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000
FXUS65 KRIW 162054
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
254 PM MDT WED APR 16 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY

NICE CONVECTIVE ACTIVITY THIS AFTERNOON ALONG THE EASTERN SLOPES
OF THE BIGHORN MOUNTAINS SOUTH INTO NATRONA COUNTY. THE SHOWERS
HAVE BEEN REDUCING VISIBILITIES DOWN TO 1SM AT KCPR AND POSSIBLY
ON AREA ROADWAYS. SIMILAR CONDITIONS EVIDENT ALONG EAST SLOPES OF
ABSAROKAS - WEST PART OF THE BIG HORN BASIN. CERTAINLY COOLER AND
MOISTER EAST OF THE DIVIDE...WITH BREEZY DRIER CONDITIONS ACROSS
SOUTHWEST WYOMING. EXPECTING THE WEAK CONVECTIVE ACTIVITY TO
CONTINUE INTO THE EARLY EVENING HOURS BEFORE DISSIPATING. MOST LIKELY
AREAS FOR THE SHOWERS ARE ACROSS THE NORTHERN BIG HORN
BASIN...OVER TO JOHNSON COUNTY. OVERALL CLOUDINESS IS ALSO EXPECTED
TO CONTINUE OVERNIGHT WITH SLIGHTLY DESTABILIZED MID LAYERS.

VERY SHORTWAVE RIDGE LOOKS TO MOVE OVER THE FORECAST AREA ON
THURSDAY. WITH 700MB TEMPS WARMING BACK UP TO -2C TO 2C...AFTERNOON
TEMPERATURES WILL BE ABOUT 10 DEGREES WARMER THAN WEDNESDAY.
ANOTHER SHORTWAVE TROUGH MOVES INTO THE PACIFIC NORTHWEST ON
THURSDAY.  AS LEE SIDE TROUGH BEGINS TO BUILD IN MONTANA AND NE
WY...SOUTHWEST WIND WILL INCREASE DURING THE AFTERNOON AND EVENING
FROM SW TO CENTRAL WYOMING.

.LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY

PROGRESSIVE ATMOSPHERIC PATTERN DURING THIS EXTENDED PERIOD. NO
MAJOR WEATHER SYSTEMS EXPECTED THROUGH TUESDAY WITH AT OR ABOVE
NORMAL TEMPERATURES FOR WEST CENTRAL WYOMING. FRIDAY NIGHT AND
SATURDAY WILL HAVE NEAR NORMAL TEMPERATURES BEHIND A COLD FRONT.

ABOVE NORMAL TEMPERATURES THEN LOOK VERY LIKELY MONDAY AND TUESDAY
AHEAD OF AN INCOMING WEST COAST TROUGH. COULD HAVE SOME DECENT
SNOWMELT IN THE WYOMING HIGH COUNTRY THESE TWO DAYS WITH WARMING AT
BOTH THE SURFACE AND ALOFT. PATTERN ALSO SUPPORTS BREEZY CONDITIONS.

AFOREMENTIONED TROUGH THEN APPROACHES ROCKIES BY WEDNESDAY OF NEXT
WEEK. TOO EARLY TO TELL HOW THIS SYSTEM WILL BEHAVE...BUT COULD BE
MIXED BAG OF WEATHER ACROSS WEST CENTRAL WYOMING DURING THE DAY.
WILL MONITOR NEXT FEW MODEL RUNS...ESPECIALLY WITH RESPECT TO TIMING.

&&

.AVIATION.../18Z ISSUANCE/

THE OVERNIGHT DISTURBANCE IS MOVING SOUTHEAST OUT OF WYOMING
TODAY...WITH LEFTOVER MOISTURE AND NORTHWEST FLOW...MAINLY IMPACTING
EASTERN AND CENTRAL WYOMING.  MVFR CONDITIONS WITH LOWERED CEILINGS
EXPECTED THIS AFTERNOON FROM KCPR TO KBYG WITH MOUNTAIN OBSCURATIONS
THROUGHOUT.  VFR CONDITIONS ARE EXPECTED ELSEWHERE THROUGHOUT
WESTERN AND CENTRAL WYOMING.

ISOLATED SHOWERS ARE EXPECTED OVER THE MOUNTAINS OF NORTHERN WYOMING
THIS AFTERNOON BEFORE DISSIPATING EARLY THIS EVENING. WIND SPEEDS
ARE LIKELY AROUND 8-10 KNOTS WITH SOME GUSTS IN THE NORTHWEST FLOW
AROUND 20 KNOTS.  HIGH PRESSURE WILL MOVE IN THURSDAY...WITH PARTLY
CLOUDY SKIES AND INCREASING SOUTHWEST WIND ACROSS SOUTHERN AND
CENTRAL WYOMING IN THE AFTERNOON AND EARLY EVENING.

&&

.FIRE WEATHER...

RELATIVELY COOL AND MOIST CONDITIONS EAST OF THE DIVIDE LATE THIS
AFTERNOON AND EVENING DUE TO BACKSIDE OF DEPARTING LOW PRESSURE
SYSTEM. ISOLATED SHOW AND RAIN SHOWERS...ESPECIALLY IN JOHNSON AND
NATRONA COUNTIES AS WELL AS AROUND THE BIGHORN MOUNTAINS AND EAST
SLOPES OF THE ABSAROKAS...WILL DECREASE IN THE EVENING HOURS.  SW
WY WILL BE SOMEWHAT WARMER AND DRIER THIS EVENING WITH HUMIDITY
VALUES REBOUNDING FROM THE UPPER TEENS.

THURSDAY WILL SEE HIGH PRESSURE MOVING OVER THE REGION. RESULT IS
AFTERNOON TEMPERATURES 10-12 DEGREES WARMER THAN WEDNESDAY. MIN RH
VALUES WILL DROP AS WELL INTO THE 20S AND LOW 30S...ESPECIALLY IN
NORTHERN AND CENTRAL WYOMING. WIND WILL BE RELATIVELY LIGHT
OVERNIGHT AND INTO THURSDAY MORNING BEFORE PICKING UP FROM THE
SOUTHWEST THURSDAY AFTERNOON...ESPECIALLY ACROSS SOUTHERN AND
CENTRAL WYOMING.

FRIDAY WILL SEE INCREASED CLOUDINESS FROM THE WEST AS SHOWERS ARE
EXPECTED ACROSS NORTHWEST WYOMING BY MID DAY. EVEN MORE WARMING
EAST OF THE DIVIDE AND IN SOUTHERN WYOMING AHEAD OF A WEAK FRONT
THAT WILL SAG ACROSS SW TO NE WY BY FRIDAY EVENING.

&&

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

&&

$$

SHORT TERM...MCDONALD
LONG TERM...KPL
AVIATION...MCDONALD
FIRE WEATHER...MCDONALD