

908 

WWUS20 KWNS 272150

SEL1

SPC WW 272150

KSZ000-NEZ000-280500-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 231

NWS STORM PREDICTION CENTER NORMAN OK

450 PM CDT MON MAY 27 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  NORTHERN KANSAS

  SOUTHERN NEBRASKA



* EFFECTIVE THIS MONDAY AFTERNOON FROM 450 PM UNTIL MIDNIGHT CDT.



* PRIMARY THREATS INCLUDE...

  NUMEROUS TORNADOES LIKELY WITH SEVERAL INTENSE TORNADOES

    POSSIBLE

  NUMEROUS VERY LARGE HAIL EVENTS TO 4 INCHES IN DIAMETER LIKELY

  SEVERAL SIGNIFICANT DAMAGING WIND GUSTS TO 80 MPH POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 120 STATUTE

MILES EAST AND WEST OF A LINE FROM 20 MILES WEST NORTHWEST OF

HASTINGS NEBRASKA TO 55 MILES SOUTHWEST OF CONCORDIA KANSAS.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU1).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 227...WW 228...WW

229...WW 230...



DISCUSSION...RAPID SUPERCELL DEVELOPMENT IS UNDERWAY IN A ZONE OF

LOW-LEVEL WAA ACROSS S CENTRAL NEB...AND ADDITIONAL SUPERCELLS

SHOULD FORM JUST NE OF THE TRIPLE POINT IN N CENTRAL KS WHERE

LOW-LEVEL CONVERGENCE IS MAXIMIZED ALONG THE INSTABILITY AXIS...AS

CONVECTIVE INHIBITION WEAKENS.  THE COMBINATION OF MLCAPE OF

3500-4500 J/KG...EFFECTIVE BULK SHEAR OF 40-50 KT...EFFECTIVE SRH OF

250-400 M2/S2...AND BOUNDARY LAYER DEWPOINTS IN THE UPPER 60S WILL

SUPPORT THE RISK OF A FEW STRONG TORNADOES AND VERY LARGE HAIL.

LATER THIS EVENING INTO TONIGHT...THE STORMS WILL LIKELY CONGEAL

INTO AN MCS AND MOVE EWD/ESEWD ALONG THE RESIDUAL OUTFLOW/WARM FRONT

INTO NE KS/SE NEB.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

600. MEAN STORM MOTION VECTOR 27020.





...THOMPSON

