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000
FXUS65 KRIW 202016
AFDRIW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
216 PM MDT SUN JUL 20 2014

.SHORT TERM...TONIGHT THROUGH MONDAY

A SERIES OF WEAK SHORT WAVE TROUGHS WILL MOVE THROUGH THE WEST
SOUTHWEST FLOW ALOFT BRINGING LIMITED MONSOON MOISTURE INTO WEST
THROUGH SOUTH CENTRAL WYOMING TONIGHT AND MONDAY. THIS WILL HELP
SUPPORT ISOLATED AFTERNOON AND EVENING THUNDERSTORMS WITH STRONG
OUTFLOW WIND GUSTS THIS EVENING AND AGAIN MONDAY AFTERNOON AND
EVENING MAINLY IN SOUTH CENTRAL WYOMING AND OVER THE MOUNTAINS.
THUNDERSTORMS WILL SHIFT MORE INTO THE NORTHERN MOUNTAINS MONDAY
AFTERNOON AS SOME DRYING MOVES INTO THE SOUTH.  CONDITIONS WILL BE
DRY AND BREEZY OUTSIDE OF THE THUNDERSTORM ACTIVITY.

.LONG TERM...MONDAY NIGHT THROUGH SUNDAY

A WEAK NORTHERN STREAM SHORTWAVE WILL TRACK EAST ACROSS THE NORTHERN
ROCKIES AND WILL EXIT THE AREA MONDAY EVENING. THIS FEATURE WILL
COINCIDE WITH A SOUTHERN STREAM VORT LOBE THAT WILL RESULT IN A GOOD
CHANCE OF THUNDERSTORMS ACROSS MAINLY NORTHWEST WYOMING ALONG WITH A
LESSER CHANCE OF STORMS OVER THE BIG HORN MTNS AND THE FAR NORTHERN
TIER OF THE BIG HORN BASIN EARLY MONDAY EVENING. AN ASSOCIATED COOL
FRONT WILL DROP TEMPERATURES A FEW DEGREES TUESDAY BEHIND THIS
EXITING FEATURE. THEN AS A PROMINENT CIRCULATION NOW OVER THE GULF
OF ALASKA TRACKS TO THE PACIFIC NORTHWEST COAST...THE FLOW WILL
INCREASE FROM THE SOUTHWEST AHEAD OF THIS APPROACHING FEATURE
USHERING IN MORE HEAT FOR WEDNESDAY AND THURSDAY WITH HIGHS REACHING
AS HIGH AS THE UPPER 90S IN THE BIG HORN BASIN DURING THIS TIME
FRAME. WITH THE ANTICIPATED HEAT...MIN RH IN THE LOW TO MID TEENS
AND INCREASING SOUTHWEST WINDS...FIRE DANGER WILL LIKELY BE AN
ISSUE ONCE AGAIN. MAINLY ISOLATED THUNDERSTORMS ARE EXPECTED THROUGH
MID WEEK. THEN AS THE AFOREMENTIONED PROMINENT STACKED H7-H3 LOW
TRACKS FROM THE PAC NW THU TO SASK FRIDAY...A TRAILING SHORTWAVE
TROUGH WILL TRACK ACROSS THE REGION THU WITH THE MAIN FLOW VEERING
FROM SOUTHWEST TO WESTERLY SHUNTING ANY REMAINING MEAGER MONSOON
MOISTURE WELL TO OUR SOUTH FOR DRY CONDITIONS FRIDAY THROUGH THE
WEEKEND. TEMPERATURES WILL BE COOLER FOR FRIDAY THROUGH THE WEEKEND
BEHIND THIS MAIN SHORTWAVE.

&&

.AVIATION.../00Z ISSUANCE/

VFR CONDITIONS WILL PREVAIL AT THE AIRPORTS THROUGH 00Z TUESDAY. MAIN
SMOKE PLUMES THAT HAVE BEEN CAUSING SOME LOCALIZED 6SM IN THE
MORNINGS WILL SHIFT NORTH OF THE STATE AS FLOW ALOFT BACKS MORE
TO THE SOUTHWEST. LIMITED MONSOON MOISTURE THAT HAS PUSHED NORTH
INTO SOUTHERN WYOMING AND WILL PUSH NORTHEAST TONIGHT AND MONDAY.
BEST CHANCE FOR ISOLATED SHOWERS AND STORMS WILL BE OVER THE SOUTHWEST
AND SOUTH CENTRAL AREAS AND OVER THE WESTERN MOUNTAINS SHIFTING
INTO THE NORTHERN MOUNTAINS MONDAY AFTERNOON.  INSTABILITY NOT
IMPRESSIVE AND DYNAMICS AND MOISTURE ARE LACKING...SO ANY
CONVECTION WILL BE DEPENDENT UPON DIURNAL HEATING AND OROGRAPHIC LIFT.
WEST SOUTHWEST WIND WILL BLOW 15G30KTS IN THE CORRIDOR FROM KRKS-
KCPR UNTIL 03Z AND AGAIN AFTER 17Z MONDAY.

&&

.FIRE WEATHER...

A RED FLAG WARNING REMAINS IN EFFECT FOR FIRE WEATHER ZONES 279 AND 280
UNTIL 8 PM THIS EVENING...AND AGAIN FROM NOON TO 8 PM MDT ON
MONDAY FOR STRONG DRY WEST SOUTHWEST WINDS AND VERY LOW RELATIVE
HUMIDITY.

A SERIES OF WEAK SHORT WAVE TROUGHS WILL MOVE THROUGH THE WEST
SOUTHWEST FLOW ALOFT BRINGING LIMITED MONSOON MOISTURE INTO WEST
THROUGH SOUTH CENTRAL WYOMING TONIGHT AND MONDAY. THIS WILL HELP
SUPPORT ISOLATED AFTERNOON AND EVENING THUNDERSTORMS WITH STRONG
OUTFLOW WIND GUSTS THIS EVENING AND AGAIN MONDAY AFTERNOON AND
EVENING MAINLY IN SOUTH CENTRAL WYOMING AND OVER THE MOUNTAINS.
CONDITIONS WILL BE DRY AND BREEZY OUTSIDE OF THE THUNDERSTORM
ACTIVITY.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING WYZ279-280.

RED FLAG WARNING FROM NOON TO 8 PM MDT MONDAY WYZ279-280.

&&

$$

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