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

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633 FXUS66 KMTR 051755 AFDMTR Area Forecast Discussion National Weather Service San Francisco CA 1055 AM PDT Sun May 5 2024 ...New AVIATION, MARINE... .SYNOPSIS... Issued at 104 AM PDT Sun May 5 2024 Isolated post frontal showers will continue through Sunday morning with decreasing intensity. While the next couple days will be chilly, a gradual warming trend will bring temperatures above normal by the end of the week. && .SHORT TERM... (Today and tonight) Issued at 104 AM PDT Sun May 5 2024 The cold front has been quite progressive over the last 24 hours and is now near the CA/Mexico border. The cold air left behind has brought the 1000-500 mb thickness into the mid 530 dm range. This will cause surface temperatures to drop into the low 40s for most areas away from the immediate coast or bay shore. This cold air is also causing some instability, with the low level lapse rates around the conditionally unstable threshold of 6.5 C/km. As such, isolated showers are expected to continue through the morning. The cold air is also drier, and by mid-day there will not be enough moisture to support convection. && .LONG TERM... (Monday through Saturday) Issued at 104 AM PDT Sun May 5 2024 A significant warming trend is in store this week as an upper level ridge forms over the Eastern Pacific. As an example, the high temperature at Santa Rosa on reached 58F on Saturday and is expected to reach 84F by Thursday. A marine layer will likely develop under the high pressure and keep coastal areas cool, although the low-level moisture doesn`t seem to support significant fog or stratus coverage. Overall, it will be a nice week with increasing temperatures and plenty of sunshine. && .AVIATION...
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(18Z TAFS) Issued at 1055 AM PDT Sun May 5 2024 VFR through the TAF period. Gusty west to northwest winds return this afternoon and continue into the evening with light to moderate winds expected overnight. Satellite shows cumulus clouds developing in the South Bay and along the Central Coast. MVFR CIGs are tempoed for SNS and SJC until 19-20Z with moderate to high confidence that as CIGs continue to rise VFR conditions will prevail for the rest of the TAF period. Vicinity of SFO...VFR through the TAF period. Gusty west to northwest winds with gusts up to 25 knots continue through the late evening with guidance indicating gusts drop off between 04-6Z. Moderate to confidence that gusts will not exceed 25 knots with probabilistic guidance indicating a low probability (0-10% chance) of gusts greater than 25 knots. SFO Bridge Approach...Similar to SFO. Monterey Bay Terminals...VFR through the TAF period. Gusty west to northwest winds with gusts up to 20 knots possible through the late evening. Satellite shows cumulus clouds developing over MRY and SNS. Tempoed MVFR conditions from 18-20Z at SNS due to increasing thickness of cloud coverage but 5 minute observations show rising CIG heights which increases confidence that VFR conditions will return by 20Z.
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&& .MARINE...
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(Today through Friday) Issued at 1055 AM PDT Sun May 5 2024 Isolated rain showers linger over the coastal waters with shower potential diminishing heading into the late morning. Dry conditions return by Sunday afternoon and prevail through the forecast period. Moderate to fresh winds continue in portions the southern waters with a coastal jet developing from Point Pinos to Point Piedras Blancas. Elsewhere, moderate northwesterly breezes prevail through tomorrow. Winds strengthen and become more northerly Tuesday through Thursday as surface higher pressure builds and moves eastward. Significant wave heights will begin building on Monday, posing hazardous conditions for small craft through Thursday.
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&& .MTR WATCHES/WARNINGS/ADVISORIES...
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CA...None. PZ...Small Craft Advisory until 3 AM PDT Monday for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm. Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this evening for Pt Arena to Pt Reyes 0-10 nm. Small Craft Advisory until 9 AM PDT Monday for Pt Pinos to Pt Piedras Blancas 0-10 nm.
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&& $$ SHORT TERM...Flynn LONG TERM....Flynn AVIATION...Kennedy 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