893  
WWUS20 KWNS 122057  
SEL9  
SPC WW 122057  
COZ000-KSZ000-NEZ000-SDZ000-130500-  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
SEVERE THUNDERSTORM WATCH NUMBER 449  
NWS STORM PREDICTION CENTER NORMAN OK  
300 PM MDT SAT AUG 12 2017  
 
THE NWS STORM PREDICTION CENTER HAS ISSUED A  
 
* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF  
EASTERN COLORADO  
NORTHWEST KANSAS  
WESTERN NEBRASKA  
SOUTHERN SOUTH DAKOTA  
 
* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 300 PM UNTIL  
1100 PM MDT.  
 
* PRIMARY THREATS INCLUDE...  
SCATTERED LARGE HAIL LIKELY WITH ISOLATED VERY LARGE HAIL EVENTS  
TO 3 INCHES IN DIAMETER POSSIBLE  
ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE  
A TORNADO OR TWO POSSIBLE  
 
SUMMARY...MULTIPLE CORRIDORS OF SEVERE THUNDERSTORMS ARE EXPECTED TO  
CONTINUE TO INCREASE ACROSS THE REGION THROUGH THE REMAINDER OF THE  
AFTERNOON INTO EVENING. THE ENVIRONMENT WILL SUPPORT SUPERCELLS  
CAPABLE OF LARGE HAIL. CLUSTERS OF SOUTHEASTWARD-MOVING STORMS WILL  
ALSO EVOLVE WITH DAMAGING WINDS AND ADDITIONAL CONCERN.  
 
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 90  
STATUTE MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH OF  
VALENTINE NE TO 25 MILES WEST SOUTHWEST OF BURLINGTON CO. FOR A  
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE  
UPDATE (WOUS64 KWNS WOU9).  
 
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 447...WW 448...  
 
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO  
3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A  
FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR  
31025.  
 
...GUYER  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SPC Page Main Text Page