FNUS75 KBYZ 201241
FWSBYZ

SPOT FORECAST FOR E-R RX...BLM
NATIONAL WEATHER SERVICE BILLINGS MT
641 AM MDT MON APR 20 2009

FORECAST IS BASED ON IGNITION TIME OF 0700 MDT ON APRIL 20.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

.DISCUSSION...
A RIDGE OF HIGH PRESSURE WILL BE OVER THE BURN SITE TODAY THROUGH
TUESDAY. THIS FEATURE WILL BRING ABOVE NORMAL TEMPERATURES IN THE
MID 70S TO AROUND 80 DEGREES BOTH DAYS. RELATIVE HUMIDITIES WILL BE
LOW BOTH DAYS IN THE MID TEENS TO AROUND 20 PERCENT. A STRONG
NORTHWEST FLOW ALOFT WILL MIX DOWN TO THE SURFACE BOTH DAYS. LIGHT
DOWNSLOPE/DOWN VALLEY WINDS EARLY THIS MORNING WILL BECOME NORTHWEST
AND INCREASE TO 20 TO 30 MPH WITH GUSTS TO AROUND 35 MPH THIS
AFTERNOON. THESE GUSTY WINDS WILL DIMINISH TO LIGHT DOWNSLOPE/DOWN
VALLEY BY LATE THIS EVENING. IT WILL NOT BE QUITE AS WINDY ON TUESDAY.
LIGHT DOWNSLOPE/DOWN VALLEY WINDS EARLY IN THE MORNING WILL INCREASE
BY LATE MORNING TO NORTHWEST 10 TO 20 MPH.

.TODAY...

SKY/WEATHER.........PARTLY CLOUDY.
CWR.................0 PERCENT.
LAL.................1...NO THUNDERSTORMS.
MAX TEMPERATURE.....75-80.
MIN HUMIDITY........14-19 PERCENT.
WIND (20 FT)........
 SLOPE/VALLEY.......DOWNSLOPE/DOWN VALLEY WINDS 5 MPH OR LESS
                    EARLY...BECOMING NORTHWEST 10 TO 20 MPH BY LATE
                    MORNING...INCREASING TO NORTHWEST 20 TO 30 MPH
                    DURING THE AFTERNOON WITH GUSTS TO AROUND 35 MPH.
 RIDGETOP...........NORTHWEST 15 TO 30 MPH.
MIXING HEIGHT.......7800 FT AGL.
MIXING WINDS........NORTHWEST 15 TO 30 MPH.

.TONIGHT...

SKY/WEATHER.........PARTLY CLOUDY.
CWR.................0 PERCENT.
LAL.................1...NO THUNDERSTORMS.
MIN TEMPERATURE.....40-45.
MAX HUMIDITY........65-70 PERCENT.
WIND (20 FT)........
 SLOPE/VALLEY.......NORTHWEST WINDS 20 TO 30 MPH AND GUSTY EARLY...
                    DIMINISHING TO DOWNSLOPE/DOWN VALLEY 5 MPH
                    OR LESS BY LATE EVENING.
 RIDGETOP...........NORTHWEST 15 TO 30 MPH.
MIXING HEIGHT.......300 FT AGL.
MIXING WINDS........NORTHWEST 15 TO 30 MPH.

.TUESDAY...

SKY/WEATHER.........SUNNY.
CWR.................0 PERCENT.
LAL.................1...NO THUNDERSTORMS.
MAX TEMPERATURE.....76-81.
MIN HUMIDITY........15-20 PERCENT.
WIND (20 FT)........
 SLOPE/VALLEY.......DOWNSLOPE/DOWN VALLEY 5 MPH OR LESS EARLY...
                    BECOMING NORTHWEST 10 TO 20 MPH BY LATE MORNING.
 RIDGETOP...........NORTHWEST 10 TO 20 MPH.
MIXING HEIGHT.......7900 FT AGL.
MIXING WINDS........NORTHWEST 15 TO 25 MPH.

$$
FORECASTER...ARTHUR
REQUESTED BY...UNDERWOOD
TYPE OF REQUEST...PRESCRIBED
.TAG 20090420.ERRX_.01/BYZ