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000
FXUS65 KRIW 092120
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
320 PM MDT SUN MAR 9 2014

.SHORT TERM...TONIGHT THROUGH MONDAY

ISSUED WINTER WEATHER ADVISORY FOR THE WESTERN MOUNTAINS TONIGHT
THROUGH TUESDAY FOR HEAVY WET SNOW.  WILL EXTEND THE AREAL FLOOD
ADVISORIES ACROSS THE WEST AND NORTH THROUGH 4 PM MONDAY.  THE
WESTERN VALLEYS WILL SEE RAINFALL TONIGHT AND MONDAY...MIXED WITH
SNOW AT TIMES WHICH SHOULD MELT RATHER QUICKLY. RAINFALL OF .25 TO
.50 OF AN INCH CAN BE EXPECTED IN THE STAR VALLEY AND JACKSON
HOLE. LOCAL AMOUNTS MAY REACH .75 OF AN INCH. THIS IS EXPECTED TO
CAUSE AN INCREASE IN LOCAL SNOW MELT FLOODING WITH MELTING BELOW
7800 FEET.  HIGH WIND THREAT CONTINUES IN PARK COUNTY THROUGH
9 PM MDT THIS EVENING. TEMPERATURES WILL COOL IN THE WEST AND
REMAIN ON THE MILD SIDE EAST OF THE CONTINENTAL DIVIDE ON MONDAY.

.LONG TERM...MONDAY NIGHT THROUGH SUNDAY

SNOWFALL WILL CONTINUE IN THE WEST WITH A RAIN SNOW MIX IN THE
VALLEYS. THE RAIN AND SNOW WILL SPREAD ACROSS THE NORTH MONDAY
EVENING AND SPREAD SOUTH THROUGH THE NIGHT BECOMING ALL SNOW
ENDING UP ALONG THE CONTINENTAL DIVIDE. SNOWFALL WILL BE HEAVIEST
IN THE MOUNTAINS AND THEN SHIFT TO THE UPSLOPE FAVORED AREAS
OF EAST AND NORTH FACING SLOPES. SNOWFALL WILL CONTINUE TUESDAY
TAPERING OFF IN THE FAR WEST AND NORTH THROUGH THE AFTERNOON.
THE SNOW MAY MIX WITH RAIN AT TIMES WITH TEMPERATURES COOLING
SIGNIFICANTLY MONDAY NIGHT THROUGH TUESDAY NIGHT. SNOWFALL SHOULD COME
TO AN END WITH PARTIAL CLEARING TUESDAY NIGHT WITH AREAS OF FOG
DEVELOPING IN THE VALLEYS.

NO CHANGES THROUGH THE EXTENDED PERIOD. HIGH PRESSURE WILL WILL
REMAIN IN CONTROL THROUGH FRIDAY AFTERNOON...WITH MOSTLY CLEAR
SKIES. AFTERNOON TEMPERATURES IN THE 40S AND 50S WILL RETURN
THURSDAY AND FRIDAY. THESE WILL AID IN QUICKLY MELTING THE FRESH
SNOW FROM THE MON/TUE STORM...AS WELL AS THE DEEP SNOW COVER ACROSS
WESTERN PORTIONS...AND THAWING THE GROUND. FLOODING CONCERNS WILL
RETURN WITH THIS PATTERN DUE TO THESE CONDITIONS.

A QUICK HITTING DISTURBANCE WILL MOVE THROUGH EARLY SATURDAY
MORNING...AND BE OUT OF THE AREA BY SUNDAY MORNING. AREAS OF SNOW
WILL BE POSSIBLE BEFORE SUNRISE SATURDAY...CHANGING OVER TO RAIN IN
THE LOWER ELEVATIONS DURING THE DAY. DUE TO THE RELATIVE SPEED OF
THIS SYSTEM...NOT EXPECTING ANY MAJOR ISSUES. HOWEVER...WITH THE
ALREADY SATURATED GROUND...IT WILL NOT HELP. CLEARING AND DRY
CONDITIONS WILL RETURN FOR SUNDAY. HIGH CLOUDS MAY ALSO RETURN
ACROSS THE AREA BY SUNDAY...WHICH COULD SLOW DOWN THE SNOW
MELT.

&&

.AVIATION.../00Z ISSUANCE/

EAST OF THE DIVIDE...KCOD/KCPR/KLND/KRIW/KWRL ROUTES

VFR CONDITIONS WILL OCCUR THROUGH 18Z MONDAY.  OVER THE MOUNTAINS
ALONG AND NEAR THE CONTINENTAL DIVIDE ABOVE 8500 FEET MVFR TO IFR
CEILINGS AND VISIBILITIES REDUCED IN SNOW WILL INCREASE BECOMING
WIDESPREAD BY 09Z MONDAY. GUSTY WIND CONDITIONS AROUND THE KCOD
AND KCPR TERMINAL SITE THROUGH MOST OF THE PERIOD. STRONG MID
LEVEL WIND SPEEDS WILL OCCUR WHICH WILL CAUSE SOME WIND SHEAR AT
TIMES OVER THE NEAR THE MOUNTAINS. LOW LEVEL WIND SHEAR IS LIKELY
AT KLND AND KCOD. MVFR CONDITIONS WITH LOW CEILINGS AND RAIN/SNOW
SHOWERS WILL MOVE INTO FAR NORTH AREAS AFTER 22Z.

WEST OF THE DIVIDE...KBPI/KJAC/KPNA/KRKS ROUTES

OVER THE MOUNTAINS ABOVE 8500 FEET MVFR TO IFR CEILINGS AND
VISIBILITIES REDUCED IN SNOW WILL INCREASE BECOMING WIDESPREAD BY
03Z MONDAY. THE MVFR TO IFR CONDITIONS WILL SPREAD DOWN INTO THE
WESTERN VALLEYS IMPACTING KJAC AND KAFO BECOMING PREVALENT BY
06Z...SPREADING EAST TO KBPI...KPNA AND KEMM, STRONG SURFACE AND
LOW LEVEL WINDS WILL OCCUR OVER THE SOUTHWEST AND OVER THE
MOUNTAINS ABOVE 9000 FEET.

&&

.FIRE WEATHER...

INVERSIONS AND POOR SMOKE DISPERSAL ARE EXPECTED TONIGHT
THE BASINS AND VALLEYS. STRONG WEST SOUTHWEST WINDS WILL BLOW
FROM SOUTH PASS TO CASPER AS WELL AS ALONG THE CODY FOOTHILLS AND
EAST SLOPE OF THE CONTINENTAL DIVIDE.  AREAS OF LIGHT SNOW WILL
DEVELOP IN WESTERN WYOMING WITH THE SNOWFALL BECOMING STEADIER
AND HEAVIER TONIGHT AND INTO MONDAY ALONG WITH A MIX OF RAIN AND
SNOW OR ALL RAIN AT TIMES IN THE WESTERN VALLEYS. ALL SNOW WILL
CONTINUE MONDAY NIGHT AND SPREAD TO AREAS EAST OF THE DIVIDE
MONDAY NIGHT AND TUESDAY. SIGNIFICANT ACCUMULATION IS EXPECTED
EAST AND WEST OF THE DIVIDE. CLEARING WILL TAKE PLACE WITH FOG
DEVELOPING TUESDAY NIGHT. INVERSIONS AND POOR SMOKE DISPERSAL ARE
EXPECTED LATE TUESDAY NIGHT AND WEDNESDAY MORNING IN THE BASINS
AND VALLEYS.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING WYZ002-003.

WINTER WEATHER ADVISORY UNTIL 6 PM MDT TUESDAY
WYZ001-012-014-024.

&&

$$

SHORT TERM...C.BAKER
LONG TERM...LAVOIE
AVIATION...C.BAKER
FIRE WEATHER...C.BAKER