776
FNUS76 KPDT 111925
FWSPDT

Spot Forecast for Little Dean 16...USFS
National Weather Service Pendleton OR
1225 PM PDT Mon May 11 2026

Forecast is based on ignition time of 0600 PDT on May 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 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...Hot, dry conditions are expected Tuesday, with a
very low (5 percent) chance of high-based showers and thunderstorms
in the late afternoon and evening hours. Showers are likely
(60 percent chance) Tuesday night and Wednesday, and there is a slight
chance (15 percent) of thunderstorms. Any showers and thunderstorms
that develop Tuesday afternoon through Wednesday will be capable of
producing strong, gusty, and erratic outflow winds.

.TUESDAY...

Sky/weather.........Mostly sunny (10-25 percent).
CWR.................0 percent.
Chance of lightning.1 percent.
Max temperature.....81-84.
Min humidity........12-17 percent.
Wind (20 ft)........Drainage winds early morning, becoming upslope
                    then upvalley winds early to mid-morning, then
                    becoming southeast to south 6-10 mph with gusts
                    of 15-20 mph late morning and afternoon.
Ridgetop wind.......Southeast winds 4-7 mph through mid-morning,
                    becoming southeast to south to 8-12 mph with gusts
                    of 17-22 mph late morning and afternoon.
Mixing height.......Increasing to 8000-8500 ft AGL by late morning.
Transport winds.....Southeast 4-8 mph through mid-morning, shifting
                    to the south 12-17 mph by late morning.
Ventilation Index...Low (60) increasing to very high (980) 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............52     56     66     74     79     81
RH..............42     38     28     23     19     17
20 ft wind......SE 2   SE 2   SE 6   SSE 8  S 9    S 9
20 ft wind gust.              15     18     18     18

.TUESDAY NIGHT...

Sky/weather.........Partly cloudy (25-45 percent) in the evening,
                    becoming mostly cloudy (60-90 percent) overnight.
                    Chance (50 percent) of rain showers, and very low
                    chance (10 percent) of thunder overnight.
CWR.................5 percent.
Chance of lightning.10 percent.
Min temperature.....52-55.
Max humidity........52-57 percent.
Wind (20 ft)........South winds 5-8 mph with gusts of 10-15 mph,
                    becoming southwest to west overnight. Showers and
                    thunderstorms will be capable of producing strong,
                    gusty, and erratic outflow winds up to 60 mph.
Ridgetop wind.......South winds 7-12 mph with gusts of 12-17 mph,
                    becoming southwest to west overnight. Showers and
                    thunderstorms will be capable of producing strong,
                    gusty, and erratic outflow winds up to 60 mph.
Mixing height.......Decreasing to 400-700 ft AGL overnight.
Transport winds.....South 8-12 mph shifting to the southwest
                    6-10 mph overnight.
Ventilation Index...Decreasing to low (30) overnight.

.WEDNESDAY...

Sky/weather.........Mostly cloudy (70-90 percent) Rain showers likely
                    (60 percent chance), and slight chance (15 percent)
                    of thunderstorms.
CWR.................25 percent.
Chance of lightning.15 percent.
Max temperature.....62-65.
Min humidity........35-40 percent.
Wind (20 ft)........Southwest winds 8-12 mph with gusts of 20-30
                    mph in the morning, becoming west to northwest
                    10-15 mph with gusts of 20-30 mph in the afternoon.
                    Showers and thunderstorms will be capable of producing
                    strong, gusty, and erratic outflow winds up to 60 mph.
Ridgetop wind.......Southwest winds 10-15 mph with gusts of 20-30
                    mph in the morning, becoming west to northwest
                    12-17 mph with gusts of 25-35 mph in the afternoon.
                    Showers and thunderstorms will be capable of producing
                    strong, gusty, and erratic outflow winds up to 60 mph.
Mixing height.......Increasing to 5500-6000 ft AGL by late morning.
Transport winds.....Southwest 8-14 mph in the morning, becoming
                    northwest 15-20 mph in the mid-afternoon.
Ventilation Index...Increasing to very high (800) in the afternoon.

$$
Forecaster...Plunkett
Requested by...Kira Santulli
Type of request...PRESCRIBED
.TAG 2613395.0/PDT
.DELDT 05/11/26
.FormatterVersion 2.0.0
.EMAIL lane.mcdonald@usda.gov,kira.santulli@usda.gov,neil.fletcher@usda.gov,brett.johnson@usda.gov