Red Flag Warning 2, NWS Riverton, WY

000 
WWUS85 KRIW 100259
RFWRIW

RED FLAG WARNING
NATIONAL WEATHER SERVICE RIVERTON WY
859 PM MDT MON JUL 9 2007


WYZ277-279-100400-
/O.EXP.KRIW.FW.W.0002.000000T0000Z-070710T0300Z/
LINCOLN AND UINTA COUNTIES / LOWER ELEVATIONS-
SWEETWATER COUNTY / ROCK SPRINGS BLM / FLAMING GORGE NRA-
859 PM MDT MON JUL 9 2007

...RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING...

THE RED FLAG WARNING WILL EXPIRE AT 9 PM MDT THIS EVENING. 

AS THE EVENING HOURS CONTINUE...CRITICAL FIRE WEATHER CONDITIONS HAVE
DECREASED...THUS THE RED FLAG WARNING HAS BEEN ALLOWED TO EXPIRE.
RELATIVE HUMIDITY VALUES ARE MOSTLY ABOVE 15 PERCENT...AND WINDS
GUSTS HAVE DROPPED BELOW 25 MPH. WIND GUSTS OF 20 TO 25 MPH MAY BE
EXPERIENCED UNTIL MIDNIGHT...AND A WIND SHIFT TO THE NORTHEAST IS
EXPECTED FROM MIDNIGHT TO 3 AM MDT...AS A COOL FRONT PUSHES INTO
SOUTHERN WYOMING.

$$

MCDONALD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
302 AM MDT MON JUL 9 2007

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT

SHORTWAVE MOVING ACROSS THE SOUTHERN CANADIAN PLAINS TODAY IS
HANDLED SIMILARLY BY THE 00Z RUNS OF THE GFS AND NAM. BOTH MODELS
SHOW A SFC COLD FRONT PUSHING SOUTHWARD INTO NORTHEASTERN WY LATE
THIS AFTERNOON. SLIGHT H5 RIDGING AHEAD OF THE TROUGH IS EXPECTED
TO ALLOW THE STRONG UPPER HIGH OVER THE SOUTHWEST U.S. TO RIDGE
SLIGHTLY TO THE NORTH TODAY. GFS THERMAL ADVECTION AT H7 AHEAD OF
THE TROUGH APPEARS TO BE A BIT STRONG...BUT WEIGHTED HIGH
TEMPERATURE FORECAST TOWARD THE WARMER GFS SOLUTION. 15 TO 17 C
TEMPERATURES AT H7 ACROSS THE CENTRAL AND SOUTHERN WY WILL RESULT
IN HIGHS IN THE UPPER 80S TO MID 90S IN THE LOWER ELEVATIONS. GFS
INDICATES THAT DRIER AIR IN THE BOUNDARY LAYER WILL MOVE ACROSS WY
FROM THE WEST RAPIDLY THIS AFTERNOON...BUT THE NAM SOLUTION HOLDS
ONTO LOW LEVEL MOISTURE EAST OF THE ABSAROKA AND WIND RIVER RANGES
THIS AFTERNOON AND EVENING AHEAD OF THE SFC COLD FRONT. PREFER THE
NAM SOLUTION IN THIS CASE...AS MODELS TEND TO SCOUR OUT LOW LEVEL
MOISTURE TOO QUICKLY FROM WEST TO EAST IN THIS PATTERN. NAM
EXTENDS THETA-E RIDGE THIS AFTERNOON AND EVENING WEST INTO THE
WIND RIVER BASIN AND BIGHORN BASIN WITH LIFTED INDICES LESS THAN
MINUS 1 C. INCLUDED ISOLATED SHOWERS AND THUNDERSTORMS IN THESE
BASINS AND POINTS TO THE EAST...EXCEPT FOR THE BIGHORN RANGE AND
JOHNSON COUNTY...WHERE SCATTERED SHOWERS AND THUNDERSTORMS ARE
EXPECTED WITH LOW LEVEL CONVERGENCE ALONG THE COLD FRONT.

GFS AND NAM IN FAIRLY GOOD AGREEMENT TUESDAY IN PUSHING THE COLD
FRONT THROUGH THE CWA...AS THE SHORTWAVE TO THE EAST DIGS
SOUTHWARD INTO THE UPPER MIDWEST. STRONG CAA BEHIND THE FRONT WILL
PRODUCE SIGNIFICANT COOLING WITH AFTERNOON H7 TEMPERATURES FALLING
INTO THE 8 TO 14 C RANGE FROM NORTHEAST TO SOUTHWEST ACROSS THE
CWA. HIGHS ACROSS THE NORTHEASTERN CWA WILL ONLY REACH THE MID TO
UPPER 70S IN THE LOWER ELEVATIONS WITH HIGHS TO THE SOUTH AND WEST
ONLY IN THE UPPER 70S TO MID 80S. ANY AFTERNOON AND EVENING
CONVECTION SHOULD BE CONFINED TO THE HIGHER ELEVATIONS WEST OF THE
DIVIDE TUESDAY. LEANED TOWARD THE COOLER NAM SOLUTION WEDNESDAY
GIVEN NORTHWEST FLOW ALOFT AND THE DEEPENING TROUGH IN THE MIDWEST.
STABLE AIRMASS IN PLACE ACROSS THE REGION WEDNESDAY SHOULD LIMIT
ANY ISOLATED CONVECTION TO THE HIGHER ELEVATIONS.

.LONG TERM...THURSDAY THROUGH MONDAY
UPPER RIDGE...CURRENTLY OVER EASTERN PACIFIC NEAR 140W...TO MOVE
INTO WESTERN CANADA AND BECOME FULLY PHASED WITH GREAT BASIN UPPER HIGH
BY THURSDAY. THIS HIGH AMPLITUDE RIDGE TO DOMINATE THE WEATHER
THROUGH THIS EXTENDED PERIOD. COLD AIRMASS EAST OF THE DIVIDE
MIDWEEK TO GRADUALLY MODIFY LATE IN THE WEEK INTO THE WEEKEND. GFS
SHOWS A REINFORCING PUSH TO COLD FRONT FRIDAY AS CLIPPER SYSTEM
DIVES INTO THE NORTHERN PLAINS SO TEMPERATURES TO REMAIN NEAR OR
SLIGHTLY ABOVE NORMAL EAST OF THE DIVIDE THROUGH FRIDAY WITH ABOVE
NORMAL TEMPERATURES OUT WEST. INSTABILITY AND LIMITED MOISTURE
WILL RESULT IN ISOLATED THUNDERSTORMS MAINLY WEST OF THE DIVIDE
THURSDAY AND FRIDAY. UPPER RIDGE TO BROADEN AND PROGRESS SLIGHTLY
EASTWARD OVER THE WEEKEND BRINGING HOT SUMMER
TEMPERATURES...MOSTLY IN THE UPPER 80S AND 90S IN THE LOWER
ELEVATIONS SUNDAY AND MONDAY. SLIGHT CHANCES OF THUNDERSTORMS WILL
REMAIN MAINLY OVER THE WESTERN MOUNTAINS AND FAVORED CONVERGENCE
REGIONS IN LIGHT UPVALLEY/UPSLOPE FLOW DURING MAX HEATING.
THUS...AFTER SOME RELIEF FROM THE HEAT DURING THE WORKWEEK A
RETURN TO MAINLY DRY AND HOT WEATHER...ALONG WITH INCREASED FIRE
DANGER RETURN OVER THE WEEKEND.

&&

.AVIATION...
ISOLATED AFTERNOON AND EVENING THUNDERSTORMS ARE POSSIBLE
FROM NEAR THE COD TAF SITE SOUTHEAST TO WRL AND CPR AS
A COLD FRONT SLIDES SOUTH ACROSS THIS AREA. THE WESTERN
TAF SITES FROM JACKSON SOUTH TO ROCK SPRINGS SHOULD BE DRY.
GUSTY NORTH WINDS WILL OCCUR BEHIND THE COLD FRONT WITH
GUSTY WEST TO NORTHWEST WINDS AT THE BPI...PNA AND RKS
TAF SITES IN THE AFTERNOON AND EARLY EVENING. VFR CONDITIONS
WILL DOMINATE WITH ONLY LOCAL MVFR CONDITIONS AROUND THE
ISOLATED LATE DAY THUNDERSTORMS.

&&

.FIRE WEATHER...

LOW LEVEL MOISTURE WILL LINGER ACROSS THE AREA FROM THE WIND RIVER
BASIN AND BIGHORN BASIN TO EASTERN WYOMING. RELATIVELY STRONG
DAYTIME HEATING AND AN APPROACHING COLD FRONT WILL GENERATE
ISOLATED AFTERNOON AND EVENING THUNDERSTORMS ACROSS THIS AREA.
THESE THUNDERSTORMS WILL AGAIN PRODUCE FREQUENT LIGHTNING...STRONG
WIND GUSTS AND SMALL HAIL. A FEW STORMS COULD BECOME SEVERE THIS
AFTERNOON AND EVENING. WINDS WILL REMAIN LIGHT TODAY...LESS THAN
15 MPH WITH A FEW GUSTS UP TO 20 MPH POSSIBLE ACROSS SOUTHERN WY
THIS AFTERNOON.

THE COLD FRONT WILL MOVE SOUTH OF THE REGION MONDAY NIGHT AND TUESDAY.
MUCH COOLER AIR WILL MOVE INTO THE AREA TUESDAY WITH HIGHER
MINIMUM RELATIVE HUMIDITIES EXPECTED ACROSS THE FIRE WEATHER
DISTRICT. RELATIVE HUMIDITIES SHOULD RECOVER VERY WELL TUESDAY
NIGHT WITH LIGHT WINDS AND MOSTLY CLEAR SKIES AFTER MIDNIGHT.
SLIGHTLY DRIER AND WARMER AIR WILL MOVE NORTHWARD ACROSS THE
REGION WEDNESDAY...BUT MINIMUM RELATIVE HUMIDITIES WILL STILL
REMAIN IN THE MID TEENS TO UPPER 20S IN THE LOWER ELEVATIONS.
THUNDERSTORMS ACTIVITY WILL BE ISOLATED AT BEST WITH A MUCH MORE
STABLE AIRMASS ACROSS WYOMING.

&&

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

SHORT TERM...SMITH
LONG TERM...AEM
AVIATION...SKRBAC
FIRE WEATHER...SMITH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RIVERTON WY
500 AM MDT MON JUL 9 2007

WYZ001>020-022>030-101100-
ABSAROKA MOUNTAINS-BIGHORN MOUNTAINS SOUTHEAST-
BIGHORN MOUNTAINS WEST-CASPER MOUNTAIN-CODY FOOTHILLS-
EAST SWEETWATER COUNTY-FLAMING GORGE-
GREEN MOUNTAINS AND RATTLESNAKE RANGE-JACKSON HOLE-LANDER FOOTHILLS-
NATRONA COUNTY LOWER ELEVATIONS-NORTH BIG HORN BASIN-
NORTHEAST JOHNSON COUNTY-OWL CREEK AND BRIDGER MOUNTAINS-
ROCK SPRINGS AND GREEN RIVER-SALT RIVER AND WYOMING RANGES-
SOUTH LINCOLN COUNTY-SOUTHEAST BIG HORN BASIN-
SOUTHEAST JOHNSON COUNTY-SOUTHWEST BIG HORN BASIN-STAR VALLEY-
TETON AND GROS VENTRE MOUNTAINS-UPPER GREEN RIVER BASIN-
UPPER GREEN RIVER BASIN FOOTHILLS-UPPER WIND RIVER BASIN-
WIND RIVER BASIN-WIND RIVER MOUNTAINS EAST-WIND RIVER MOUNTAINS WEST-
YELLOWSTONE NATIONAL PARK-
500 AM MDT MON JUL 9 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING.

.DAY ONE...TODAY AND TONIGHT

ISOLATED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED
EAST OF THE CONTINENTAL DIVIDE THIS AFTERNOON AND EVENING. THE MAIN
HAZARDS WITH THESE STORMS WILL BE STRONG TO SEVERE WIND GUSTS...
LIGHTNING...HAIL AND LOCALLY HEAVY RAINFALL.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS IS EXPECTED
MAINLY WEST OF THE DIVIDE WEDNESDAY THROUGH SUNDAY. THE MAIN
HAZARDS WITH THESE STORMS WILL BE LIGHTNING AND STRONG WIND GUSTS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY AND TONIGHT.  SPOTTERS
ARE REQUESTED TO REPORT ANY STRONG WIND GUSTS OR WIND DAMAGE TO THE
WEATHER OFFICE IMMEDIATELY AT 1-800-211-1448.

TRIW