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FXUS65 KRIW 141730
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
1130 AM MDT FRI JUN 14 2013

.SHORT TERM...FRIDAY THROUGH SUNDAY NIGHT

IT FINALLY LOOKS LIKE THE LAST FEW DAYS OF ACTIVE WEATHER WILL BE
COMING TO AN END. AT 2 AM...ONE LAST AREA OF SHOWERS AND EMBEDDED
THUNDER IS DEVELOPING ACROSS THE BIG HORN BASIN AS THE LAST
SHORTWAVE SWINGS TO THE AREA BUT THESE SHOULD BE OUT OF THE AREA BY
DAYBREAK.  DRIER AIR IS MOVING IN FROM THE SOUTHWEST WITH THE MODELS
SHOWING PRECIPITABLE WATER VALUES FALLING TO UNDER 0.4 INCHES FOR
ALL AREAS. WE HAVE LEFT A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS
ACROSS PORTIONS OF YELLOWSTONE WHERE A FLATTENING TROUGH MAY GET
CLOSE ENOUGH TO CREATE ENOUGH INSTABILITY FOR ISOLATED CONVECTION.
ELSEWHERE...EXPECT A DRY DAY WITH SUNSHINE AND ONLY A FEW PASSING
CLOUDS. THERE WILL BE A GUSTY WESTERLY BREEZY BEHIND THE FRONT AS
WELL FOR MOST AREAS AS WELL ALTHOUGH NO HIGHS WINDS ARE EXPECTED.
HIGH TEMPERATURES SHOULD RUN AROUND 10 DEGREES COOLER THAN
YESTERDAY.

TEMPERATURES SHOULD BEGIN A SLOW WARMING TREND ONCE AGAIN FOR
SATURDAY AS THE TROUGH MOVES AND ANOTHER RIDGE BUILDS FROM THE WEST.
A BIT MORE MOISTURE WILL BEGIN TO MOVE BACK IN AS WELL. A COUPLE OF
MODELS SHOW ISOLATED CONVECTION ACROSS THE FAR SOUTHERN AND
SOUTHEASTERN PORTIONS OF THE WARNING AREA BUT THE CHANCE LOOKS LOW
ENOUGH SO WE HAVE KEPT THE FORECAST DRY AT THIS TIME.

RIDGING LOOKS TO REMAIN IN CONTROL OF THE WEATHER FOR SUNDAY AS WELL
ALTHOUGH THIS IS LOOKING MORE LIKE A DIRTY RIDGE WITH MORE MOISTURE
MOVING BACK INTO THE AREA. AS A RESULT WE HAVE ADDED SOME AFTERNOON
AND EVENING POPS ALTHOUGH FOR NOW WE HAVE KEPT THEM CONFINED TO THE
HIGHER ELEVATIONS WITH THE HIGHER ELEVATION HEAT SOURCE.

.LONG TERM...MONDAY THROUGH FRIDAY

NO SIGNIFICANT CHANGES TO THIS PERIOD THIS MORNING.  THE UPPER AIR
PATTERN FEATURES A RIDGE OF HIGH PRESSURE OVER THE AREA MONDAY WITH
UPPER LOW OFF THE NW COAST.  THIS PATTERN WILL SHOW SLOW PROGRESSION
THROUGH THE PERIOD WITH THE UPPER LOW FORECAST TO MOVE INTO THE NW
U.S. ON WEDNESDAY...AND LIFT INTO WESTERN MONTANA THURSDAY PER GFS
WITH THE ECMWF A BIT SLOWER AND FURTHER WEST WITH THIS TRACK.

SURFACE HIGH PRESSURE OVER THE NORTHERN HIGH PLAINS WILL SLIDE
SOUTHEAST ON MONDAY AND TUESDAY AND WILL BRING AN E TO SE FLOW AND
BETTER MOISTURE/INSTABILITY ACROSS NORTHERN AND EASTERN WYOMING FOR
ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS.  A DRIER
AIRMASS WILL PREVAIL ACROSS THE SOUTH AND WEST.

MOST OF WYOMING WILL BE UNDER THE INFLUENCE OF THE DRY WARM SECTOR
AHEAD OF THE UPPER LOW ON WEDNESDAY WITH A COLD FRONT PUSHING INTO
THE NW ON THURSDAY.  WARM AND BREEZY TO WINDY
CONDITIONS...HEIGHTENED FIRE WEATHER CONCERNS WILL PREVAIL ON
WEDNESDAY.  SLIGHT CHANCES OF THUNDERSTORMS WILL REMAIN ACROSS THE
NORTH WEDNESDAY AND THURSDAY.

COOLER CONDITIONS WILL PREVAIL ACROSS THE AREA ON FRIDAY WITH MAINLY
DRY CONDITIONS.

&&

.AVIATION.../18Z ISSUANCE/

MOSTLY DRY CONDITIONS ACROSS THE STATE AND TERMINALS TODAY WITH
GENERALLY VFR CONDITIONS. THOUGH SHOWER ACTIVITY IS UNLIKELY OUTSIDE
OF EXTREME NORTHWESTERN WYOMING...GUSTY SOUTHWEST TO WEST
WINDS HAVE DEVELOPED ACROSS THE FORECAST AREA AND WILL PERSIST INTO
THE EARLY EVENING PERIOD BEFORE RELAXING AS THE REGION IS
SANDWICHED BETWEEN AN EXITING SURFACE LOW AND HIGH PRESSURE TO THE
WEST. AS HIGH PRESSURE TAKES OVER SATURDAY...WINDS WILL REMAIN
RELAXED THROUGH SATURDAY.

&&

.FIRE WEATHER...

EXPECT A MORE STABLE DAY TODAY WITH ANY SHOWERS OR THUNDERSTORMS
ENDING BY SUNRISE. TEMPERATURES WILL AVERAGE 10 DEGREES COOLER THAN
YESTERDAY. A GUSTY WESTERLY BREEZE WILL BLOW ACROSS MUCH OF THE
AREA WITH RELATIVE HUMIDITY FALLING TO UNDER 15 PERCENT ACROSS
MUCH OF THE CENTRAL AND SOUTHERN ZONES. MAINLY DRY WEATHER WITH
LESS WIND IS EXPECTED FOR SATURDAY AS RIDGING BEGINS TO REBUILD
ACROSS THE AREA. INCREASED MOISTURE MAY BRING ISOLATED SHOWERS AND
THUNDERSTORMS FOR SUNDAY AFTERNOON AND EVENING. &&

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

$$

SHORT TERM...HATTINGS
LONG TERM...AEM
AVIATION...BRANHAM
FIRE WEATHER...HATTINGS