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000
FXUS65 KRIW 120526 AAA
AFDRIW

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE RIVERTON WY
1126 PM MDT TUE JUN 11 2013

.SHORT TERM...TONIGHT AND WEDNESDAY
UPPER CIRCULATION IS WEAKENING BUT PASSING ACROSS OUR SERN ZONES
WITH A NWRN EXTENSION OF THE TROUGH AT BOTH THE SURFACE AND ALOFT.
STORMS FIRING ACROSS THE NW AND N WITH POTENTIAL FOR A FEW STRONG
TO SEVERE STORMS. ANY STORM COULD PRODUCE VERY STRONG AND ERRATIC
WIND GUSTS OVER 50 MPH. VERY DRY AIR ADVANCING FROM THE SW WITH
TEEN AND 20S DEW POINTS COVERING MUCH OF THE SWRN HALF. 50+ DEW
POINTS HOLDING IN THE FAR NCNTRL AND NERN ZONES BUT SOME OF THOSE
WILL ERODE. STORM POTENTIAL WILL CONTINUE HIGHEST IN NRN JOHNSON AND
ALONG THE MONTANA BORDER IN THE NRN BIG HORN BASIN. APPROACHING JET
STREAK ON WEDNESDAY WILL BRING THE THREAT OF SOME STRONG
THUNDERSTORMS ACROSS THE NW WHERE THE JET SUPPORT MAY COME INTO PLAY
ALONG WITH A LITTLE BETTER PW VALUES AND POTENTIALLY AGAIN IN THE
NRN BIG HORN BASIN AND JOHNSON COUNTY. THE SOUTH WILL CONTINUE DRY
..VERY WARM AND WINDY.

.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY

STUCK BETWEEN A DIRTY RIDGE AND LARGE TROUGH TO THE WEST. LOW
PRESSURE RIGHT OVER THE GUT OF CENTRAL WY...WITH EASTERLY TO
SOUTHEASTERLY SFC FLOW ACROSS PARTS OF NATRONA AND JOHNSON
COUNTIES...MAXIMIZING SHEAR IN THIS AREA BUT WITH MARGINAL MOISTURE
TO WORK WIT. STILL POTENTIAL FOR LOW END SEVERE IN THIS AREA EXISTS
WEDNESDAY NIGHT...ESPECIALLY FOR SEVERE WINDS. BETTER MOISTURE WILL
BE PRESENT OVER NWRN WY...BUT LESS SHEAR. OVERALL...POTENTIAL WILL
EXIST ACROSS THE NORTHERN TIER OF COUNTIES FROM WEST TO EAST.

THURSDAY... THE SFC LOW AND AND DRY SOUTHWEST FLOW INCHES NORTHWARD
AND WILL EFFECTIVE LIMIT CONVECTIVE ACTIVITY TO VERY HIGH BASED
STORMS ALONG SPEED CONVERGENCE AND ELEVATED TERRAIN REGIONS OF
SWEETWATER AND NATRONA COUNTIES...AND ADDITIONALLY ALONG/NEAR THE
WY/MT BORDER...ESPECIALLY IN AND NEAR YELLOWSTONE...THEN EASTWARD TO
THE BIG HORNS. NO SEVERE HOWEVER IS EXPECTED IN OUR CWA.

FRIDAY...BEST UPPER LEVEL SHORTWAVE TROUGH SWINGS THROUGH NW CORNER
OF CWA...BUT WILL HAVE VERY LITTLE TO WORK WITH...SO ONLY SMALL POPS
OVER EXTREME NW CWA AT THIS TIME. COLD FRONT ALSO FINALLY MOVES
THROUGH...BRINGING DOWN HIGH TEMPS SOME 10 TO 12 DEG. BIGGEST
CONCERN FOR THURSDAY AND FRIDAY WILL BE WARM DRY BREEZY TO WINDY
CONDITIONS ACROSS SWEETWATER AND PORTIONS OF NATRONA
COUNTIES...POSSIBLY RAISING SOME FIRE WX CONCERNS TO NEAR RED FLAG
CONDITIONS DEPENDING ON FUEL STATUS.

SATURDAY THROUGH TUESDAY...FLAT UPPER FLOW SAT REPLACE BY RIDGING
SUN AND MON DEMARKS THE TEMPERATURE TREND...WITH UPPER 80S TO AROUND
90 RETURNING ONCE AGAIN TO THE FORECAST SUNDAY AND MONDAY BEFORE
TEMPS BEHIND ANOTHER WEAK COLD FRONT. SLIGHT CHANCES FOR POPS WILL
EXIST SUN MON AND TUES AFTERNOONS OVER MAINLY THE THE
MOUNTAINS...BUT GENERALLY ROBUST UPPER LEVEL RIDGING WILL PREVAIL
OVER THIS PERIOD WITH LITTLE CHANCES FOR PRECIPITATION EXCEPT OVER
THE HIGH TERRAIN...UNTIL THE CLOSED TROUGH OVER THE PAC NW REGION
FEELS THE NEED MOVE THIS WAY. ATTM...MODELS ARE NOT SHOW IT LIFTING
OUT UNTIL MID TO END OF NEXT WEEK.

.AVIATION.../06Z ISSUANCE/

SOUTHWEST FLOW AT 15 TO 25KT ACROSS THE SOUTHERN WIND CORRIDOR
FROM KRKS TO KCPR BEGINS AGAIN TOWARD LATE MORNING AS MORE SHOWERS
AND THUNDERSTORMS MOVE INTO THE NORTH AND WEST...THERE WILL BE
MORE VCTS ACRS THE WEST TODAY THAN THERE WAS ON TUESDAY WITH A
BETTER CHANCE OF -GS AND STRONG WIND GUSTS VCNTY KCOD KWRL AND
KBYG...AS WELL AS MVFR CONDITIONS IN RA...WHILE HIGHER BASED
THUNDERSTORMS IN CENTRAL AREAS WILL PRODUCE VERY STRONG OUTFLOW
WINDS...IT WILL LIKELY BE TOO DRY FOR STORMS AGAIN VCNTY KRKS AND
KCPR. STORMS WILL EXIT THE AREA AFTER 06Z THU LEAVING BEHIND A FEW
HIGHER CLOUDS AND LIGHT WINDS.

.FIRE WEATHER...

A SERIES OF SYSTEMS WILL BRING SHOWERS AND THUNDERSTORMS ACROSS
NORTHERN AND WESTERN WYOMING OVER THE NEXT FEW DAYS. TUESDAY AND
WEDNESDAY MAY SEE SOME STRONGER STORM DEVELOPMENT ACROSS JOHNSON
COUNTY. THESE STRONGER WIND MAY HAVE SIGNIFICANT AND ERRATIC WIND
WITH INCREASED HAIL...IN ADDITION TO PERIODS OF HEAVY RAINFALL.
AREAS OF SOUTHERN WYOMING WILL AGAIN HAVE A WARM AND GENERALLY DRY
DAY...WITH HUMIDITY AGAIN DIPPING INTO THE SINGLE DIGITS THIS
AFTERNOON. HOWEVER...TEMPERATURES WILL COOL OVER THE NEXT COUPLE OF
DAYS UNDER THE INFLUENCE OF THESE SYSTEMS.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...SKRBAC
LONG TERM...BRAUN
AVIATION...ALLEN
FIRE WEATHER...SKRBAC