Bureau County Skywarn

STATUS FOR WATCH 0221 HAS NOT BEEN ISSUED YET

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 221
NWS STORM PREDICTION CENTER NORMAN OK
115 AM CDT SUN MAY 26 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
  NORTHERN AND CENTRAL SOUTH DAKOTA

* EFFECTIVE THIS SUNDAY MORNING FROM 115 AM UNTIL 900 AM CDT.

* PRIMARY THREATS INCLUDE...
  SEVERAL VERY LARGE HAIL EVENTS TO 2.5 INCHES IN DIAMETER
    POSSIBLE
  A FEW DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 75 MILES NORTHWEST
OF PHILIP SOUTH DAKOTA TO 55 MILES NORTH NORTHEAST OF CHAMBERLAIN
SOUTH DAKOTA.  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.

&&

DISCUSSION...SVR TSTMS CONTINUE TO FORM IN WAA ZONE ATOP
SHALLOW...SFC-BASED STABLE LAYER N OF WNW-ESE ORIENTED STNRY FRONT.
SUFFICIENT CLOUD-LAYER SHEAR APPEARS PRESENT FOR A FEW ELEVATED
SUSTAINED STORMS/SUPERCELLS WITH LARGE HAIL AND LOCALLY DMGG WIND.

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 500. MEAN STORM
MOTION VECTOR 30035.


...CORFIDI

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1233 AM CDT SUN MAY 26 2013

VALID 271200Z - 281200Z

...THERE IS A SLGT RISK OF SVR TSTMS FOR A LARGE PORTION OF THE
PLAINS AND MO RIVER VALLEY...

...SYNOPSIS...
A POWERFUL UPPER JET LOCATED OVER THE ERN PACIFIC WILL ACT TO
REINVIGORATE A LARGE-SCALE TROUGH OVER THE WRN STATES DURING THE
LATTER HALF OF THE DAY 2 PERIOD.  DOWNSTREAM OVER THE CNTRL
U.S...SEVERAL WEAK MID-LEVEL PERTURBATIONS WILL MOVE ACROSS THE
CNTRL-NRN PLAINS INTO THE MIDWEST WHILE THE PRIMARY SHORTWAVE TROUGH
MOVES FROM THE NRN ROCKIES INTO ERN MT BY THE EVENING. 
PLACEMENT/TIMING OF THESE SMALLER-SCALE FEATURES IS STILL
UNCERTAIN...BUT STRONG-SEVERE STORM ACTIVITY WILL PROBABLY ASSOCIATE
WITH AT LEAST ONE OF THESE IMPULSES MOVING ACROSS THE CNTRL PLAINS. 
AT THE SURFACE...A LOW/TRIPLE POINT OVER WRN KS AND AN ATTENDANT
TROUGH/DRYLINE WILL SERVE TO FOCUS THE PRIMARY SEVERE POTENTIAL
DURING THE AFTERNOON THROUGH THE EVENING HOURS.  

...CNTRL PLAINS...
WARM ADVECTION REGIME LIKELY ONGOING MONDAY MORNING OVER THE ERN
NEB/IA/NRN MO ON THE NOSE OF A LLJ WILL PROBABLY YIELD SCTD
SHOWERS/STORMS OVER THIS REGION INVOF OF A NW-SE ORIENTED FRONTAL
ZONE.  STORMS LOCATED ON THE SW FLANK OF THIS CLUSTER MAY POSE AN
ISOLD LARGE HAIL THREAT WHERE ACCESS TO GREATER H7-H5 LAPSE RATES
WOULD BE LOCATED ON THE ERN FRINGE OF THE EML.  

MOIST/STRONG SLY LOW LEVEL FLOW WILL ALLOW DEWPOINTS TO RISE INTO
THE MID 60S-70 DEG F E/SE OF THE SURFACE LOW FROM OK INTO KS/SRN NEB
BENEATH AN INITIAL STRONG CAP.  MODELS SHOW MID-LEVEL LAPSE RATES IN
EXCESS OF 8 DEG C/KM AND FORECAST SOUNDINGS SHOW MLCAPE RANGING FROM
2500-4000 J/KG OVER NEB/KS.  N/NE OF THE TRIPLE POINT...BACKED ELY
COMPONENT TO LOW LEVEL FLOW WOULD SUPPORT STRONG DEEP LAYER SHEAR
PROFILES /35-45 KT EFFECTIVE SHEAR/ WELL INTO THE SUPERCELL RANGE. 
STRONG HEATING DURING THE DAY WILL CONSIDERABLY WEAKEN THE CAP BY
AFTERNOON LEADING TO ISOLD-SCTD STORMS DEVELOPING.  LARGE TO VERY
LARGE HAIL AND DMGG WINDS ARE POSSIBLE WITH THE INITIAL
ACTIVITY...BUT AN INCREASING TORNADO THREAT MAY MATERIALIZE TOWARDS
THE EVENING AS LOW LEVEL SHEAR INCREASES IN RESPONSE TO AN
INTENSIFYING LLJ AND TEMP/DEWPOINT SPREADS LESSEN.  A POSSIBLE
UPSCALE TRANSITION MAY OCCUR DURING THE EVENING WITH A DMGG WIND
THREAT PERHAPS ENSUING AS STORMS MIGRATE EWD TOWARDS THE MO RIVER.

...NRN PLAINS...
A FRONTAL ZONE DRAPED OVER THE ERN DAKOTAS WILL ACT TO CONFINE THE
GREATER LOW LEVEL MOISTURE WWD OVER THE WRN DAKOTAS WITHIN SELY LOW
LEVEL FLOW AND ADJACENT NERN WY/ERN MT.  THE APPROACH OF THE
SHORTWAVE TROUGH OVER MT DURING PEAK HEATING WILL PROBABLY LEAD TO
ISOLD STORMS DEVELOPING...BOTH NEAR THE BLACK HILLS AND FARTHER NW
IN CLOSER PROXIMITY TO THE UPPER FORCING FOR ASCENT.  WIND PROFILES
WOULD SUPPORT STORM ORGANIZATION...WITH ISOLD LARGE HAIL AND DMGG
WINDS POSSIBLE.  

...SRN PLAINS...
THE DRYLINE WILL EXTEND SWD FROM THE TRIPLE POINT LOW THROUGH
PORTIONS OF WRN OK AND INTO W TX DURING THE AFTERNOON.  STRONG
HEATING INVOF OF THE DRYLINE WILL PROMOTE A DEEPLY MIXED BOUNDARY
LAYER FEATURING VERY STEEP SURFACE-H5 LAPSE RATES.  30-35 KT
EFFECTIVE SHEAR SUPPORTIVE OF ORGANIZED DISCRETE STORMS WOULD POSE
AN ATTENDANT LARGE HAIL/SEVERE WIND GUST THREAT WITH THIS ACTIVITY
BEFORE WANING DURING THE EVENING HOURS.

..SMITH.. 05/26/2013

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1247 AM CDT SUN MAY 26 2013

VALID 261200Z - 271200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS A LARGE PART OF THE
SRN...CNTRL AND NRN HIGH PLAINS...

...SYNOPSIS...

SYNOPTIC PATTERN WILL UNDERGO LITTLE CHANGE WITH A LOW AMPLITUDE
OMEGA BLOCKING REGIME FORECAST TO PERSIST THROUGH SUNDAY. SEVERAL
VORTICITY MAXIMA WILL MOVE THROUGH WRN U.S. UPPER LOW CIRCULATION
AND INTO THE CNTRL AND NRN HIGH PLAINS. AT THE SFC A LEE LOW WILL
PERSIST OVER ERN CO WITH A DRYLINE EXTENDING SWD THROUGH THE CNTRL
AND SRN HIGH PLAINS. QUASI-STATIONARY WNW-ESE ORIENTED FRONT SHOULD
EXTEND FROM THE MID MS VALLEY NWWD THROUGH NEB INTO WY. 

...NRN THROUGH CNTRL PLAINS...

PERSISTENT BROAD FETCH OF SLY-SSELY WINDS EAST OF LEE TROUGH WILL
CONTRIBUTE TO FURTHER MOISTENING OF THE BOUNDARY LAYER WITH MID TO
UPPER 60S DEWPOINTS LIKELY OVER PORTIONS OF THE CNTRL PLAINS AND
UPPER 50S TO NEAR 60 OVER THE NRN PLAINS. MEANWHILE...WSWLY FLOW
ALOFT WILL MAINTAIN FEED OF STEEP LAPSE RATE ABOVE THE MOIST AXIS.
THE ATMOSPHERE SHOULD BECOME MODERATELY UNSTABLE SUNDAY AFTERNOON
WITH AN AXIS OF 2000-3000 J/KG MLCAPE FROM ERN MT AND WRN SD SWD
INTO WRN/CNTRL NEB. STORMS SHOULD ONCE AGAIN DEVELOP OVER THE HIGHER
TERRAIN AND INTENSIFY AS THEY MOVE ENEWD INTO THE AXIS OF STRONGER
INSTABILITY. OTHER STORMS MAY INITIATE FARTHER SOUTH ALONG DRYLINE
ACROSS ERN CO/WRN KS. MUCH OF THIS REGION WILL EXIST ON SERN
PERIPHERY OF UPPER LOW CIRCULATION WITH 25-35 KT 500 MB FLOW ABOVE
SELY NEAR SFC WINDS SUPPORTING 30-40 KT EFFECTIVE SHEAR. SUPERCELL
MODES WILL BE LIKELY WITH INITIAL STORMS THAT DEVELOP WITH PRIMARY
THREAT BEING VERY LARGE HAIL. ISOLATED TORNADOES MAY ALSO BE
POSSIBLE. EVENTUALLY STORMS MAY EVOLVE INTO ONE OR MORE
CLUSTERS...AND ADDITIONAL STORMS MAY ALSO DEVELOP DURING THE EVENING
ACROSS NEB ON NOSE OF STRENGTHENING LLJ. 

...SRN HIGH PLAINS...

ISOLATED TO WIDELY SCATTERED STORMS MAY DEVELOP WITHIN ZONE OF
DEEPER MIXING ALONG DRYLINE ACROSS THE SRN HIGH PLAINS. STORMS WILL
INTENSIFY AS THEY MOVE INTO MOIST AXIS WITH 2000-3000 J/KG MLCAPE.
VERTICAL SHEAR WILL BE WEAKER THAN FARTHER NORTH...BUT 25-35 KT
EFFECTIVE SHEAR WILL SUPPORT MULTICELLS AND ALSO SOME SUPERCELL
STRUCTURES WITH LARGE HAIL AND DAMAGING WIND GUSTS THE MAIN THREATS
THROUGH MID EVENING.

..DIAL/DEAN.. 05/26/2013

STATUS REPORT ON WW 219

SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 WNW MRF
TO 10 SE INK TO 15 NW MAF TO 30 N BGS.

WW 219 WILL BE ALLOWED TO EXPIRE AT 260500Z.

..DEAN..05/26/13

ATTN...WFO...MAF...


STATUS REPORT FOR WS 219 

SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS 

NMC025-260500-

NM 
.    NEW MEXICO COUNTIES INCLUDED ARE

LEA                  


TXC003-109-165-301-389-475-495-260500-

TX 
.    TEXAS COUNTIES INCLUDED ARE

ANDREWS              CULBERSON           GAINES              
LOVING               REEVES              WARD                
WINKLER              


THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY.  PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.

STATUS REPORT ON WW 217

SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 W VTN TO
20 ESE PHP TO 40 NW PHP TO 55 SE 2WX TO 30 S 2WX TO 45 E 4BQ TO
10 E 4BQ TO 50 W 4BQ TO 55 NNW SHR.

FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0800

..DEAN..05/26/13

ATTN...WFO...BYZ...GGW...BIS...UNR...ABR...


STATUS REPORT FOR WT 217 

SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS 

MTC011-017-021-025-075-079-087-109-260340-

MT 
.    MONTANA COUNTIES INCLUDED ARE

CARTER               CUSTER              DAWSON              
FALLON               POWDER RIVER        PRAIRIE             
ROSEBUD              WIBAUX              


NDC001-007-011-015-029-033-037-041-059-085-087-089-260340-

ND 
.    NORTH DAKOTA COUNTIES INCLUDED ARE

ADAMS                BILLINGS            BOWMAN              
BURLEIGH             EMMONS              GOLDEN VALLEY       
GRANT                HETTINGER           MORTON              
SIOUX                SLOPE               STARK               


SDC031-041-055-063-075-105-117-137-260340-

STATUS REPORT ON WW 220

SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 NE MCK TO
35 SSW BBW TO 15 NE BBW TO 10 NNE BUB TO 20 SSW ONL.

FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0801

..DEAN..05/26/13

ATTN...WFO...GID...LBF...


STATUS REPORT FOR WS 220 

SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS 

NEC001-019-041-047-061-063-065-071-073-077-079-083-093-099-137-
163-175-183-260340-

NE 
.    NEBRASKA COUNTIES INCLUDED ARE

ADAMS                BUFFALO             CUSTER              
DAWSON               FRANKLIN            FRONTIER            
FURNAS               GARFIELD            GOSPER              
GREELEY              HALL                HARLAN              
HOWARD               KEARNEY             PHELPS              
SHERMAN              VALLEY              WHEELER             


THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY.  PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.

STATUS REPORT ON WW 218

SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 SSW HLC
TO 45 WSW HLC TO 50 E GLD TO 40 SSW MCK TO 10 SSE MCK TO 35 NE
MCK AND 50 S HLC TO 50 N GCK TO 45 SSE GLD TO 35 S ITR.

FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0801

..DEAN..05/26/13

ATTN...WFO...GLD...DDC...


STATUS REPORT FOR WS 218 

SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS 

KSC039-063-065-137-179-260340-

KS 
.    KANSAS COUNTIES INCLUDED ARE

DECATUR              GOVE                GRAHAM              
NORTON               SHERIDAN            


NEC145-260340-

NE 
.    NEBRASKA COUNTIES INCLUDED ARE

RED WILLOW           


THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY.  PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.