Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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542 FXUS66 KMTR 162345 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 445 PM PDT Sun Jun 16 2024 ...New AVIATION, MARINE... .SYNOPSIS... Issued at 124 PM PDT Sun Jun 16 2024 Red Flag Warning has been issued for the North Bay Interior Mountains from 11 AM to 8 PM Monday. Dry and breezy conditions continue into Monday night. Better onshore flow and moisture return by midweek. Another warming trend on the way for the upcoming weekend. && .SHORT TERM... (This evening through Monday) Issued at 124 PM PDT Sun Jun 16 2024 Visible satellite showing mostly clear skies across the area aside from some high clouds over northern portions of the CWA. This is in response to the trough moving into the western US that is ultimately responsible for our current windy conditions. These conditions are expected to last through Monday night. As such, a Red Flag Warning was issued in effect from 11 AM to 8 PM Monday for interior high elevation portions of the North Bay. This is a marginal case for Red Flag, but the decision was ultimately driven by RH as low as 10% - potentially single digits - and gusty winds to 30 mph as well as limited RH recovery Monday night going into Tuesday morning. These conditions appear to be fairly limited to interior Napa county above about 1,000 feet. Elevated fire weather concerns continue to exist elsewhere, but other locations won`t see RH values as critical as interior Napa and will have better overnight RH recovery. Otherwise, Monday looks like a fairly pleasant day with highs in the 70s to lower 80s. && .LONG TERM... (Tuesday through next Saturday) Issued at 124 PM PDT Sun Jun 16 2024 For the rest of the week, the main upper low moves out into the northern plains while a weak trough pattern remains but slowly degrades. Not much change in sensible weather through midweek as a result. A warming trend kicks off late in the week as 500mb heights continue to rise. Cluster guidance and ensemble guidance generally support this pattern with a broad ridge building across the west. Still looking into the D6-7 range here, but the coming weekend will be something to keep an eye on regarding elevated HeatRisk for inland areas. && .AVIATION...
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(00Z TAFS) Issued at 445 PM PDT Sun Jun 16 2024 Clear skies throughout our region with North Bay terminals experience a bit of haze and smoke from fires in the county. Flight category still remains VFR and is expected to prevail through the TAF period for all terminals. The only aviation concerns will be strong gusty wind this evening. Winds will be predominately westerly/northwesterly and will remain onshore through the TAF period. Winds diminish overnight for most terminals but will remain relatively moderate to breezy for most terminals. Gusty strong winds will return Monday afternoon with chances of gust up to 25-30 knots. Vicinity of SFO...High confidence of VFR through the TAF period. Gusty onshore winds will prevail until early morning where winds will diminish briefly before rebuilding Monday late morning. Currently observation show gusty winds up to 40 knots. Therefore, AWW was issued through 07Z. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR continue to prevail through the TAF period. Westerly to northwesterly winds gusty winds continuing into the evening and will transition to light to moderate winds overnight. Possible few to scattered low clouds may develop overnight but not anticipated to become MVFR.
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&& .MARINE...
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(Tonight through next Friday) Issued at 445 PM PDT Sun Jun 16 2024 Widespread gale force gusts continue before diminishing in areal coverage and intensity late Sunday night. By early Monday, gale force gusts will have weakened to strong to near gale force with widespread conditions dangerous to small crafts persisting through mid-week. Significant wave heights will peak between 12 to 14 feet Sunday into Monday before gradually diminishing to 8 to 11 feet by mid- week. Hazardous conditions will persist through the late work week with strong gusts expected to continue over the majority of the coastal waters.
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&& .FIRE WEATHER... Issued at 124 PM PDT Sun Jun 16 2024 ...Elevated Fire Weather Conditions Through The Weekend... *Breezy to gusty northerly winds, especially higher terrain *Lowering relative humidity values day and night Much of the detail regarding the Red Flag Warning for the interior North Bay mountains is outlined in the SHORT TERM section. Elevated fire weather conditions continue area-wide through Monday. We continue to see small vegetation and grass fires today, showing that fine fuels are very susceptible. Better moisture return enters the picture by midweek, though dry afternoons persist. Behringer && .MTR WATCHES/WARNINGS/ADVISORIES...
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CA...Red Flag Warning from 11 AM to 8 PM PDT Monday for CAZ504. PZ...Small Craft Advisory until 3 AM PDT Monday for Mry Bay-SF Bay N of Bay Bridge. Gale Warning until 3 AM PDT Monday for Pigeon Pt to Pt Pinos 0- 10 nm-Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0- 10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.
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&& $$ SHORT TERM...Behringer LONG TERM....Behringer AVIATION...SO MARINE...Kennedy Visit us at www.weather.gov/sanfrancisco Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea