691
FNUS76 KMTR 202351
FWSMTR

Spot Forecast for Site 300 Prescribed Burn 6/21/24...Alameda County Fire
National Weather Service San Francisco CA
451 PM PDT Thu Jun 20 2024

Forecast is based on ignition time of 0800 PDT on June 21.
If conditions become unrepresentative, contact the National Weather
Service.

.DISCUSSION...Friday AM humidity recovery will be poor with RH
around daybreak between 25 and 30 percent. West to northwest
winds gusting to near 25 mph, temperatures in the low to mid 90s
and afternoon humidity falling into the mid to upper teens will
support at least moderate rates of spread---particularly if wind
gusts exceed 25 mph. Transport winds under 10 mph with mixing
heights around 3300 feet AGL will translate to poor to low-end
fair smoke dispersal, with some transport of smoke to the east. RH
recovery will remain poor Friday night into Saturday morning with
winds shifting to the southwest. Hotter and drier conditions are
forecast on Saturday with temperatures just under 100 degrees and
afternoon RH falling down to near 15%. Current wind gusts on Saturday
are around 20 mph, but we`ll monitor the potential to adjust them
upward in future forecast if needed. Ventilation will show a
modest improvement with fair to good smoke dispersal on Saturday.

.FRIDAY...

Sky/weather.........Sunny.
Max temperature.....90-94.
Min humidity........18-22 percent.
Wind (20 ft)........West to northwest winds 5 to 15 mph. Gusts up to 25 mph
                    in the afternoon.
CWR.................0 percent.
LAL.................1.
Mixing height.......3300 ft AGL.
Transport winds.....West around 9 mph.
Marine layer........None.

.FRIDAY NIGHT...

Sky/weather.........Clear.
Min temperature.....68-72.
Max humidity........33-37 percent.
Wind (20 ft)........Southwest winds 7 to 13 mph. Gusts up to 22 mph
                    in the evening.
CWR.................0 percent.
LAL.................1.
Mixing height.......<100 ft AGL.
Transport winds.....West around 12 mph.
Marine layer........None.

.SATURDAY...

Sky/weather.........Sunny.
Max temperature.....95-99.
Min humidity........15-19 percent.
Wind (20 ft)........Northwest winds 5 to 10 mph. Gusts up to 20 mph
                    in the afternoon.
CWR.................0 percent.
LAL.................1.
Mixing height.......6800 ft AGL.
Transport winds.....West around 7 mph.
Marine layer........None.

$$
Forecaster...L_BAIN
Requested by...Brian Diregolo
Type of request...PRESCRIBED
.TAG 2416465.0/MTR
.DELDT 06/20/24
.FormatterVersion 2.0.0
.EMAIL brian.diregolo@acgov.org