482 
FNUS76 KPDT 300439
FWSPDT

Spot Forecast for POTATO HILL FIRE...YAKAMA AGENCY
National Weather Service Pendleton OR
939 PM PDT Tue Jul 29 2025

Forecast is based on forecast start time of 0600 PDT on July 30. 
***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.

...RED FLAG WARNING IN EFFECT FROM 1 PM TO 9 PM WEDNESDAY FOR 
ABUNDANT LIGHTNING FOR FIRE WEATHER ZONE WA694...

.DISCUSSION...The region remains locked under a weather pattern
favorable for afternoon showers and thunderstorms. A Red Flag
Warning is in effect for Wednesday for the Washington Cascades as
a result. More widespread shower and thunderstorm coverage is 
then expected beginning overnight headed into Thursday morning.
Winds are expected to be light, expect for in the vicinity of
thunderstorms, where outflow winds could gust over 40 mph at
times. 

.WEDNESDAY...

Sky/weather.........Mostly sunny (30-40 percent). Slight chance of 
                    showers and thunderstorms late in the morning
                    (15-25 percent).  
CWR.................0 percent. 
Chance of lightning.18 percent. 
Max temperature.....80-83. 
Min humidity........24-29 percent. 
Wind (20 ft)........Southwest winds 5 to 8 mph shifting to the
                    North-Northwest by the afternoon. 
                    Gusty and erratic winds expected near 
                    thunderstorms. 
Ridgetop wind.......Southeast winds 5 to 10 mph early, shifting to
                    the Northwest by the afternoon.  
Mixing height.......7600 ft AGL. 
Transport winds.....East-Southeast winds 5 to 10 mph early, shifting 
                    to the Northwest by the afternoon. 
Ventilation Index...Poor (50) decreasing to poor (40) in the 
                    afternoon. 

TIME (PDT)      6 AM   8 AM   10 AM  NOON   2 PM   4 PM   
Chc of ltng (%).0      0      0      20     20     20     
Temp............57     65     76     79     79     78     
RH..............48     44     31     30     34     37     
20 ft wind......SW 6   SW 5   W 5    NW 5   NW 6   NW 6    
20 ft wind gust.7      6      6      6      8      8      

.WEDNESDAY NIGHT...

Sky/weather.........Partly cloudy (35-45 percent). Slight chance of 
                    showers and thunderstorms in the evening and 
                    overnight (15-25 percent). 
CWR.................0 percent increasing to 12 percent early in the 
                    morning. 
Chance of lightning.28 percent. 
Min temperature.....54-57. 
Max humidity........59-64 percent. 
Wind (20 ft)........Northwest winds 5 to 8 mph, shifting to the 
                    Southwest overnight. Gusty and erratic 
                    winds expected near thunderstorms.
Ridgetop wind.......Northwest winds 6 to 12 mph, decreasing to around
                    8 mph overnight. 
Mixing height.......600 ft AGL. 
Transport winds.....West-Northwest 6 to 10 mph. 
Ventilation Index...Poor (130) decreasing to poor (30) overnight. 

.THURSDAY...

Sky/weather.........Partly cloudy (50-60 percent). Chance of showers 
                    and thunderstorms (30-40 percent). 
CWR.................12 percent increasing to 39 percent late in the 
                    morning, then decreasing to 17 percent late in 
                    the afternoon. 
Chance of lightning.28 percent. 
Max temperature.....72-75. 
Min humidity........46-51 percent. 
Wind (20 ft)........Southwest winds 5 to 8 mph early, becoming 
                    Northwest 5 to 10 mph by the afternoon. 
                    Gusty and erratic winds expected near 
                    thunderstorms. 
Ridgetop wind.......Northwest winds 6 to 12 mph.  
Mixing height.......3300 ft AGL. 
Transport winds.....West-Northwest 8 to 14 mph. 
Ventilation Index...Poor (60) increasing to fair (210) in the 
                    afternoon. 

$$
Forecaster...Evans
Requested by...SAMANTHA WATLAMET
Type of request...WILDFIRE
.TAG 2518852.0/PDT
.DELDT 07/30/25
.FormatterVersion 2.0.0
.EMAIL samantha_watlamet@yakama.com