Hail in Wyoming, September 24, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
250 PM MDT SAT SEP 24 2005

.SHORT TERM...TONIGHT THROUGH TUESDAY
CLOUDY AND COOL OVER ALL BUT THE SOUTH/SOUTHWEST PART OF CWA.
CONVECTION FIRING ALONG AND SOUTHWEST OF THE FRONTAL BOUNDARY. UPPER
TROF SPINNING IN IDAHO AND HAS ELONGATED TODAY. NOSE OF UPPER JET
INTO SRN UTAH NOW AND THIS WILL AID EVENING CONVECTION OVER THE CWA.
STORMS TO BE ELEVATED OVER THE FRONTAL BOUNDARY AS WELL SO HAVE
INCLUDED ISOLD TS IN ALL AREAS. HAVE WENT WITH SCT POPS MOST AREAS
WITH HIGHER VALUES MTS TONIGHT. UPPER TROF SLOWLY MOVES ACROSS WY
SUNDAY. HAVE ADJUSTED POPS FOR TIMING OF TROF. LITTLE WARMER DAY
SUNDAY AS SOME SUNSHINE SHOULD OCCUR MOST AREAS IN THE PM. TROF
DEPARTS SUN EVE WITH CLEARING AND COLD NT. LOWERED MIN TEMPS FOR MON
A.M. WITH FROST A GOOD BET MANY VALLEYS. MONDAY LOOKS DRY AND WARMER
AS WEAK RIDGE MOVES OVER THE AREA. WX SYSTEM PROGD TO DROP SE FROM
CANADA INTO NRN ROCKIES TUE. SOME QUESTION ABOUT UPPER CIRCULATION
AROUND CALIF AND ITS IMPACT TO THE OVERALL WX SCHEME TUE. NAM/GFS/EC
ALL WISH TO BRING IT NE INTO SW U.S. WITH MOISTURE SPREADING INTO THE
STATE. GOING FORECAST FOR MON NT AND TUE WAS LEFT UNCHANGED WITH A
LOW CHANCE OF PCPN TUE OVER MOST AREAS. MILD HIGHS ON TUE WITH BREEZY
AREAS IN THE AFTERNOON.

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...
NOT A LOT OF CHANGES TO EXTENDED FORECAST AT THIS TIME WITH QUITE A
SPREAD ON MEDIUM RANGE GUIDANCE. THE CUT OFF LOW THAT FORMS OFF WEST
COAST OF CA LATE THIS WEEKEND WILL BE MAIN QUESTION AS TO ITS
POSITION AND ASSOCIATED WEATHER BY THE MIDDLE OF WEEK. NORTHERN
STREAM SYSTEM DROPS SOUTHEAST THROUGH AREA TUESDAY FOR CONTINUED RISK
FOR PRECIP. IN RESPONSE TO THIS NORTHERN STREAM SYSTEM...THE GFS ALSO
PULLS CUT OFF LOW NORTHEAST TOWARD AREA THROUGH THURSDAY. THIS IS A
CHANGE FROM PREVIOUS GUIDANCE AND IS NOT SUPPORTED BY ECMWF WHICH
KEEPS UPPER LOW WELL SOUTHWEST OF AREA WITH RIDGING ACROSS WY.
ENSEMBLE GUIDANCE SPLIT BETWEEN THESE SOLUTIONS. HAVE THEREFORE
FOLLOWED ECMWF GUIDANCE AND KEPT FORECAST DRY THROUGH END OF WEEK...
BUT EVOLUTION OF UPPER LOW WILL HAVE TO BE WATCHED ON LATER SHIFTS.
LOW GRADE PRECIP CHANCES INTRODUCED BY SATURDAY WITH DEEPER NORTHERN
STREAM TROUGH EXPECTED TO APPROACH. TEMPERATURES EXPECTED TO BE NOT
TOO FAR FROM NORMAL VALUES THROUGH PERIOD.

 &&

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

&&

SHORT TERM...AR
LONG TERM...FRIEDERS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RIVERTON WY
157 PM MDT SAT SEP 24 2005

WYZ001>020-022>030-251200-
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-
157 PM MDT SAT SEP 24 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL WYOMING.

.DAY ONE...REST OF THIS AFTERNOON AND TONIGHT

SHOWERS AND THUNDERSTORMS WILL OCCUR THE REST OF TODAY AND TONIGHT.
SNOW WILL OCCUR IN THE MOUNTAIN ELEVATIONS ABOVE 8000 FEET WHERE 1
TO 3 INCHES ARE EXPECTED...ESPECIALLY IN AREAS OF THUNDER SNOW.
PEOPLE WITH OUTDOOR INTERESTS SHOULD BE PREPARED FOR WET AND COLD
CONDITIONS THROUGH TONIGHT.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

SOME SHOWERS AND AFTERNOON THUNDERSTORMS WILL BE POSSIBLE SUNDAY IN
CENTRAL WYOMING. THE FAR WEST AND SOUTHWEST PORTION OF THE STATE WILL
BE MOSTLY DRY. ISOLATED AFTERNOON AND EVENING THUNDERSTORMS ARE
POSSIBLE TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO REPORT ANY RAIN OR SNOW AMOUNTS.

TRIW