FNUS75 KRIW 201745
FWSRIW

SPOT FORECAST FOR HAYFIELDS RESTORATION MGT UNIT...NPS GTP
NATIONAL WEATHER SERVICE RIVERTON WY
1145 AM MDT TUE APR 20 2010

FORECAST IS BASED ON IGNITION TIME OF 1330 MDT ON APRIL 20.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

.DISCUSSION...
ATMOSPHERIC INSTABILITY WILL BE SUFFICIENT TO SUPPORT ISOLATED RAIN
SHOWERS LATE THIS AFTERNOON AND EVENING. A RIDGE OF HIGH PRESSURE
OVER THE REGION WILL KEEP WINDS LESS THAN 10 MPH THROUGH TONIGHT.
LOW PRESSURE OFF THE CALIFORNIA COAST WILL TRACK INTO SOUTHERN NEVADA
BY WEDNESDAY AFTERNOON. MOIST SOUTHERLY FLOW AHEAD OF THIS SYSTEM WILL
GENERATE MORE SHOWERS AND THUNDERSTORMS WEDNESDAY AFTERNOON AND
EVENING. EXPECT COOLER AND WETTER CONDITIONS THURSDAY AND FRIDAY.

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

FORECASTER...JONES

.TODAY...
SKY/WEATHER.........MOSTLY SUNNY (15-25 PERCENT) THEN BECOMING
                    PARTLY CLOUDY (35-45 PERCENT) AFTER 1300.
MAX TEMPERATURE.....66-69.
MIN HUMIDITY........15-19 PERCENT.
WIND (20 FT)........SOUTHEAST 4 TO 8 MPH.
RIDGE TOP WINDS.....SOUTHEAST 10 TO 15 MPH.
LAL.................1.
CWR.................LESS THAN 5 PERCENT.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
                    FIRE GROWTH.
MIXING HEIGHT.......INCREASING TO AROUND 9000 FT AGL BY 1500.
TRANSPORT WINDS.....SOUTH TO SOUTHEAST 10 TO 15 MPH.
SMOKE DISPERSAL.....BECOMING GOOD TO VERY GOOD BY 1400.

.TONIGHT...
SKY/WEATHER.........PARTLY CLOUDY (50-60 PERCENT) THEN BECOMING
                    MOSTLY CLOUDY (70-80 PERCENT). ISOLATED SHOWERS
                    RAIN SHOWERS...BECOMING SCATTERED AFTER 0400.
MIN TEMPERATURE.....32-35.
MAX HUMIDITY........71-76 PERCENT.
WIND (20 FT)........BECOMING NORTH 4 TO 7 MPH BY 1930. GUSTY AND
                    ERRATIC WINDS EXPECTED WITH SHOWERS UNTIL 2200.
RIDGE TOP WINDS.....SOUTHEAST 10 TO 15 MPH.
LAL.................1.
CWR.................LESS THAN 5 PERCENT.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
                    FIRE GROWTH.
MIXING HEIGHT.......DECREASING TO LESS THAN 2000 FT AGL BY 2100.
TRANSPORT WINDS.....BECOMING NORTH 4 TO 8 MPH BY 2000.
SMOKE DISPERSAL.....DECREASING TO POOR BY 2000.

.WEDNESDAY...
SKY/WEATHER.........MOSTLY CLOUDY (60-70 PERCENT). ISOLATED RAIN SHOWERS
                    IN THE MORNING...THEN SCATTERED RAIN SHOWERS
                    AND ISOLATED THUNDERSTORMS AFTER 1300.
MAX TEMPERATURE.....60-63.
MIN HUMIDITY........30-33 PERCENT.
WIND (20 FT)........NORTH 3 TO 6 MPH UNTIL 0900...THEN BECOMING
                    SOUTHEAST AROUND 12 MPH BETWEEN 1100 AND 1300.
                    GUSTY AND ERRATIC WINDS EXPECTED NEAR THUNDERSTORMS
                    IN THE AFTERNOON.
RIDGE TOP WINDS.....SOUTHEAST 15 TO 20 MPH.
LAL.................1 UNTIL 1300...THEN 2.
CWR.................5 PERCENT.
HAINES INDEX........3 OR VERY LOW POTENTIAL FOR LARGE PLUME
                    DOMINATED FIRE GROWTH.
MIXING HEIGHT.......2000 FT AGL UNTIL 0900...THEN GRADUALLY RISING
                    TO AROUND 7000 FT AGL BY 1400.
TRANSPORT WINDS.....NORTH 4 TO 7 MPH UNTIL 1000...THEN BECOMING
                    SOUTHEAST 15 TO 25 MPH BY 1400.
SMOKE DISPERSAL.....POOR UNTIL 0900...THEN BECOMING VERY GOOD BY 1400.

.FORECAST DAYS 3 THROUGH 5...
.WEDNESDAY NIGHT...CLOUDY WITH SCATTERED SHOWERS. LOWS IN THE
UPPER 30S. WINDS GENERALLY LESS THAN 10 MPH.
.THURSDAY...COOLER. CLOUDY WITH SCATTERED SHOWERS AND CHANCE OF
RAIN AND SNOW SHOWERS. LOWS IN THE UPPER 20S. HIGHS IN THE UPPER 40S.
WINDS GENERALLY LESS THAN 10 MPH.
.FRIDAY...MOSTLY CLOUDY WITH CHANCE OF RAIN AND SNOW. LOWS IN THE
MID TO UPPER 20S. HIGHS IN THE LOWER 40S. WINDS GENERALLY LESS THAN
10 MPH.
.SATURDAY...PARTLY CLOUDY WITH SLIGHT CHANCE OF SHOWERS AND SNOW
SHOWERS. LOWS IN THE MID 20S. HIGHS IN THE UPPER 40S. WINDS
GENERALLY LESS THAN 10 MPH.

$$

FORECASTER...JONES
REQUESTED BY...FLOWERS
REASON FOR REQUEST...PRESCRIBED
.TAG 20100420.HAYFI.01/RIW