567
FNUS76 KMTR 181627
FWSMTR

Spot Forecast for H-Ranch Prescribed Fire...Marin County Fire Department
National Weather Service San Francisco CA
927 AM PDT Sat Oct 18 2025

Forecast is based on ignition time of 1000 PDT on October 18.
If conditions become unrepresentative, contact the National Weather
Service.

.DISCUSSION...Offshore flow will redevelop by late this morning
and continue through this afternoon. By this evening, winds will
shift back onshore (westerly) and remain onshore through the rest
of the forecast period. There is some potential for light offshore
flow to develop early Sunday morning but this is expected to be
temporary with winds predominantly onshore. Gusts are expected to
peak around 15 mph on Saturday with gusts peaking between 15 to
20 mph on Sunday. Probabilistic guidance shows a 40-45% chance of
gusts greater than 15 mph developing Sunday afternoon and evening.
Fair daytime humidity retention between 48-53% is expected
Saturday and Sunday with good overnight humidity recoveries around
75-80%.

.REST OF TODAY...

Sky/weather.........Sunny.
Max temperature.....72-76.
Min humidity........48-52 percent.
Wind (20 ft)........East to Northeast winds 5 to 10 mph
                    with gusts to around 15 mph in the afternoon/evening.
CWR.................0 percent.
Chance of thunder...0 percent.
Mixing height.......1400 ft AGL.
Transport winds.....East around 7 mph.
Marine layer........None.

.TONIGHT...

Sky/weather.........Clear.
Min temperature.....53-57.
Max humidity........77-81 percent.
Wind (20 ft)........West winds 7 to 10 mph with gusts to around 15 mph
                    in the evening.
CWR.................0 percent.
Chance of thunder...0 percent.
Mixing height.......0 ft AGL.
Transport winds.....West around 6 mph.
Marine layer........None.

.SUNDAY...

Sky/weather.........Sunny.
Max temperature.....72-76.
Min humidity........49-53 percent.
Wind (20 ft)........West winds 5 to 15 mph with gusts to around
                    15 to 20 mph in the afternoon/evening.
CWR.................0 percent.
Chance of thunder...0 percent.
Mixing height.......1300 ft AGL.
Transport winds.....West around 8 mph.
Marine layer........None.

$$
Forecaster...R_KENNEDY
Requested by...Graham Groneman
Type of request...PRESCRIBED
.TAG 2523796.1/MTR
.DELDT 10/18/25
.FormatterVersion 2.0.0
.EMAIL graham.groneman@marincounty.gov