FNUS76 KMTR 271540

FWSMTR



Spot Forecast for Ralston Rx...CAL FIRE

National Weather Service San Francisco CA

840 AM PDT Mon Oct 27 2025



Forecast is based on ignition time of 0900 PDT on October 29. 

If conditions become unrepresentative, contact the National Weather

Service.



.DISCUSSION...Warm and dry conditions persist at the burn site

on Wednesday as gentle northeast winds continue through the

morning, turning northwest in the afternoon. Relative humidities

will drop from the 70s in the morning to near 50% during the day.

Overnight, large-scale onshore flow should strengthen the marine 

layer and lead to better humidity recoveries overnight and higher 

humidity retention on Thursday. An inversion should persist 

through the forecast period, limiting vertical smoke dispersion 

at the project site.



.WEDNESDAY...



Sky/weather.........Sunny. 

Max temperature.....74-78. 

Min humidity........46-50 percent. 

Wind (20 ft)........Northeast winds 6 to 9 mph in the morning, becoming 

                    northwest 9 to 12 mph during the afternoon. 

Mixing height.......1300 ft AGL. 

Transport winds.....North around 9 mph. 

Marine layer........1000 ft. 



.WEDNESDAY NIGHT...



Sky/weather.........Mostly clear. 

Min temperature.....51-55. 

Max humidity........92-96 percent. 

Wind (20 ft)........Northwest winds 6 to 10 mph. 

Mixing height.......400 ft AGL. 

Transport winds.....Northwest around 9 mph. 

Marine layer........1000 ft. 



.THURSDAY...



Sky/weather.........Partly sunny. 

Max temperature.....66-70. 

Min humidity........69-73 percent. 

Wind (20 ft)........Northwest winds 7 to 15 mph. 

Mixing height.......1500 ft AGL. 

Transport winds.....Northwest around 9 mph. 

Marine layer........1000 ft. 



$$

Forecaster...D_HOANG

Requested by...Sarah Collamer

Type of request...PRESCRIBED

.TAG 2524548.0/MTR

.DELDT 10/27/25

.FormatterVersion 2.0.0

.EMAIL sarah.collamer@fire.ca.gov