073
FNUS76 KPDT 152309
FWSPDT

Spot Forecast for Rosenbaum Fire...Oregon Dept of Forestry CIMT3
National Weather Service Pendleton OR
409 PM PDT Sat Aug 15 2026

Forecast is based on forecast start time of 0500 PDT on August 16.
***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...Light winds overnight becoming northerly in the
afternoons through Monday. RHs will be on decline day to day,
with mid 20s tomorrow afternoon and upper teens Monday.
Overnight recovery will be good tonight, but become poor
to fair Sunday night.

.REST OF TONIGHT...

Sky/weather.........Partly cloudy (40-50 percent). Areas of smoke.
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....59-62.
Max humidity........60-65 percent.
Wind (20 ft)........Light winds.
Ridgetop wind.......Light winds.
Mixing height.......400 ft AGL
Transport winds.....Light winds.
Ventilation Index...Low (30).

.SUNDAY...

Sky/weather.........Sunny (10-20 percent). Areas of smoke in the
                    morning, then patchy smoke in the afternoon.
CWR.................0 percent.
Chance of lightning.1 percent.
Max temperature.....85-88.
Min humidity........23-28 percent.
Wind (20 ft)........Light winds becoming west 5 to 8 mph after 1PM,
then shifting to the north 5 to 10 mph
around 5PM.
Ridgetop wind.......Light winds becoming west 5 to 10 mph after
1PM, then shifting to the north 6 to 11 mph
around 5PM.
Mixing height.......8500 ft AGL early in the morning.
Transport winds.....West around 6 mph.
Ventilation Index...Low (30) increasing to moderate (400) in the
                    afternoon.

.SUNDAY NIGHT...

Sky/weather.........Mostly cloudy (65-75 percent).
CWR.................0 percent.
Chance of lightning.1 percent.
Min temperature.....61-64.
Max humidity........41-46 percent.
Wind (20 ft)........North winds 5 to 10 mph becoming drainage winds
after 12AM.
Ridgetop wind.......North winds 6 to 12 mph decreasing 4 to 7 mph
after 11PM.
Mixing height.......500 ft AGL.
Transport winds.....North around 8 mph.
Ventilation Index...Moderate (310) decreasing to low (30)
                    overnight.

.MONDAY...

Sky/weather.........Mostly sunny (40-50 percent).
CWR.................0 percent.
Chance of lightning.5 percent.
Max temperature.....86-89.
Min humidity........19-24 percent.
Wind (20 ft)........Drainage winds becoming northwest 4 to 7 mph
after 12PM.
Ridgetop wind.......North winds 4 to 7 mph shifting to the northwest
5 to 8 mph after 12PM.
Mixing height.......7200 ft AGL early in the morning.
Transport winds.....Northeast around 5 mph.
Ventilation Index...Low (30) increasing to low (70-90) in the
                    afternoon.

$$
Forecaster...Lawhorn
Requested by...Greg Wagenblast
Type of request...WILDFIRE
.TAG 2619762.0/PDT
.DELDT 08/15/26
.FormatterVersion 2.0.0
.EMAIL Greg.Wagenblast@odf.oregon.gov