Area Forecast Discussion
Issued by NWS Riverton, WY

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FXUS65 KRIW 141731
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1131 AM MDT MON APR 14 2014

.SHORT TERM...MONDAY THROUGH WEDNESDAY NIGHT

THE LAST OF THE SNOW FROM LAST NIGHT WILL BE OUT OF HERE BY
DAYBREAK. AND...WITH HIGH PRESSURE BUILDING OVER THE AREA WE EXPECT
TO HAVE A DRY DAY WITH A GOOD DEAL OF SUNSHINE THAT WILL MIX WITH
SOME MID AND HIGH LEVEL CLOUDS AT TIMES. BUT ALL IN ALL...IT LOOKS
FAIRLY TRANQUIL. WITH THE FRESH SNOW COVER STILL IN SOME AREAS THE
COOLING EFFECT AND ALBEDO WILL KEEP TEMPERATURES BELOW NORMAL FOR
MOST AREAS. WITH THE MOISTURE FROM THE SNOW THERE WILL BE ALSO BE
SOME PATCHY FOG AROUND THIS MORNING. THE WEATHER ALSO LOOKS TO
REMAIN LARGELY QUIET TONIGHT...WHICH IS GOOD FOR THE VIEWING OF THE
ECLIPSE TONIGHT WITH ONLY SOME MID OR HIGH LEVEL CLOUDS EXPECTED.
THE ONLY FLY IN THE OINTMENT THERE WOULD BE FOG BUT THIS LOOKS TO BE
PATCHY AND NOT WIDESPREAD AT THIS TIME.  THE ONE EXCEPTION IS THAT
THERE COULD BE SOME GUSTY WINDS ACROSS NEAR THE WORLDS MOST FAMOUS
CROSSROADS...CLARK WITH A TIGHTENING PRESSURE GRADIENT AND POSSIBLY
MOUNTAIN WAVE DEVELOPMENT. THE SET UP DOES NOT LOOK THAT GREAT...SO
AT THIS TIME WE WILL NOT ISSUE ANY HIGHLIGHTS.

HOWEVER...THE BREAK WILL NOT LAST LONG AS YET ANOTHER SYSTEM MOVES
IN FROM THE NORTHWEST. BOTH THE NAM AND THE GFS ARE FAIRLY SIMILAR
WITH THE TIMING WITH WAITING UNTIL THE AFTERNOON TO BRING ANY
PRECIPITATION IN SO THE MORNING WAS KEPT DRY. WITH FLOW GOING
SOUTHWEST AHEAD OF THE SYSTEM IT WILL BE WARMER THAN TODAY WITH THE
DOWNSLOPING FLOW. IT WILL BECOME BREEZY TO WINDY EAST OF THE DIVIDE
WITH THE PRESSURE GRADIENT TIGHTENING. HOWEVER...THE MODELS HAVE
BACKED OFF ON THE 700 MILLIBAR WINDS A BIT SO HIGH WIND HIGHLIGHTS
SHOULD NOT BE NEEDED. PRECIPITATION WILL SPREAD INTO THE NORTHWEST
TUESDAY AFTERNOON BUT TEMPERATURES SHOULD BE WARM ENOUGH THAT THE
LOWER ELEVATIONS WILL START AS RAIN. WE ALSO KEPT AREAS EAST OF THE
DIVIDE DRY THROUGH THE DAY WITH THE DOWNSLOPING FLOW.

WE STILL EXPECT THE PRECIPITATION TO JUMP THE DIVIDE TUESDAY NIGHT
AS THE FRONT SLIDES SOUTH AND SOME JET ENERGY GETS INVOLVED. BOTH
MODELS ARE ALSO KEYING IN ON NORTHERN PORTIONS OF THE AREA WITH THE
BEST UPPER LEVEL DIVERGENCE. THEREFORE...WE RAISED POPS ACROSS
NORTHERN PORTIONS OF THE AREA. THE POTENTIAL FOR SNOW STILL LOOKS TO
BE A POSSIBILITY LATE AT NIGHT ALTHOUGH AMOUNTS ARE STILL SUSPECT.

UNCERTAINTY THEN RAMPS UP AS WE HEAD INTO WEDNESDAY. IT DOES LOOK TO
BE COLD AND DAMP FOR MOST AREAS. HOWEVER...THE PATTERN LOOKS
UNSETTLED WITH SOME VORT MAXES MOVING THROUGH. THE MODELS VARY
WIDELY ON DETAILS HOWEVER WITH PINPOINTING THE HEAVIER
PRECIPITATION. AT THIS POINT WE MADE FEW CHANGES.


.LONG TERM...THURSDAY THROUGH MONDAY

THERE MAY BE SOME LEFTOVER LIGHT SNOW THURSDAY MORNING EAST OF THE
DIVIDE AS THE WEATHER SYSTEM DEPARTS TO THE SOUTH. WILL HAVE ONLY
ISOLATED SNOW SHOWERS FOR SOME MOUNTAINS FOR THURSDAY AFTERNOON.
DRY WEATHER THURS NIGHT AND FRIDAY. DID PUT IN ISOLATED MOUNTAIN
SHOWERS FRIDAY AFTERNOON OVER NW WY DUE TO LATE DAY CONVECTION. THE
NEXT WEATHER SYSTEM WILL SPREAD LIGHT PRECIP OVER THE WESTERN
MOUNTAINS FRIDAY NIGHT INTO SATURDAY MORNING. THIS SYSTEM PASSES
THROUGH THE STATE SATURDAY WITH AFTERNOON AND EVENING CONVECTIVE
SHOWERS OVER THE MOUNTAINS...ISOLATED SHOWERS AT BEST OVER THE
LOWER ELEVATIONS. DRY LATE SATURDAY NIGHT. SUNDAY LOOKS DRY WITH
POSSIBLE ISOLATED CONVECTION OVER THE SOUTH ZONES AS MOISTURE
LINGERS THERE. WILL NOT ADD ANY SHOWERS THIS FAR OUT AND SEE HOW
THINGS LOOK TONIGHT. NEXT MONDAY LOOKS DRY FOR MOST PLACES.
ISOLATED SHOWERS IN THE NW WY MOUNTAINS MONDAY AFTERNOON AS
MOISTURE MOVES INTO THE AREA PER THE GFS MODEL. THE ECMWF AND GEM
MODELS ARE DRY FOR NOW IN NW WY. AS FOR TEMPS...MILDER THURSDAY
BUT STILL BELOW NORMAL FOR HIGHS. THEN WARMER HIGHS FRIDAY THROUGH
NEXT MONDAY...GETTING BACK TO NORMAL OR EVEN ABOVE NORMAL HIGHS
FOR SUNDAY AND MONDAY.

&&

.AVIATION.../18Z ISSUANCE/

LOW CLOUDS WILL CONTINUE ERODING IN THE UPPER GREEN RIVER BASIN
OVER TO KEMMERER AND THESE CLOUDS SHOULD BE ALL BUT GONE BY 1 PM.
OTHERWISE...VFR THROUGH TONIGHT AND INTO TUESDAY MORNING. W-SW
WINDS WILL INCREASE ALONG THE CODY FOOTHILLS AND THROUGH THE WIND
CORRIDOR FROM VCNTY 50NE KRKS- KCPR. AREAS OF LLWS MAY BE
ENCOUNTERED VCNTY KDUB-KCOD 06Z-12Z TUESDAY. A NEW WEATHER SYSTEM
WILL BRING AN INCREASING CHANCE OF RAIN AND SNOW SHOWERS TO THE
NORTHWEST INCLUDING KJAC AFTER 21Z TUESDAY WITH MOUNTAIN
OBSCURATIONS BECOMING COMMON.

&&

.FIRE WEATHER...

PATCHY LOW STRATUS AND FOG IS EXPECTED TO FORM OVER THE FRESH WET
SNOW COVER IN THE VALLEYS AND BASINS. AFTER AREAS OF MORNING FOG
AND STRATUS...CLEARING IS EXPECTED WITH SLIGHTLY WARMER
TEMPERATURES IN THE AFTERNOON. EXPECT WARMER AND BREEZY TO WINDY
CONDITIONS ON TUESDAY AHEAD OF THE NEXT COLD FRONT THAT WILL
SPREAD RAIN AND SNOW TO NORTHWESTERN WYOMING TUESDAY AFTERNOON.
&&

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

&&

$$

UPDATE...SKRBAC
SHORT TERM...HATTINGS
LONG TERM...AR
AVIATION...AEM
FIRE WEATHER...HATTINGS








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