

826 

WWUS20 KWNS 250108

SEL9

SPC WW 250108

MTZ000-250800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 359

NWS STORM PREDICTION CENTER NORMAN OK

700 PM MDT MON JUN 24 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHERN AND EASTERN MONTANA



* EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 700 PM

  UNTIL 200 AM MDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL VERY LARGE HAIL EVENTS TO 2.5 INCHES IN DIAMETER

    POSSIBLE

  A FEW SIGNIFICANT DAMAGING WIND GUSTS TO 75 MPH POSSIBLE

  A FEW TORNADOES POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 60 MILES SOUTHWEST

OF HAVRE MONTANA TO 10 MILES NORTHEAST OF SIDNEY MONTANA.  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 356...WW 357...WW 358...



DISCUSSION...TSTMS EXPECTED TO INCREASE IN COVERAGE AND POSSIBLY

STRENGTH THROUGH LATE TNGT IN ZONE OF LOW-LVL WAA/MOISTURE INFLOW

ALONG AND N OF WEAK WNW-ESE STNRY FRONT. DEVELOPMENT AFTER SUNSET

WILL BE ENCOURAGED BY APPROACH OF UPSTREAM UPR-LVL DISTURBANCE AND

BY LOW-LVL-ASCENT ALONG NE-MOVING OUTFLOW BOUNDARIES FROM STORMS NOW

IN CNTRL/SRN MT. MOISTENING/BACKED LOW-LVL WINDS N OF FRONT COULD

YIELD A FAVORABLE ENVIRONMENT FOR TORNADOES WERE UPDRAFTS TO REMAIN

STRONG/DISCRETE. PART OF THIS WW MIGHT REQUIRE UPGRADE TO TORNADO

LATER THIS EVE IF SUCH EVOLUTION DOES OCCUR.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 65

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM

MOTION VECTOR 23025.





...CORFIDI

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