Land Management Forecasts
Issued by NWS San Francisco Bay Area, CA
Issued by NWS San Francisco Bay Area, CA
443 FNUS86 KMTR 312156 FWLMTR ECCDA Discussions National Weather Service SAN FRANCISCO BAY AREA 256 PM PDT Sun Aug 31 2025 ##################################################################### ## ## ## Discussions from the latest FWF below ## ## ## ##################################################################### ...Discussion from SFOFWFMTR... We remain on the western periphery of a strong high pressure system. Large scale sinking air, compressional warming and drying aloft, a strong low level temperature inversion coupled with diurnal late August solar warming will continue to produce hot and dry conditions over the interior this afternoon and Labor Day. Conditions remain cooler along the immediate coast due to a shallow marine layer and generally light to locally moderate afternoon sea breezes. Above the shallow marine layer very low daytime humidities and poor overnight recoveries have persisted just away from the immediate coast. Winds remain onshore, but breezy afternoon winds will elevate the fire weather threat in the interior mountains, especially through favored gaps and passes. We are closely monitoring an upper low 500 miles southwest of San Francisco that is forecast to move northeastward and pass across the district later Monday and Tuesday. Chances are low at the moment, but if the pattern evolves with improved timing of the mid-level moisture and best lift associated with the upper level low we could see isolated convection across portions of the Bay Area, East Bay Hills and North Bay. Otherwise there`ll be a deepening of the marine layer with late night and morning spotty light coastal drizzle possible mid week. ...Discussion from SFOFWFEKA... Dry weather will continue through Monday with low daytime RH values in the teens and poor to moderate humidity recoveries in areas well away from the coast. Winds will generally be diurnally and terrain driven. Today a period of enhanced afternoon winds with gusts to 25 mph is expected through this evening. Early through mid week, warming and drying trend is expected with high temperatures forecasted to peak in the upper 90s to near 105 across the interior valleys on Tuesday. There is also a slight chance of afternoon and evening thunderstorms on Tuesday, mainly in Trinity county. In addition, gusty winds combined with hot temperatures and low relative humidity will produce critical fire weather conditions. Existing fires and any new fire will have the potential to spread rapidly. ##################################################################### ## ## ## Complete a discussion for each ECCDA segment below ## ## When done click transmit, product sent as KMTRFWLMTR ## ## ## ##################################################################### ECC010-011000- St Helena ECC Dispatch- DISCUSSION FOR Marin and Sonoma and Napa Counties 256 PM PDT Sun Aug 31 2025 We remain on the western periphery of a strong high pressure system. Large scale sinking air, compressional warming and drying aloft, a strong low level temperature inversion coupled with diurnal late August solar warming will continue to produce hot and dry conditions over the interior this afternoon and Labor Day. Conditions remain cooler along the immediate coast due to a shallow marine layer and generally light to locally moderate afternoon sea breezes. Above the shallow marine layer very low daytime humidities and poor overnight recoveries have persisted just away from the immediate coast. Winds remain onshore, but breezy afternoon winds will elevate the fire weather threat in the interior mountains, especially through favored gaps and passes. We are closely monitoring an upper low 500 miles southwest of San Francisco that is forecast to move northeastward and pass across the district later Monday and Tuesday. Chances are low at the moment, but if the pattern evolves with improved timing of the mid-level moisture and best lift associated with the upper level low we could see isolated convection across portions of the Bay Area, East Bay Hills and North Bay. Otherwise there`ll be a deepening of the marine layer with late night and morning spotty light coastal drizzle possible mid week. $$ ECC014-011000- Morgan Hill ECC Dispatch- DISCUSSION FOR Alameda and Contra Costa and Santa Clara Counties 256 PM PDT Sun Aug 31 2025 We remain on the western periphery of a strong high pressure system. Large scale sinking air, compressional warming and drying aloft, a strong low level temperature inversion coupled with diurnal late August solar warming will continue to produce hot and dry conditions over the interior this afternoon and Labor Day. Conditions remain cooler along the immediate coast due to a shallow marine layer and generally light to locally moderate afternoon sea breezes. Above the shallow marine layer very low daytime humidities and poor overnight recoveries have persisted just away from the immediate coast. Winds remain onshore, but breezy afternoon winds will elevate the fire weather threat in the interior mountains, especially through favored gaps and passes. We are closely monitoring an upper low 500 miles southwest of San Francisco that is forecast to move northeastward and pass across the district later Monday and Tuesday. Chances are low at the moment, but if the pattern evolves with improved timing of the mid-level moisture and best lift associated with the upper level low we could see isolated convection across portions of the Bay Area, East Bay Hills and North Bay. Otherwise there`ll be a deepening of the marine layer with late night and morning spotty light coastal drizzle possible mid week. $$ ECC013-011000- Felton ECC Dispatch- DISCUSSION FOR Santa Cruz and San Mateo Counties 256 PM PDT Sun Aug 31 2025 We remain on the western periphery of a strong high pressure system. Large scale sinking air, compressional warming and drying aloft, a strong low level temperature inversion coupled with diurnal late August solar warming will continue to produce hot and dry conditions over the interior this afternoon and Labor Day. Conditions remain cooler along the immediate coast due to a shallow marine layer and generally light to locally moderate afternoon sea breezes. Above the shallow marine layer very low daytime humidities and poor overnight recoveries have persisted just away from the immediate coast. Winds remain onshore, but breezy afternoon winds will elevate the fire weather threat in the interior mountains, especially through favored gaps and passes. We are closely monitoring an upper low 500 miles southwest of San Francisco that is forecast to move northeastward and pass across the district later Monday and Tuesday. Chances are low at the moment, but if the pattern evolves with improved timing of the mid-level moisture and best lift associated with the upper level low we could see isolated convection across portions of the Bay Area, East Bay Hills and North Bay. Otherwise there`ll be a deepening of the marine layer with late night and morning spotty light coastal drizzle possible mid week. $$ ECC018-011000- Monterey ECC Dispatch- DISCUSSION FOR Monterey and San Benito County 256 PM PDT Sun Aug 31 2025 We remain on the western periphery of a strong high pressure system. Large scale sinking air, compressional warming and drying aloft, a strong low level temperature inversion coupled with diurnal late August solar warming will continue to produce hot and dry conditions over the interior this afternoon and Labor Day. Conditions remain cooler along the immediate coast due to a shallow marine layer and generally light to locally moderate afternoon sea breezes. Above the shallow marine layer very low daytime humidities and poor overnight recoveries have persisted just away from the immediate coast. Winds remain onshore, but breezy afternoon winds will elevate the fire weather threat in the interior mountains, especially through favored gaps and passes. We are closely monitoring an upper low 500 miles southwest of San Francisco that is forecast to move northeastward and pass across the district later Monday and Tuesday. Chances are low at the moment, but if the pattern evolves with improved timing of the mid-level moisture and best lift associated with the upper level low we could see isolated convection across portions of the Bay Area, East Bay Hills and North Bay. Otherwise there`ll be a deepening of the marine layer with late night and morning spotty light coastal drizzle possible mid week. $$