FNUS75 KRIW 211556
FWSRIW

SPOT FORECAST FOR WIGGINS FORKUNITS4-5...USFS SHF
NATIONAL WEATHER SERVICE RIVERTON WY
956 AM MDT WED APR 21 2010

FORECAST IS BASED ON IGNITION TIME OF 0915 MDT ON APRIL 21.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

.DISCUSSION...A LOW PRESSURE CENTER OVER CALIFORNIA WILL TRACK EAST TO
COLORADO FRIDAY. MOISTURE AND INSTABILITY STREAMING NORTHEAST INTO THE
AREA AHEAD OF THE APPROACHING LOW WILL CREATE A THREAT OF RAIN AND
SNOW SHOWERS AS WELL AS THUNDERSTORMS ACROSS THE FIRE AREA THIS AFTERNOON
THROUGH THURSDAY NIGHT. AS THE LOW PASSES TO THE SOUTH...ACCUMULATING SNOWFALL
IS LIKELY FRIDAY...ESPECIALLY IN THE MORNING.

...THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS...
...HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT...

FORECASTER...LIPSON

.TODAY...
SKY/WEATHER.........CONSIDERABLE HIGH AND MID LEVEL CLOUDS THIS MORNING
                    (80-90 PERCENT). CUMULUS FORMATION BY 1200.
                    RAIN SHOWERS AND ISOLATED THUNDERSTORMS BY 1500 TO 1600
                    IN THE AFTERNOON.
MAX TEMPERATURE.....54-57.
MIN HUMIDITY........37-40 PERCENT.
WIND (20 FT)........UPSLOPE/UPVALLEY 5-9 MPH BECOMING SOUTHEAST
                    AROUND 10 MPH LATE IN THE AFTERNOON. GUSTY AND
                    ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS IN
                    THE AFTERNOON.
RIDGE TOP WINDS.....SOUTHEAST 20 TO 25 MPH.
LAL.................1 UNTIL 1200...THEN 2.
CWR.................30 PERCENT.
HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME
                    DOMINATED FIRE GROWTH.
MIXING HEIGHT.......2000-2900 FT AGL.
TRANSPORT WINDS.....SOUTHEAST 16 TO 22 MPH.
SMOKE DISPERSAL.....POOR TO FAIR (32500-54800 KNOT-FT).

.TONIGHT...
SKY/WEATHER.........CLOUDY (90-100 PERCENT). THUNDERSTORMS LIKELY
                    EARLY IN THE EVENING. RAIN SHOWERS LIKELY IN
                    THE EVENING...THEN SNOW SHOWERS LIKELY AFTER
                    MIDNIGHT.
MIN TEMPERATURE.....32-35.
MAX HUMIDITY........88-91 PERCENT.
WIND (20 FT)........EAST WINDS 8 TO 10 MPH UNTIL EARLY MORNING
                    BECOMING DOWNSLOPE/DOWNVALLEY 4-7 MPH. GUSTY
                    AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS
                    EARLY IN THE EVENING.
RIDGE TOP WINDS.....SOUTHEAST 30 TO 35 MPH DECREASING TO AROUND 20
                    MPH EARLY IN THE MORNING.
LAL.................2 UNTIL 2100...THEN 1.
CWR.................30 PERCENT.
HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME
                    DOMINATED FIRE GROWTH.
MIXING HEIGHT.......2200 FT AGL.
TRANSPORT WINDS.....EAST 15 TO 21 MPH.
SMOKE DISPERSAL.....POOR TO FAIR (30300-41400 KNOT-FT).

.THURSDAY...
SKY/WEATHER.........CLOUDY (95-100 PERCENT). SNOW SHOWERS LIKELY IN
                    THE MORNING. RAIN SHOWERS LIKELY THROUGH THE
                    DAY.
MAX TEMPERATURE.....AROUND 50.
MIN HUMIDITY........48-51 PERCENT.
WIND (20 FT)........UPSLOPE/UPVALLEY 5-9 MPH. GUSTS UP TO 15 MPH.
RIDGE TOP WINDS.....EAST 20 TO 25 MPH.
LAL.................1.
CWR.................100 PERCENT.
HAINES INDEX........2 OR VERY LOW POTENTIAL FOR LARGE PLUME
                    DOMINATED FIRE GROWTH.
MIXING HEIGHT.......2200-3200 FT AGL.
TRANSPORT WINDS.....EAST 16 TO 20 MPH.
SMOKE DISPERSAL.....POOR TO FAIR (32700-48300 KNOT-FT).

.FORECAST DAYS 3 THROUGH 5...
.THURSDAY NIGHT...SHOWERS LIKELY IN THE EVENING...THEN SNOW
SHOWERS LIKELY AFTER MIDNIGHT. LOWS IN THE UPPER 20S. NORTHWEST
WINDS AROUND 12 MPH.
.FRIDAY...COLDER. CLOUDY WITH SNOW LIKELY. LOWS IN THE MID 20S.
HIGHS IN THE MID 30S. NORTH WINDS AROUND 13 MPH.
.SATURDAY...PARTLY CLOUDY. SLIGHT CHANCE OF RAIN AND SNOW. LOWS
IN THE MID 20S. HIGHS IN THE LOWER 40S. WINDS GENERALLY LESS THAN
10 MPH.
.SUNDAY...MOSTLY CLOUDY WITH CHANCE OF SHOWERS AND SNOW SHOWERS.
LOWS IN THE MID 20S. HIGHS IN THE UPPER 30S. WINDS GENERALLY LESS
THAN 10 MPH.

$$

FORECASTER...LIPSON
REQUESTED BY...SLAGOWSKI
REASON FOR REQUEST...PRESCRIBED
.TAG 20100421.WIGGI.02/RIW