611
FNUS76 KPDT 121340
FWSPDT
SPOT FORECAST FOR BLACK ROCK - H1...COIMT3
NATIONAL WEATHER SERVICE PENDLETON OR
640 AM PDT FRI SEP 12 2025
FORECAST IS BASED ON FORECAST START TIME OF 0630 PDT ON SEPTEMBER 12.
***THUNDERSTORMS IMPLY GUSTY AND ERRATIC WINDS***
***WINDS ARE 20 FOOT 10-MINUTE AVERAGES***
***CWR-CHANCE OF WETTING RAIN 0.10 OR GREATER***
***VENTILATION INDEX IS DERIVED FROM THE
TRANSPORT WIND MULTIPLIED BY THE MIXING
HEIGHT IN 100'S OF FEET. INDEX CATEGORIES
ARE A GENERALIZED INDICATOR ONLY.***
IF YOU HAVE QUESTIONS OR CONCERNS WITH THIS FORECAST, PLEASE
CONTACT OUR OFFICE AT (541) 276-8134.
DISCUSSION
WARMER, DRIER WEATHER IS FORECAST TODAY THROUGH SATURDAY
AS A BRIEF RIDGE OF HIGH PRESSURE BUILDS OVER THE PACIFIC NORTHWEST.
CHANCES OF SHOWERS AND THUNDERSTORMS ARE VERY LOW (<5%) WITH ANY
ACTIVITY EXPECTED OVER THE BLUE MOUNTAINS. MINIMUM RHS ARE ANTICIPATED TO
FALL SATURDAY AFTERNOON. SHOWER AND THUNDERSTORM CHANCES THEN RETURN
SATURDAY NIGHT AND SUNDAY AS A LOW-PRESSURE SYSTEM IS LIKELY
(>80% CONFIDENCE) TO MOVE ONSHORE.
REST OF TODAY
SKY/WEATHER.........SUNNY (5-15 PERCENT).
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.1 PERCENT.
MAX TEMPERATURE.....78-81.
MIN HUMIDITY........34-39 PERCENT.
WIND (20 FT)........SOUTHWEST WINDS 5 TO 8 MPH SHIFTING TO THE
NORTHWEST LATE IN THE AFTERNOON.
RIDGETOP WIND.......SOUTHWEST WINDS 5 TO 8 MPH SHIFTING TO THE
NORTHWEST LATE IN THE AFTERNOON. GUSTS UP
TO 15 MPH.
MIXING HEIGHT.......INCREASING TO 5000 TO 5500 FT AGL BY AFTERNOON.
TRANSPORT WINDS.....SOUTHWEST 5-8 MPH SHIFTING TO THE
NORTHWEST LATE IN THE AFTERNOON.
VENTILATION INDEX...POOR (70) INCREASING TO POOR (190) IN THE
AFTERNOON.
TIME (PDT) 6 AM 8 AM 10 AM NOON 2 PM 4 PM
CHC OF LTNG (%).0 0 0 0 0 0
TEMP............54 56 63 70 75 78
RH..............84 82 73 58 47 41
20 FT WIND......S 7 S 8 S 8 SW 7 NW 7 NW 7
20 FT WIND GUST. 10 10 10 10 10
TONIGHT
SKY/WEATHER.........MOSTLY CLEAR (10-20 PERCENT).
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.1 PERCENT.
MIN TEMPERATURE.....AROUND 60.
MAX HUMIDITY........64-69 PERCENT.
WIND (20 FT)........NORTHWEST WINDS 5 TO 7 MPH EARLY IN THE EVENING
SHIFTING TO THE SOUTH 5 TO 8 MPH OVERNIGHT.
RIDGETOP WIND.......NORTHWEST WINDS 5 TO 9 MPH SHIFTING TO THE
SOUTH OVERNIGHT. GUSTS UP TO 15 MPH.
MIXING HEIGHT.......800 FT AGL.
TRANSPORT WINDS.....NORTH 5 TO 6 MPH SHIFTING TO THE SOUTHWEST
AROUND 6 MPH OVERNIGHT.
VENTILATION INDEX...POOR (100) DECREASING TO POOR (30) OVERNIGHT.
SATURDAY
SKY/WEATHER.........SUNNY (5-15 PERCENT).
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.1 PERCENT.
MAX TEMPERATURE.....83-86.
MIN HUMIDITY........26-31 PERCENT.
WIND (20 FT)........SOUTH WINDS 5 TO 8 MPH SHIFTING TO THE WEST
TO NORTHWEST LATE IN THE AFTERNOON.
RIDGETOP WIND.......SOUTH WINDS 5 TO 9 MPH SHIFTING TO THE WEST
TO NORTHWEST LATE IN THE AFTERNOON.
MIXING HEIGHT.......6000 FT AGL.
TRANSPORT WINDS.....SOUTH AROUND 6 MPH SHIFTING TO THE WEST AROUND
7 MPH LATE IN THE AFTERNOON.
VENTILATION INDEX...POOR (50) INCREASING TO FAIR (200) IN THE
AFTERNOON.
FORECASTER...LAWHORN/PLUNKETT
REQUESTED BY...KATHY REED
TYPE OF REQUEST...WILDFIRE
.TAG 2521661.2/PDT
.DELDT 09/12/25
.FORMATTERVERSION 2.0.0
.EMAIL KATHERINE.REED@USDA.GOV
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page