SHORT TERM
Issued at 112 PM PDT Sat Sep 7 2024 (This evening through Sunday)

A ripple through the longwave pattern over the West Coast this afternoon thanks to an upper low sweep eastward through N CA/S OR.
While this feature is bringing showers and thunderstorms up north it's resulted in sunny, but cooler conditions across the Bay Area and Central Coast. Afternoon visible satellite shows marine layer stratus hugging the coast, but inland sunshine. Latest 24 hour trends shows many locations running similar to or colder than 24 hours ago. Despite the "cooldown" there are still many locations well above 90 degrees. One notable place is the Big Sur RAWS sitting at 98 degrees. Pretty impressive given the proximity to the coast. Definitely has a shot at eclipsing 100 degrees. Other far interior locations away from the coast range from 95-105 degrees. These locations have a moderate HeatRisk, but coverage isn't widespread enough to warrant another Heat Advisory.

Fire Weather concerns continues this afternoon as well. Area of greatest concern are the interior N Bay Mts. Last night featured no humidity recovery with places lingering in the single digits for RH. The same is true this afternoon with places holding steady below 10%. Winds are breezy with gusts up to 15 mph. Bone dry conditions with some wind will result in elevated fire weather conditions.

Tonight and Sunday: Marine layer along the coast will gradually move in. Similar to this morning, fog will once again be possible.
Only subtle changes in the overall sensible weather on Sunday.
Coastal clouds with inland sunshine - repeat from Saturday.
Pockets of 100+ deg possible over interior Monterey/San Benito.

LONG TERM
Issued at 130 PM PDT Sat Sep 7 2024 (Sunday night through next Friday)

Additional, but weaker, ripples roll through the upper level pattern through early next week. The lower 500mb heights and cooling airmass will allow for additional cooling both day and night. Onshore flow will persist, which will lead to a deepening of the marine layer and increasing night/morning low clouds. Have added coastal drizzle to the forecast (late night/early morning)
through this timeframe as well.

A more pronounced upper level trough develops by Tuesday night/Wednesday over the PacNW. Given all of the wildfire over OR a lot of hope was riding on this system being wetter, but sadly recent trends are drier. As for our area, some drizzle is possible, but looking more inside slider-ish for Wednesday/Thursday. Temperatures remain cooler on Wednesday/Thursday, but more importantly winds begin to shift with an offshore component. At this point it doens't appear to be a big offshore setup, but something we'll be watching nonetheless.



AVIATION
(18Z TAFS)
Issued at 1022 AM PDT Sat Sep 7 2024

Expect widespread VFR into the afternoon with moderate to breezy winds. VFR and these winds last into the evening before winds reduce and MVFR to LIFR CIGS move inland around the Monterey Bay and SF Bay.
CIGs will build further inland in the late night and some will be accompanied by reduced visibilities from mist and pockets of fog.
Expect mostly light winds overnight and through the late morning on Sunday. CIGS look to erode in the late morning and early afternoon, with moderate to breezy winds that afternoon.

Vicinity of SFO...VFR lasts into the night. Breezy winds build this afternoon but reduce and become moderate in the night as MVFR/IFR CIGs fill around the SF Bay. CIGS erode in the late morning on Sunday with breezy winds returning in the mid-afternoon.

SFO Bridge Approach...Similar to SFO

Monterey Bay Terminals...VFR lasts into the early night before IFR/LIFR CIGs move inland. Expect moderate to breezy winds through the evening before winds reduce. Pockets of mist and fog look to affect the terminals through the late night and through Sunday morning.

MARINE
(Today through Thursday)
Issued at 920 AM PDT Sat Sep 7 2024

Pockets of fog will lift into the afternoon. Expect moderate to breezy north to northwest winds continue through the weekend with occasional gusty winds over the southern waters. Northwest winds strengthen and wave heights increase over the California coastal waters ahead of an incoming low pressure system by the middle of next week with unsettled conditions persisting through the end of the week.

MTR WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...None.