTRL
   PLAINS INTO THE MID MS VALLEY.  SOUTH OF THIS ACTIVITY STRONG WARM
   SECTOR BOUNDARY LAYER HEATING IS EXPECTED DURING THE
   DAY...ESPECIALLY SOUTH OF I-70 CORRIDOR ACROSS KS/OK/TX.
   COMBINATION OF STRONG HEATING AND STRENGTHENING WLY FLOW ALOFT WILL
   ALLOW DRYLINE TO MIX TO A POSITION FROM CNTRL KS...SSWWD ACROSS SWRN
   OK INTO NWRN TX BY 21Z.  IF HOWEVER THE NAM SOLUTION IS CORRECT THEN
   THE DRYLINE MAY MIX TO THE I-35 CORRIDOR BY LATE AFTERNOON.
  
   GIVEN THE EXPECTED INTENSE HEATING ALONG THE DRYLINE THERE IS AMPLE
   REASON TO BELIEVE DISCRETE SUPERCELL STRUCTURES WILL EVOLVE
   INITIALLY NORTH OF THE MID LEVEL JET CORE ACROSS KS...THEN SWD INTO
   OK.  THIS MAY OCCUR BY 21Z OVER KS AND BY 20/00Z ACROSS OK TO NEAR
   THE RED RIVER.  FORECAST SHEAR PROFILES STRONGLY FAVOR LONG-LIVED
   SUPERCELLS AND WHERE DEW POINTS HOLD IN THE UPPER 60S/LOWER
   70S...TORNADOES CAN BE EXPECTED.  GIVEN THE EXPECTED
   SHEAR/INSTABILITY THERE IS SUPPORT FOR STRONG TORNADOES.
   ADDITIONALLY...VERY LARGE HAIL SHOULD ACCOMPANY THIS ACTIVITY.
   MATURING COMPLEX OF STORMS SHOULD PROGRESS ACROSS KS/NERN OK INTO
   WRN MO WITH MORE SCATTERED ACTIVITY ACROSS CNTRL/SRN OK.
 

 

 

[OntarioChaser]

Some models are showing an interesting convective complex moving over L MI and S ON Monday evening through the night possibly riding the warm front.  What are your guys thoughts on this?

[Powerball]

Some models are showing an interesting convective complex moving over L MI and S ON Monday evening through the night possibly riding the warm front.  What are your guys thoughts on this?

 

I noticed that.

 

It appears the models try to develop an MCV and move it eastward.

 

The NAM in particular has a nice squall line blasting through here late in the afternoon.

[YHM Supercell]

I noticed that.

 

It appears the models try to develop an MCV and move it eastward.

 

The NAM in particular has a nice squall line blasting through here late in the afternoon.

Would be nice. NAM also has some good instability represented by MUCAPE around 1500-2500j/kg and pretty favourable vertical shear profiles for some damaging winds. Will have to keep an eye on this one.