511
FNUS76 KPDT 231521
FWSPDT

Spot Forecast for Triple Butte Unit 4...Confederated Tribes of Warm Springs
National Weather Service Pendleton OR
821 AM PDT Fri Oct 23 2026

Forecast is based on ignition time of 1000 PDT on October 23.
***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 transport wind
   multiplied by the mixing height in 100`s of ft.
   Categories are a generalized indicator only:
   low (< 200), moderate (200-500), high (500-700),
   and very high (> 700).                           ***

If you have questions or concerns with this forecast, please
contact our office at (541) 276-8134.

.DISCUSSION...Breezy west to northwest winds along ridgetops this
morning will slacken through the day. In sheltered areas of the burn
site, expecting lighter west winds with periodic gusts. For sheltered
areas, terrain-driven winds are forecast to return late this evening,
while west winds will become southeast along ridgetops. Excellent RH
recovery is anticipated late evening into the early overnight, albeit
with RH decreasing to good overnight into early morning.

.REST OF TODAY...

Sky/weather.........Mostly cloudy (55-85 percent) early morning,
                    becoming mostly sunny (5-25 percent) by late
                    morning.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....46-49.
Min humidity........55-60 percent.
Wind (20 ft)........West-northwest winds 4-8 mph with gusts up to 15 mph.
Ridgetop wind.......West to northwest 15-25 mph with gusts up to 30 mph
                    in the morning, decreasing to 8-12 mph with gusts
                    of 12-17 mph by afternoon.
Mixing height.......Increasing to 1800-2200 ft AGL by early afternoon.
Transport winds.....West to west-northwest 10-15 mph, strongest in the
                    morning.
Ventilation Index...Increasing to moderate (210) in the afternoon.

TIME (PDT)      10 AM  NOON   2 PM   4 PM   6 PM   8 PM
Chc of ltng (%).0      0      0      0      0      0
Temp............36     40     43     44     39     33
RH..............75     65     60     61     78     85
20 ft wind......WNW 8  WNW 6  WNW 6  WNW 5  W 4    W 4
20 ft wind gust.14     12     10     8

.TONIGHT...

Sky/weather.........Mostly clear to partly cloudy (15-35 percent).
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....29-32.
Max humidity........85-90 percent.
Wind (20 ft)........Becoming terrain-driven winds 1-4 mph by late
                    evening.
Ridgetop wind.......West 4-8 mph in the evening, becoming southeast
                    3-7 mph around midnight.
Mixing height.......Decreasing to 200-500 ft AGL overnight.
Transport winds.....West 8-12 mph in the evening, becoming south
                    to southeast 3-7 mph around midnight.
Ventilation Index...Decreasing to low (30) overnight.

$$
Forecaster...Plunkett
Requested by...Jeffrey Casey
Type of request...PRESCRIBED
.TAG 2624421.0/PDT
.DELDT 10/23/26
.FormatterVersion 2.0.0
.EMAIL Jeff.Casey@ctwsbnr.org