June 4-10, 2022 | Severe Storms (Quasi-zonal regime)

[ElectricStorm]

Looks like this morning MCS is stronger than expected here. Wonder if that will hurt our chances for a strong MCS tonight. Might not matter as much since it will be an overnight event though 

[snowlover2]

The 13z day 1 outlook says confidence is still too low for an upgrade to moderate but they also say a derecho is possible.

Quote

 Day 1 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0720 AM CDT Sun Jun 05 2022

   Valid 051300Z - 061200Z

   ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS WESTERN NE TO
   NORTHERN/CENTRAL OK...

   ...SUMMARY...
   Significant severe thunderstorms producing very large hail, intense
   damaging winds, and a few tornadoes are possible across parts of
   Oklahoma, Kansas, and Nebraska from late afternoon through tonight.

   ...OK/KS/NE...
   Although alluded to as a possibility in the 06Z outlook, confidence
   is too low to warrant an upgrade to a cat 4/MDT risk. Worst-case
   scenario could still support a derecho occurring this evening into
   the overnight somewhere in the region.

   A progressive MCS, which produced mainly strong wind gusts and a few
   measured severe early this morning, continues across far southeast
   KS and north-central to northeast OK. This MCS has not been terribly
   well-simulated by most CAM guidance, with the 00Z HRW-NSSL closest
   to reality. It's MCV will seemingly shift into the Ozark Plateau.
   Deep convection along its southwest flank may not entirely decay as
   low-level warm theta-e advection persists atop the convective
   outflow, a scenario supported by the HRW-NSSL. A farther south
   evolution of convective outflow would clearly suppress
   destabilization in eastern OK that is advertised by the bulk of
   guidance. Regardless of where convective outflow ultimately ends up,
   a very unstable air mass is expected to its west centered on western
   OK. Very steep mid-level lapse rates of 8.5-9 C/km will overspread
   upper 60s boundary-layer dew points to yield large buoyancy with
   MLCAPE in excess of 3000 J/kg. Modified air mass recovery is
   expected in the wake of the outflow across western parts of KS/NE.

   Guidance differs substantially with the degree of convective
   development near the outflow/dryline intersection centered around
   northwest OK. The HRW-NSSL, 00Z HRW-ARW, and 06Z NAM-NEST all
   suggest convection will develop around early evening near this
   intersection and along the cool side of the remnant outflow boundary
   into south-central KS as the low-level jet intensifies. This
   scenario would yield quick upscale growth and probable forward
   propagation south-southeast along the MLCAPE gradient. The 06Z HRRR
   and subsequent runs indicate no sustained deep convection occurring
   in the OK/KS border area during this time frame, despite having
   uncapped forecast soundings. The overall intensity and coverage of
   the severe threat with southern/eastern extent in OK will be
   modulated based on how far south/west this morning's MCS affects
   instability, and whether an MCS can develop during the evening
   versus overnight.

   A more probable convective signal exists along the lee
   trough/dryline across western NE to the KS/CO border. Robust
   boundary-layer heating to the west of the dryline will remove MLCIN
   for late afternoon scattered thunderstorm development. Several
   initial supercells in this regime will have the potential for
   significant severe hail given such steep mid-level lapse rates.
   Consolidating cold pools will likely yield upscale growth into a
   maturing MCS towards south-central NE and central KS during the
   evening. The overall intensity/coverage of the severe wind threat
   with this MCS will be modulated by whether a separate MCS will be
   simultaneously ongoing in far southern KS and OK. If the latter does
   not develop, a more favorable regime for significant severe wind
   gusts would be possible across central KS and then shifting into
   northern OK overnight.

   ...Interior Northwest...
   Within the left exit region of an intense upper jet centered on
   northern CA and southern OR, scattered thunderstorms are expected
   this afternoon from eastern OR across ID into a portion of western
   MT. Elongated, straight-line hodographs will encourage a few
   splitting supercells. However, buoyancy will likely remain weak with
   moderate mid-level lapse rates and below-normal surface
   temperatures. This suggests that isolated severe hail will be the
   primary hazard, with locally strong wind gusts a secondary threat.

   ..Grams/Broyles.. 06/05/2022

 

 

[snowlover2]

Keeping it enhanced at the 1630z update but also mention moderate could still be needed later.

Quote

DAY 1 CONVECTIVE OUTLOOK    
NWS STORM PREDICTION CENTER NORMAN OK  
1146 AM CDT SUN JUN 05 2022  
  
VALID 051630Z - 061200Z  
  
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS  
OF OKLAHOMA/KANSAS AND WESTERN NEBRASKA...  
   
..SUMMARY  
  
SIGNIFICANT SEVERE THUNDERSTORMS PRODUCING VERY LARGE HAIL, INTENSE  
DAMAGING WINDS, AND A FEW TORNADOES ARE POSSIBLE ACROSS PARTS OF  
OKLAHOMA, KANSAS, AND NEBRASKA FROM LATE AFTERNOON THROUGH TONIGHT.  
   
..KANSAS/NEBRASKA/OKLAHOMA  
  
A SEMI-ORGANIZED MCS CONTINUES SOUTHEASTWARD AT MIDDAY ACROSS  
EASTERN/SOUTHEAST OKLAHOMA. EPISODIC PULSE-TYPE SEVERE CORES MAY  
PERSIST ON ITS WESTERN FLANK FOR A TIME THIS AFTERNOON WHILE IT  
OTHERWISE SPREADS TOWARD THE OZARK PLATEAU AND ARKLATEX VICINITY.  
ISOLATED SEVERE HAIL ON ITS WESTERN FLANK IS THE MOST PROBABLE RISK,  
BUT SOME DIURNALLY RENEWED DAMAGING WIND POTENTIAL IS ALSO PLAUSIBLE  
DOWNSTREAM.  
  
TO THE WEST OF THIS MCS AND NEAR/WEST OF ITS RELATED OUTFLOW, A VERY  
UNSTABLE ENVIRONMENT WILL EVOLVE THIS AFTERNOON ACROSS THE HIGH  
PLAINS INCLUDING WESTERN NEBRASKA AND WESTERN/SOUTHERN KANSAS INTO  
OKLAHOMA. 12Z UPPER-AIR DATA FEATURED SEMI-COOL MID-LEVEL THERMAL  
PROFILES FOR EARLY JUNE AS NOTED FROM DODGE CITY/NORTH PLATTE  
OBSERVED SOUNDINGS WITH 500 MB TEMPERATURES AROUND -12C TO -13C,  
ALTHOUGH A NOTABLE CAPPING INVERSION WAS NOTED TO THE SOUTHWEST (12Z  
AMARILLO SOUNDING AROUND 14C AT 700 MB). RELATED HIGH PLAINS  
ELEVATED MIXED LAYER PLUME WILL PERSIST AND MODESTLY ADVECT/RECOVER  
EASTWARD TODAY ON THE WESTERN FRINGES OF THE LATE-NIGHT AND EARLY  
MORNING MCS NOW OVER EASTERN OKLAHOMA. THIS WILL BE ATOP MID/UPPER  
60S F SURFACE DEWPOINTS, WHICH WILL CONTRIBUTE TO AMPLE BUOYANCY  
WITH UPWARDS OF 3000+ J/KG MLCAPE IN THE AFOREMENTIONED CORRIDOR.  
  
STORMS ARE MOST LIKELY TO INITIALLY DEVELOP NEAR THE FRONT ACROSS  
NEBRASKA THIS AFTERNOON, WITH DEEP CONVECTIVE INITIATION IN/AROUND  
PEAK HEATING A BIT MORE UNCERTAIN (BUT STILL VERY PLAUSIBLE) ACROSS  
WESTERN/SOUTH-CENTRAL KANSAS AND NORTHWEST OKLAHOMA IN VICINITY OF  
THE OUTFLOW BOUNDARY AND LEE TROUGH/DRYLINE VICINITY. MULTIPLE  
SUB-REGIONAL CORRIDORS OF SEVERAL INTENSE SUPERCELLS CAN BE EXPECTED  
WITH INITIAL DEVELOPMENT. THIS INCLUDES POTENTIAL FOR VERY LARGE  
HAIL GIVEN THE LAPSE RATES/BUOYANCY RESERVOIR AND MODERATE  
DEEP-LAYER SHEAR, WHICH WILL BE ACCENTUATED BY RELATIVELY STRONG  
WEST/NORTHWESTERLY HIGH-LEVEL WINDS. A COUPLE OF TORNADOES ARE  
POSSIBLE AS WELL.  
  
CONSOLIDATING COLD POOLS WILL LIKELY YIELD UPSCALE GROWTH INTO A  
MATURING MCS TOWARDS SOUTH-CENTRAL NEBRASKA AND CENTRAL KANSAS  
DURING THE EVENING. THE OVERALL INTENSITY/COVERAGE OF THE SEVERE  
WIND THREAT WITH THIS MCS WILL BE MODULATED BY WHETHER A SEPARATE  
MCS WILL BE SIMULTANEOUSLY DEVELOPING/ONGOING IN FAR SOUTHERN KANSAS  
AND NORTHERN OKLAHOMA. ALTHOUGH THERE ARE TIMING/SPATIAL  
UNCERTAINTIES, AGGREGATE METEOROLOGICAL SCENARIO SUGGESTS A  
RELATIVELY HIGH NET POTENTIAL/PROBABILITY OF LARGE HAIL AND  
WIDESPREAD DAMAGING WINDS THIS EVENING INTO THE OVERNIGHT ACROSS  
PARTS OF SOUTHERN KANSAS AND OKLAHOMA.  
  
A MODERATE RISK UPGRADE COULD STILL BE WARRANTED LATER TODAY PENDING  
GREATER CONFIDENCE IN A CONFINED CORRIDOR OF INTENSE STORM  
DEVELOPMENT INCLUDING HIGHER-END WIND POTENTIAL THIS EVENING INTO  
THE OVERNIGHT. 

 

 

[snowlover2]

Marginal risk expanded into west OH and SEMI on updated day 2. They mention not enough confidence at this time to include greater probabilities. 2% tornado area added also which isn't too surprising.

Quote

DAY 2 CONVECTIVE OUTLOOK    
NWS STORM PREDICTION CENTER NORMAN OK  
1230 PM CDT SUN JUN 05 2022  
  
VALID 061200Z - 071200Z  
  
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE NORTHERN/CENTRAL PLAINS...  
   
..SUMMARY  
  
STRONG TO SEVERE THUNDERSTORMS APPEAR POSSIBLE MONDAY FROM PARTS OF  
THE NORTHERN/CENTRAL PLAINS TOWARD THE OZARKS, MID-SOUTH, AND  
MIDWEST. DAMAGING WIND GUSTS AND LARGE HAIL ARE THE MAIN HAZARDS  
EXPECTED WITH THIS ACTIVITY.  
   
..PORTIONS OF THE NORTHERN/CENTRAL PLAINS  
  
QUASI-ZONAL FLOW IS FORECAST TO PERSIST OVER MUCH OF THE ROCKIES AND  
HIGH PLAINS THROUGH THE PERIOD. STILL, INCREASING MID/UPPER-LEVEL  
WINDS ASSOCIATED WITH A JET WILL LIKELY OVERSPREAD PARTS OF THE  
NORTHERN/CENTRAL HIGH PLAINS BY MONDAY AFTERNOON. 40-50+ KT OF  
DEEP-LAYER SHEAR AND LONG/STRAIGHT HODOGRAPHS ALOFT WILL LIKELY  
FAVOR SUPERCELLS. LOW-LEVEL MOISTURE SHOULD REMAIN FAIRLY MODEST  
ACROSS THESE AREAS OWING TO PRIOR CONVECTION AND RELATED OUTFLOW  
BOUNDARIES SHUNTING RICH LOW-LEVEL MOISTURE MAINLY INTO THE SOUTHERN  
PLAINS. STILL, AT LEAST WEAK INSTABILITY IS FORECAST TO DEVELOP IN A  
NARROW CORRIDOR FROM PARTS OF NORTHERN WY INTO SD/NE/KS BY LATE  
MONDAY AFTERNOON AS DIURNAL HEATING OCCURS. MODESTLY STEEPENED  
MID-LEVEL LAPSE RATES SHOULD ALSO OVERSPREAD THIS REGION THROUGH THE  
DAY. 12 HREF MEMBERS ARE IN REMARKABLY GOOD AGREEMENT THAT MULTIPLE  
SUPERCELLS WITH ROBUST MID-LEVEL UH WILL DEVELOP AND SPREAD  
SOUTHEASTWARD THROUGH MONDAY EVENING/NIGHT WHILE POSING A THREAT FOR  
BOTH LARGE HAIL AND SEVERE WIND GUSTS. HAVE EXPANDED THE SLIGHT RISK  
FROM SOUTHEASTERN CO/WESTERN KS NORTHWARD TO ENCOMPASS PARTS OF THE  
NORTHERN/CENTRAL PLAINS TO ACCOUNT FOR THIS SUPERCELL POTENTIAL IN A  
FAIRLY NARROW CORRIDOR.  
  
FARTHER SOUTH ACROSS THE CENTRAL HIGH PLAINS OF EASTERN CO AND  
VICINITY, MODEST LOW-LEVEL UPSLOPE FLOW SHOULD EVENTUALLY ENCOURAGE  
ISOLATED TO SCATTERED CONVECTION TO DEVELOP AND SPREAD EASTWARD.  
THERE IS UNCERTAINTY REGARDING HOW MANY INTENSE THUNDERSTORMS WILL  
DEVELOP IN THIS AREA, BUT WEAK TO MODERATE INSTABILITY AND STRONG  
DEEP-LAYER SHEAR WILL CONDITIONALLY SUPPORT A THREAT FOR LARGE HAIL  
AND DAMAGING WINDS WITH ANY SUPERCELLS OR MULTICELLS THAT CAN  
DEVELOP. ONE OR MORE SMALL BOWING CLUSTERS MAY ULTIMATELY DEVELOP  
ACROSS KS MONDAY EVENING/NIGHT AND POSE A CONTINUED THREAT FOR  
SEVERE/DAMAGING WIND GUSTS.  
   
..OZARKS INTO THE MID-SOUTH AND MIDWEST  
  
THERE WILL LIKELY BE AN EXPANSIVE, REMNANT MCS ONGOING AT THE START  
OF THE PERIOD MONDAY MORNING ACROSS PARTS OF THE OZARKS. AS AN MCV  
AND ASSOCIATED MID-LEVEL SHORTWAVE TROUGH SPREAD EASTWARD ACROSS THE  
MID-SOUTH INTO THE MIDWEST THROUGH THE DAY, ADDITIONAL CONVECTIVE  
DEVELOPMENT MAY OCCUR. MID-LEVEL FLOW IS NOT FORECAST TO BE OVERLY  
STRONG, BUT 20-30 KT OF DEEP-LAYER SHEAR SHOULD BE SUFFICIENT FOR  
MODEST THUNDERSTORM ORGANIZATION. AS DIURNAL HEATING OCCURS AND  
INSTABILITY GRADUALLY INCREASES, MULTICELLS CAPABLE OF PRODUCING  
MAINLY STRONG TO DAMAGING WINDS ARE FORECAST TO SPREAD  
EAST-NORTHEASTWARD ACROSS THESE REGIONS THROUGH MONDAY EVENING  
BEFORE WEAKENING. HAVE EXPANDED THE MARGINAL RISK FOR WIND FROM  
PARTS OF THE SOUTHEAST TO THE MIDWEST TO ACCOUNT FOR PROBABLE AREAS  
OF MULTICELL DEVELOPMENT THROUGH THE LATE AFTERNOON. THERE WAS NOT  
ENOUGH CONFIDENCE IN A MORE FOCUSED CORRIDOR OF SEVERE POTENTIAL TO  
INCLUDE GREATER SEVERE WIND PROBABILITIES AT THIS TIME.  
  
..GLEASON.. 06/05/2022  

 

 

[StormfanaticInd]

Tomorrow will be heavily dependent on what happens to today's possible mcs/derecho 

[snowlover2]

18z HRRR for today.

[snowlover2]

ILN taking more notice about tomorrow in the new afternoon update.

Quote

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
The short term period turns a bit more active with the approach
of a well-defined/compact S/W by late afternoon into the
evening. This convectively-enhanced S/W, likely with a well-
defined MCV, will move into the western OH Vly by early
afternoon. A rather quick uptick in LL moisture/moisture
advection will coincide with some increased cloud cover locally
with the approach of this feature.

Until we get to the SHRA/TSRA, fcst soundings continue to show
decent mixing in the BL through at least 21z with steepening LL
lapse rates supporting breezy conditions. SSW winds around
10-15 MPH, and gusts to around 25 MPH, are expected during the
afternoon Monday. This will occur ahead of the shield of
SHRA/TSRA, which will be knocking on our western doorstep likely
by 21z or so.

Guidance has trended a bit more compact/robust with the
convectively-enhanced S/W that will approach the ILN FA during
the latter part of the daytime period. There may be one or more
MCV structures within the convective complex, which will
approach the ILN FA during a typically diurnally favorable time
period. While some solutions have trended a bit more aggressive
with the instby/destabilization, there is not yet a cohesive
signal on just how much SBCAPE will be able to develop with
rather poor midlevel lapse rates to contend with. That being
said, the midlevel flow is sufficient, with deep-layer/effective
shear on the order of 25+kts or so, to suggest some maintenance
of organization with the convection as it spills into the local
area late afternoon through the evening. The LL shear will
actually be a bit better than the deeper-layer shear, with some
hints of backing sfc winds and better directional shear in the
LL immediately ahead of the compact MCV/LL low structure. Any
convective structure that is able to orient itself more in a
N-S, or even NW-SE, direction is one that may pose an isolated
threat for strong, if not damaging, winds. There remains quite a
bit of uncertainty regarding how this is going to unfold given
the questions of deeper-layer destabilization owing to poor
midlevel lapse rates, but suffice to say that the forcing and
lift will become more than sufficient as we progress later into
the day/evening. This will all occur in an environment with
PWATs in excess of 1.5", suggesting, too, that efficient rain
rates can be expected with any/all activity with locally heavy
rain possible with activity that moves over the same areas in a
training fashion. Although most areas can expect to see one half
to three quarters of an inch of rain, some spots will likely
pick up in excess of 1 inch of rain through the nighttime
period.

The depiction of a compact S/W and attendant MCV structure into
the evening/overnight has certainly increased the degree to
which this evolution will be watched. With a more compact LL
pressure pattern, the associated wind fields may increase rather
substantially into the ILN FA late in the evening into the
overnight hours, with some solutions showing a 50-55+ kt H8 LLJ
developing into the local area past midnight. This is, of
course, dependent on the track and strength of the LL low
center. This increase in LL speed shear, even in an environment
lacking better sfc-based (or deep-layer) instby, will be
watched carefully as it may not take as strong of an
updraft/downdraft structure to translate stronger winds to the
surface. Will add mention of this low potential threat for
strong to isolated damaging winds and locally heavy rain to the
HWO, even with the aforementioned uncertainties, mainly for
locations near/W of I-75 corridor.

Widespread SHRA/TSRA will begin to taper off from W to E toward
daybreak, with the W-E oriented sfc front still trailing well
back to the W near/N of the I-70 corridor.

 

 

[snowlover2]

18z HRRR for Monday.

[snowlover2]

Supercell with 2" hail in N KS.

Quote

BULLETIN - EAS ACTIVATION REQUESTED
Severe Thunderstorm Warning
National Weather Service Hastings NE
243 PM CDT Sun Jun 5 2022

The National Weather Service in Hastings has issued a

* Severe Thunderstorm Warning for...
  Northern Rooks County in north central Kansas...
  Southwestern Smith County in north central Kansas...
  Northwestern Osborne County in north central Kansas...
  Southern Phillips County in north central Kansas...

* Until 330 PM CDT.

* At 242 PM CDT, severe thunderstorms were located along a line
  extending from near Phillipsburg to 8 miles southwest of Kirwin to
  near Webster State Park, moving east at 20 mph.

  HAZARD...Two inch hail and 60 mph wind gusts.

  SOURCE...Trained weather spotters.

  IMPACT...People and animals outdoors will be injured. Expect hail
           damage to roofs, siding, windows, and vehicles. Expect
           wind damage to roofs, siding, and trees.

* Severe thunderstorms will be near...
  Kirwin around 300 PM CDT.

Other locations in the path of these severe thunderstorms include
Alton, Stockton, Woodston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These are dangerous storms. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to shelter inside a strong building,  and stay away from
windows.

&&

LAT...LON 3975 9887 3952 9886 3926 9903 3937 9955
      3969 9950 3978 9939
TIME...MOT...LOC 1942Z 274DEG 18KT 3974 9924 3956 9921 3942 9939

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...OBSERVED
MAX HAIL SIZE...2.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

 

 

[snowlover2]

Staying with enhanced on the 20z update.

Quote

DAY 1 CONVECTIVE OUTLOOK    
NWS STORM PREDICTION CENTER NORMAN OK  
0300 PM CDT SUN JUN 05 2022  
  
VALID 052000Z - 061200Z  
  
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
OKLAHOMA/KANSAS AND WESTERN NEBRASKA...  
   
..SUMMARY  
  
SIGNIFICANT SEVERE THUNDERSTORMS PRODUCING VERY LARGE HAIL, INTENSE  
DAMAGING WINDS, AND A FEW TORNADOES REMAIN POSSIBLE ACROSS PARTS OF  
NEBRASKA, KANSAS, AND OKLAHOMA LATE THIS AFTERNOON THROUGH TONIGHT.  
   
..20Z UPDATE  
  
NO CHANGES HAVE BEEN MADE TO THE ENHANCED RISK EXTENDING FROM PARTS  
OF NE ACROSS KS AND INTO NORTHERN/CENTRAL OK. A ROBUST SUPERCELL  
PRODUCING LARGE HAIL HAS RECENTLY DEVELOPED OVER NORTH-CENTRAL KS ON  
THE EASTERN EXTENT OF PERSISTENT CLOUD COVER IN WESTERN KS. IT  
REMAINS SOMEWHAT UNCLEAR WHEN/WHERE ADDITIONAL INTENSE THUNDERSTORMS  
WILL DEVELOP ACROSS NORTHERN/CENTRAL KS THIS AFTERNOON AND EVENING.  
THERE WILL BE SOME POTENTIAL FOR CONVECTIVE INITIATION LATER THIS  
AFTERNOON INTO THE EARLY EVENING ALONG A DRYLINE/OUTFLOW BOUNDARY  
INTERSECTION IN THE SOUTHWESTERN KS TO NORTHWESTERN OK VICINITY.  
BUT, WARM MID-LEVEL TEMPERATURES ARE STILL CONTRIBUTING TO A  
SUBSTANTIAL CAP ACROSS THIS AREA BASED ON RECENT MESOANALYSIS  
ESTIMATES.  
  
ISOLATED TO SCATTERED THUNDERSTORMS APPEAR MORE PROBABLE TO DEVELOP  
ACROSS PARTS OF WESTERN INTO CENTRAL NE, NORTHWESTERN KS, AND FAR  
EASTERN CO ALONG A SURFACE TROUGH IN THE NEXT FEW HOURS AS MODEST  
UPSLOPE FLOW OCCURS AND A WEAK MID-LEVEL DISTURBANCE EJECTS OVER THE  
CENTRAL PLAINS. THIS MAY ALREADY BE OCCURRING ACROSS PARTS OF  
NORTHWESTERN NE. GIVEN THE PRESENCE OF STEEP MID-LEVEL LAPSE RATES  
AND ADEQUATE DEEP-LAYER SHEAR, VERY LARGE HAIL WILL BE A POSSIBILITY  
WITH ANY SUPERCELL THAT CAN BE SUSTAINED. OTHERWISE, A SOUTHERLY  
LOW-LEVEL JET THAT IS FORECAST TO STRENGTHEN THIS EVENING AND  
TONIGHT ACROSS THE SOUTHERN/CENTRAL PLAINS SHOULD AID IN UPSCALE  
GROWTH OF CONVECTION ACROSS PARTS OF CENTRAL/SOUTHERN KS AND PERHAPS  
NORTHERN OK. INTENSE, SEVERE WIND GUSTS WILL BE POSSIBLE IF THIS  
EVOLUTION INTO A BOWING MCS OCCURS. BUT, THERE IS STILL SUBSTANTIAL  
UNCERTAINTY REGARDING THE MOST FAVORED CORRIDOR FOR THIS POTENTIALLY  
SIGNIFICANT MCS.  
  
SOME EXPANSION TO THE MARGINAL RISK HAS BEEN MADE ACROSS PARTS OF  
CENTRAL/EASTERN OR INTO EASTERN WA BASED ON RECENT OBSERVATIONAL AND  
RADAR TRENDS. ISOLATED HAIL AND LOCALLY DAMAGING WINDS REMAIN  
POSSIBLE WITH ANY OF THE STRONGER CORES THAT CAN DEVELOP ACROSS THE  
INTERIOR PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES. SEE MESOSCALE  
DISCUSSION 1038 FOR MORE DETAILS ON THE SHORT-TERM SEVERE THREAT  
ACROSS THIS REGION.  
  
..GLEASON.. 06/05/2022

 

 

[snowlover2]

Quote

Mesoscale Discussion 1039
   NWS Storm Prediction Center Norman OK
   0312 PM CDT Sun Jun 05 2022

   Areas affected...parts of northern and central Kansas

   Concerning...Severe potential...Watch possible 

   Valid 052012Z - 052215Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Convection developing over portions of north-central
   Kansas seems likely to increase in coverage over the next couple of
   hours, turning southeastward with time.  WW may be required.

   DISCUSSION...Latest radar loop shows a small cluster of strong
   updrafts over the Phillips/Rooks County KS vicinity, northeast of
   the more cloudy/capped airmass that lingers across southwestern KS
   at this time.  This convection is occurring within the gradient on
   the eastern fringe of the axis of greatest mixed-layer CAPE over
   western Kansas, but still within a thermodynamic environment
   sufficient to support severe potential -- mainly in the form of
   large hail.

   Various CAM runs differ with respect to convective evolution with
   time, and given effects of the prior/overnight MCS, uncertainty
   persists in the short term.  Still, it appears likely that this
   cluster will gradually increase in coverage, and shift southeastward
   with time, on the northeastern fringe of the more capped
   environment.  Given the amply veering/increasing flow field with
   height supporting potential for severe weather, watch issuance is
   being considered for portions of the central Kansas vicinity.

   ..Goss/Guyer.. 06/05/2022

 

 

[snowlover2]

Quote

   Mesoscale Discussion 1040
   NWS Storm Prediction Center Norman OK
   0316 PM CDT Sun Jun 05 2022

   Areas affected...Western Nebraska into Eastern Colorado and
   northwest Kansas

   Concerning...Severe potential...Watch possible 

   Valid 052016Z - 052215Z

   Probability of Watch Issuance...60 percent

   SUMMARY...The probability of damaging winds and large hail is
   increasing as thunderstorms develop from northwest Nebraska into
   eastern Colorado and northwest Kansas. Trends will continue to be
   monitored, and a watch is possible.

   DISCUSSION...Thunderstorms initiating in the vicinity of a surface
   low along the western NE/SD border have shown periodic
   intensification over the past hour with a general increase in storm
   coverage. To the south, initial attempts at initiation are noted
   along a diffuse surface trough along the CO/NE border and into
   east-central CO. Additional attempts at initiation are possible as a
   mid-level wave (noted in afternoon water-vapor imagery) moves across
   the region. Although most of this activity is developing within a
   more deeply-mixed air mass, MLCAPE values in the 500-1000 J/kg
   range, coupled with 30-40 knot zonal effective bulk shear vectors,
   will support maturing convection through the late afternoon. As
   storms meander east during the late afternoon/early evening they
   will move into an axis of better boundary-layer moisture/higher
   instability that will augment the potential for intense convection.
   Initially discrete supercells will pose a threat for large (to
   perhaps very large) hail as this intensification occurs. Steep
   low-level lapse rates (between 8-9 C/km) will allow for strong
   outflows that may lead to eventual clustering and upscale growth.
   Some guidance hints that this clustering could become more organized
   into a forward propagating MCS late tonight as the nocturnal
   low-level jet increases, but confidence in this scenario is low
   given notable spread in hi-res solutions. Regardless, a watch may be
   needed to address the potential for robust discrete convection.

   ..Moore/Guyer.. 06/05/2022

 

 

[snowlover2]

Quote

URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 310
   NWS Storm Prediction Center Norman OK
   350 PM CDT Sun Jun 5 2022

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Eastern Colorado
     Western and North-Central Kansas
     Southwest Nebraska

   * Effective this Sunday afternoon and evening from 350 PM until
     1000 PM CDT.

   * Primary threats include...
     Scattered large hail likely with isolated very large hail events
       to 2.5 inches in diameter possible
     Scattered damaging wind gusts to 70 mph likely
     A tornado or two possible

   SUMMARY...Multiple corridors of severe storm development including a
   few supercells will continue to occur, initially along/north of
   Interstate 70 vicinity from eastern Colorado into
   northwest/north-central Kansas. Large hail and damaging winds are
   possible with the storms. Multiple storm clusters may ultimately
   emerge by evening with an increased damaging wind potential.

   The severe thunderstorm watch area is approximately along and 65
   statute miles north and south of a line from 45 miles east northeast
   of Russell KS to 50 miles west southwest of Burlington CO. For a
   complete depiction of the watch see the associated watch outline
   update (WOUS64 KWNS WOU0).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   2.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 550. Mean storm motion vector
   31020.

   ...Guyer

 

 

[snowlover2]

Quote

 URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 311
   NWS Storm Prediction Center Norman OK
   405 PM CDT Sun Jun 5 2022

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Western and South-Central Nebraska

   * Effective this Sunday afternoon and evening from 405 PM until
     1000 PM CDT.

   * Primary threats include...
     Scattered large hail and isolated very large hail events to 2
       inches in diameter likely
     Scattered damaging wind gusts to 70 mph possible
     A tornado or two possible

   SUMMARY...Multiple corridors of increasing severe thunderstorm
   development are expected through early evening, initially across
   west-central/southwest Nebraska. Storms will likely reach
   south-central Nebraska this evening.

   The severe thunderstorm watch area is approximately along and 80
   statute miles east and west of a line from 25 miles west of
   Ainsworth NE to 55 miles west southwest of Kearney NE. For a
   complete depiction of the watch see the associated watch outline
   update (WOUS64 KWNS WOU1).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 310...

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 550. Mean storm motion vector
   31025.

   ...Guyer

 

 

[ClicheVortex2014]

Gonna be crazy tonight. Also excited about MCV storms tomorrow

[ClicheVortex2014]

Won't be surprised at all if there's at least one strong tornado (whether it's officially rated or not). From what I've seen, S KS/N OK is pretty much only missing low-level speed shear. But something could come along and negate that. We've also seen monster tornadoes happen with pretty weak low-level winds. Some of these soundings I'm seeing is a bit too weak, but wouldn't take much to make it borderline.

[ClicheVortex2014]

Possible tornado in E CO

[snowlover2]

2 minutes ago, ClicheVortex2014 said:

Possible tornado in E CO

And 3" hail.

Quote

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Pueblo CO
442 PM MDT Sun Jun 5 2022

The National Weather Service in Pueblo has issued a

* Tornado Warning for...
  Northwestern Prowers County in southeastern Colorado...
  South central Kiowa County in southeastern Colorado...

* Until 515 PM MDT.

* At 441 PM MDT, a severe thunderstorm capable of producing a tornado
  was located 7 miles east of Queens Reservoir, or 16 miles north of
  Lamar, moving south at 25 mph.

  HAZARD...Tornado and hail up to three inches in diameter.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without
           shelter. Mobile homes will be damaged or destroyed.
           Damage to roofs, windows, and vehicles will occur.  Tree
           damage is likely.

* This tornadic thunderstorm will remain over mainly rural areas of
  northwestern Prowers and south central Kiowa Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3834 10256 3833 10249 3811 10242 3814 10263
TIME...MOT...LOC 2241Z 011DEG 21KT 3830 10252

TORNADO...RADAR INDICATED
MAX HAIL SIZE...3.00 IN

 

 

[btbucks]

At least it's raining where they really need it.

[ClicheVortex2014]

Using clouds to see directional shear: 101

(See Kansas)

Edited June 5, 2022 by ClicheVortex2014

[ClicheVortex2014]

Something interesting to watch... got a couple dry slots within the warm sector. If it sticks around, those areas would have an enhanced damaging wind threat/lower tornado threat. These slots are the result of intense convective overturning from the morning/early afternoon MCS. 

So the area to watch is really the outflow boundary left from the MCS. Enhanced moisture and temp gradient.

It's certainly possible S KS/N OK recovers in the coming hours due to prolonged moisture advection from Arkansas, and the nocturnal LLJ will also help.

Edited June 5, 2022 by ClicheVortex2014

[snowlover2]

Quote

 Mesoscale Discussion 1043
   NWS Storm Prediction Center Norman OK
   0709 PM CDT Sun Jun 05 2022

   Areas affected...central Nebraska into western Kansas and vicinity

   Concerning...Severe Thunderstorm Watch 310...311...

   Valid 060009Z - 060215Z

   The severe weather threat for Severe Thunderstorm Watch 310, 311
   continues.

   SUMMARY...A threat of damaging winds and hail continues across the
   region, and may increase over the next few hours across western
   Kansas.

   DISCUSSION...Numerous storms across the region have produced several
   outflow boundaries which may act to temporarily stabilize the air
   mass. However, pockets of strong instability and an increasing
   southerly low-level jet tonight should allow for air mass recovery.

   One prominent outflow is surging westward across north-central KS
   and south-central NE, and towering CU have increased along this
   boundary as it moves into the instability axis into western KS.

   Meanwhile, storms are increasing in coverage from central NE into
   far northwest KS along a cold front, with multiple large hail cores
   noted. With time, it is believed that outflow will link and cause
   storms to grow into an MCS, with south/southeastward motion favored
   down the instability axis. Pockets of stable outflow may
   complicate/interrupt a potential MCS, but the overall scenario has
   potential and will be monitored through tonight.

   ..Jewell.. 06/06/2022

 

 

[ClicheVortex2014]

Not sure I've seen a 60% chance for a watch in an enhanced risk. Might not be an enhanced risk with the incoming update.

 Mesoscale Discussion 1044
   NWS Storm Prediction Center Norman OK
   0732 PM CDT Sun Jun 05 2022

   Areas affected...Parts of southwest/south-central KS and northern OK

   Concerning...Severe potential...Watch possible 

   Valid 060032Z - 060300Z

   Probability of Watch Issuance...60 percent

   SUMMARY...The area is being monitored for an increasing severe risk
   into this evening. A watch could eventually be needed for parts of
   the area.

   DISCUSSION...Latest visible satellite loops show recovering
   sheltered boundary layer air and backed surface winds over parts of
   southwest/south-central KS into northern OK ahead of a weak surface
   low and dryline evident over the TX/OK Panhandles. While this air
   remains slightly capped amid generally weak large-scale ascent per
   the DDC 00z sounding and visible satellite imagery, a few deepening
   cumulus towers are becoming evident along the eastern and southern
   edge of anvil debris overspreading the area from eastern CO. As lift
   along the nose of a strengthening low-level jet advances northward
   this evening in conjunction with a passing shortwave trough,
   eventual convective initiation will be possible where surface
   convergence is being maximized ahead of the surface low, though
   large uncertainty remains. 

   If isolated convection can initiate along this corridor prior to
   substantial nocturnal boundary-layer cooling, increasingly large,
   clockwise-turning low-level hodographs (200-400+ m2/s2 effective
   SRH) amid strong instability would support a discrete supercell or
   two along the KS/OK border capable of all hazards prior to upscale
   growth with southward extent. Timing and location of convective
   initiation and subsequent evolution is still unclear, though current
   thinking is that a watch could eventually be needed for parts of the
   area this evening.

 

[ClicheVortex2014]

3 minutes ago, ClicheVortex2014 said:

Not sure I've seen a 60% chance for a watch in an enhanced risk. Might not be an enhanced risk with the incoming update.

 Mesoscale Discussion 1044
   NWS Storm Prediction Center Norman OK
   0732 PM CDT Sun Jun 05 2022

   Areas affected...Parts of southwest/south-central KS and northern OK

   Concerning...Severe potential...Watch possible 

   Valid 060032Z - 060300Z

   Probability of Watch Issuance...60 percent

   SUMMARY...The area is being monitored for an increasing severe risk
   into this evening. A watch could eventually be needed for parts of
   the area.

   DISCUSSION...Latest visible satellite loops show recovering
   sheltered boundary layer air and backed surface winds over parts of
   southwest/south-central KS into northern OK ahead of a weak surface
   low and dryline evident over the TX/OK Panhandles. While this air
   remains slightly capped amid generally weak large-scale ascent per
   the DDC 00z sounding and visible satellite imagery, a few deepening
   cumulus towers are becoming evident along the eastern and southern
   edge of anvil debris overspreading the area from eastern CO. As lift
   along the nose of a strengthening low-level jet advances northward
   this evening in conjunction with a passing shortwave trough,
   eventual convective initiation will be possible where surface
   convergence is being maximized ahead of the surface low, though
   large uncertainty remains. 

   If isolated convection can initiate along this corridor prior to
   substantial nocturnal boundary-layer cooling, increasingly large,
   clockwise-turning low-level hodographs (200-400+ m2/s2 effective
   SRH) amid strong instability would support a discrete supercell or
   two along the KS/OK border capable of all hazards prior to upscale
   growth with southward extent. Timing and location of convective
   initiation and subsequent evolution is still unclear, though current
   thinking is that a watch could eventually be needed for parts of the
   area this evening.

 

I think I might be dumb. I didn't read all of the discussion before posting. Sounds like this isn't for the main part of the event for the area. It's for the chance for a discrete supercell as HRRR has been hinting. 60% chance if more about IF storms develop, rather than the usual scenario where they're not sure if the storms that develop will be strong enough to warrant a watch.

Edited June 6, 2022 by ClicheVortex2014

[ClicheVortex2014]

0z soundings

OUN: Impressive EML, impressive low-level shear, but serious low-level instability issues. Very strong directional shear, seasonably strong deep-layer shear.

 

DDC... weak low-level instability, impressive EML, weak low-level speed shear, strong deep-layer shear, very strong directional shear. Gonna be good for hail and wind unless low-level speed shear can strengthen.

Edited June 6, 2022 by ClicheVortex2014