650
FNUS76 KPDT 242211
FWSPDT

Spot Forecast for Balloon Tree...USFS
National Weather Service Pendleton OR
311 PM PDT Mon Aug 24 2026

Forecast is based on forecast start time of 1800 PDT on August 24.
***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.

****No Forecast Update to Tonight and Tuesday sections since earlier
forecast request****

.DISCUSSION...Light terrain driven winds will prevail through
tonight, becoming southerly tomorrow morning and afternoon.
Northwest winds will develop in the early evening, becoming light
overnight. Afternoon RHs are expected to dip into the teens later
tomorrow afternoon, with poor overnight recovery tonight and
tomorrow night. Unstable conditions will develop Tuesday
afternoon, with a slight chance (10-15%) of an isolated thunderstorm
impacting the fire area.

.TONIGHT...

Sky/weather.........Partly cloudy (25-35 percent). Areas of smoke
                    in the evening.
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....59-62.
Max humidity........36-41 percent.
Wind (20 ft)........Upslope winds becoming north 5 to 7 around 6PM,
then shifting to the northwest around 9PM, then
becoming downslope winds around 12AM.
Ridgetop wind.......Light variable winds becoming north winds 5 to
10 mph around 6PM, shifting to the northwest
around 9PM, then becoming light variable winds
around 3AM.
Mixing height.......500 ft AGL.
Transport winds.....Northeast 6 to 10 mph shifting to the southeast
                    around 6 mph early in the morning.
Ventilation Index...Low (130) decreasing to low (40) overnight.

TIME (PDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Chc of ltng (%).0   0   0   0   0   0   0   0   0   0   0   0
Temp............83  79  76  73  72  71  70  69  67  66  64  63
RH..............21  26  29  29  29  30  30  32  33  36  37  39
20 FT wind dir..N   N   N   NW  NW  NW  N   N   NW  N   N   N
20 FT wind spd..5   7   6   5   5   5   4   4   3   2   2   2
20 FT wind gust.

.TUESDAY...

Sky/weather.........Mostly sunny (30-40 percent). Patchy smoke late
                    in the afternoon. Slight chance of showers and
                    thunderstorms late in the afternoon.
CWR.................0 percent.
Chance of lightning.15 percent.
Max temperature.....89-92.
Min humidity........16-21 percent.
Wind (20 ft)........Downslope winds becoming southeast 3 to 6 mph
around 9AM, then shifting to the south 5 to
10 mph around 11AM. Gusty and erratic winds
expected near thunderstorms late in the
afternoon.
Ridgetop wind.......Light variable winds becoming southeast 4 to
7 mph shifting to the south 6 to 11 mph
around 11AM. Gusty and erratic winds expected
near thunderstorms late in the afternoon.
Mixing height.......10700 ft AGL in the afternoon.
Transport winds.....South 6 to 14 mph shifting to the west around 5
                    mph late in the afternoon.
Ventilation Index...Low (60) increasing to very high (960) in the
                    afternoon.

.TUESDAY NIGHT...

Sky/weather.........Mostly cloudy (55-65 percent) then becoming
                    partly cloudy (20-30 percent). Slight chance of
                    showers and thunderstorms early in the evening.
                    Patchy smoke.
CWR.................0 percent.
Chance of lightning.15 percent.
Min temperature.....61-64.
Max humidity........39-44 percent.
Wind (20 ft)........Northwest winds 5 to 8 mph, becoming downslope
around 3AM. Gusty and erratic winds expected
                    near thunderstorms early in the evening.
Ridgetop wind.......Northwest winds 6 to 12 mph decreasing to
5 to 8 mph around 3AM. Gusty and erratic winds
expected near thunderstorms early in the evening.
Mixing height.......500 ft AGL in the evening and overnight then
                    500 ft AGL early in the morning.
Transport winds.....West around 5 mph shifting to the northwest 6
                    to 7 mph early in the evening, then shifting to
                    the east around 5 mph early in the morning.
Ventilation Index...Low (110) decreasing to low (30) overnight.

$$
Forecaster...Lawhorn
Requested by...IC Weseman
Type of request...WILDFIRE
.TAG 2620299.5/PDT
.DELDT 08/24/26
.FormatterVersion 2.0.0
.EMAIL orbmc@firenet.gov