FNUS75 KBYZ 252039
FWSBYZ

SPOT FORECAST FOR DRY FORK RX...USFS
NATIONAL WEATHER SERVICE BILLINGS MT
239 PM MDT FRI SEP 25 2009

FORECAST IS BASED ON IGNITION TIME OF 1435 MDT ON SEPTEMBER 25.
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

...RED FLAG WARNING IN EFFECT FROM NOON MDT SATURDAY THROUGH MIDNIGHT
MDT SATURDAY NIGHT FOR HOT AND DRY CONDITIONS ALONG WITH GUSTY
WESTERLY WINDS...

.DISCUSSION...
HIGH PRESSURE WITH VERY WARM AND DRY CONDITIONS WILL PERSIST OVER
THE BURN SITE INTO SATURDAY. MINIMUM RELATIVE HUMIDITIES WILL BOTTOM
OUT IN THE LOWER TO MID 20S TODAY...AND 20 TO 25 PERCENT SATURDAY.
EXPECT NORTHWEST WINDS 5 TO 15 MPH FOR THE REST OF TODAY AND WEST WINDS
5 TO 10 MPH TONIGHT. IT WILL BECOME VERY WINDY ON SATURDAY AHEAD OF
A COLD FRONT APPROACHING FROM THE NORTH. WINDS WILL INCREASE FROM THE
WEST TO 15 TO 25 MPH WITH GUSTS TO 35 MPH. THE COMBINATION OF THE
HOT AND DRY CONDITIONS ALONG WITH GUSTY WINDS SATURDAY INTO SATURDAY
EVENING HAS PROMPTED THE ISSUANCE OF A RED FLAG WARNING FOR THE
BURN SITE.

.REST OF TODAY...

MAX TEMPERATURE.....67-72.
MIN HUMIDITY........21-26 PERCENT.
WIND (20 FT)........
 SLOPE/VALLEY.......NORTHWEST WINDS 5 TO 15 MPH.
 RIDGETOP...........NORTH 10 TO 20 MPH.
MIXING HEIGHT.......6700 FT AGL.
MIXING WINDS........NORTHWEST 5 TO 15 MPH.

.TONIGHT...

MIN TEMPERATURE.....50-55.
MAX HUMIDITY........29-34 PERCENT.
WIND (20 FT)........
 SLOPE/VALLEY.......WEST WINDS 5 TO 10 MPH.
 RIDGETOP...........WEST 10 TO 20 MPH.
MIXING HEIGHT.......1000 FT AGL.
MIXING WINDS........WEST 10 TO 20 MPH.

.SATURDAY...

MAX TEMPERATURE.....68-73.
MIN HUMIDITY........20-25 PERCENT.
WIND (20 FT)........
 SLOPE/VALLEY.......WEST WINDS 15 TO 25 MPH WITH GUSTS TO 35 MPH.
 RIDGETOP...........WEST 25 TO 40 MPH.
MIXING HEIGHT.......6400 FT AGL.
MIXING WINDS........WEST 20 TO 35 MPH.

$$
FORECASTER...ARTHUR
REQUESTED BY...ASHLEY SITES
TYPE OF REQUEST...PRESCRIBED
.TAG 20090925.DRYFO.01/BYZ