Wildfire in Wyoming, August 25 to 28, 2002

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RIVERTON WY
128 PM MDT SUN AUG 25 2002

THE 18Z SFC CHART PLACES LOW PRESSURE OVER NE WY INTO MT AND HIGH
PRESSURE OVER WRN WY. WATER VAPOR IMAGERY LOOP SHOWS THE RIDGE OVER
THE ROCKIES WITH THE UPPER TROUGH STRETCHED ACROSS SOUTHERN CAN INTO
THE PAC NW. VIS SAT SHOWS JUST A FEW CU OVER THE MTNS.

THE UPPER TROUGH OVER SRN CAN RE-ESTABILISHES ITSELF OVER THE GREAT
BASIN BY MON NIGHT AND CONTINUES THROUGH THU. UNTIL THEN...THE
CURRENT RIDGE WILL BRING DRY WX TO MOST OF THE FA WITH EXCEPTION OF
SOME ISOLD EVE -TSRA OVER THE FAR NRN FA TONIGHT AND AGAIN MON
AFT/EVE. A COLD FRONT WILL PUSH SOUTH INTO THE FA MON NIGHT AND TUE.
UPSLOPE WIND WILL BRING CLOUDS AND COOLER TEMPS EAST OF THE DIV
TUE/WED. ENERGY EJECTED OUT OF THE TROUGH TO THE WEST WILL POP SOME
-TSRA OVER THE WRN MTNS TUE AFT/EVE WITH A REPEAT ON WED. THESE
STORMS WILL THEN DRIFT ACROSS THE BASINS DURING THE EVE BOTH DAYS.
THE AVN MODEL CLOSES THE LOW OVER ID ON TUE BUT WILL LEAN TOWARD THE
OPEN TROUGH IDEA OF THE ETA WHICH IS IN KEEPING WITH THE CURRENT
FCST OF LOWER POPS.

IN THE EXTENDED...CURRENT FCST ON TRACK WITH A SLIGHT CHANCE OF
-RW/-TSRA THU. THE RIDGE BUILD IN ON FRI BUT A TROUGH IN THE NRN
STREAM MOVES THROUGH SAT PM FOR ANOTHER SLIGHT CHANCE. A RIDGE
BUILDS BACK IN SUN. TEMPS CHG LITTLE THROUGH THE PERIOD.

.RIW...NONE.

FS