FXUS66 KMTR 241117
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
415 AM PDT Tue Mar 24 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1137 PM PDT Mon Mar 23 2026
- Slightly above normal temperatures will persist into the
weekend
- Dry weather continues this week; increasing potential for light
rain to return beginning of April
- Moderate offshore winds across the North Bay Interior Mountains
Thursday into Friday
&&
.SHORT TERM...
Issued at 1137 PM PDT Mon Mar 23 2026
(Tonight through Wednesday)
Currently clear skies on satellite with just a few high clouds
drifting across the North Bay and Central Coast. Confidence is low
that stratus will be able to develop overnight given the rebuilding
ridge and compressed marine layer. A look at the current RH values
shows fairly dry conditions across the region which further
decreases confidence that stratus will be able to develop tonight.
High resolution guidance (HREF, HRRR) both support clear skies
continuing through the rest of the night with fog not anticipated to
develop.
Seasonal to slightly above normal temperatures continue on Tuesday
as ridging rebuilds over the Western United States. This will see a
continuation of high temperatures in the 70s to low 80s across the
interior and 60s to 70s along the coastline. Interior Monterey and
San Benito counties remain the warmest locations with high
temperatures in the mid to upper 80s. Minor HeatRisk continues
through the end of the week. This primarily impacts those who are
extremely sensitive to heat with minimal impacts expected for the
population at large. Overnight low temperatures will be in the upper
40s to 50s across the region.
&&
.LONG TERM...
Issued at 1137 PM PDT Mon Mar 23 2026
(Wednesday night through next Monday)
While still above normal, temperatures are expected to cool slightly
(3-6 degrees) Wednesday compared to Tuesday. High temperatures
across the board Wednesday and Thursday will be in the 70s across
the interior, 60s along the coast, and mid 80s across the interior
Central Coast. Why are temperatures cooling? Glad you asked. While
the upper level ridge is currently rebuilding over the West Coast,
it won't stay centered over southern California for very long. A cut-
off low is expected to merge back into the jet stream and move
through California (becoming a weak upper level trough) Wednesday
into Thursday. This trough will displace the center of the ridge and
warmest temperatures eastward. At the same time, a deep upper level
trough and surface low pressure system will make their way into the
Pacific Northwest Tuesday into Wednesday. The trailing cold front
associated with this system will extend southwards into California
and reach the Bay Area Wednesday/Thursday. While the front does fall
apart as it moves through the Bay Area, it will bring a cooler
airmass with it that will help to keep our temperatures cooler. It
is expected to be a dry frontal passage so don't get too hopeful for
rain just yet. At most we may see some drizzle on Wednesday over the
marine environment. More notably, we can expect winds across the
marine environment to strengthen with widespread gale force gusts
across the outer waters Wed-Thurs. Gusty onshore winds (20-35 mph)
will spread along the coastline and across the higher elevations
Wednesday into Thursday as cold frontal passage occurs. Temperatures
remain fairly consistent in the 70s to low 80s across the interior
and 60s to 70s along the coast Friday through the remainder of the
weekend. A potential pattern change remains possible early next week
as a deep upper level trough remains on track to approach the West
Coast. This system will bring us our next chance of light rain.
Moderate offshore (NE) winds look to develop across the North Bay
Interior Mountains Thursday into Friday as high pressure strengthens
across the Intermountain West and thermal troughing develops over
CA. The strongest winds should stay over the higher elevations/along
the ridgeline with gusts between 30 to 40 mph expected. Fire
concerns remain low at this time but smaller fuels (grass) are
curing due to the recent abnormally hot temperatures.
&&
.AVIATION...
(12Z TAFS)
Issued at 415 AM PDT Tue Mar 24 2026
Strong to record breaking strong 500 mb heights and lower to mid
level thermal ridging (for Oakland upper air soundings in late
March since 1948) i.e. subsidence continues to keep conditions
clear /VFR/. Cooler air is undercutting the ridge within a shallow
layer closest to the sea surface and there is nocturnal radiative
cooling in the valleys. It's a near high confidence VFR forecast
for the 12z TAFs, except patchy fog and/or low stratus /LIFR-IFR/
may form along the immediate coastline tonight and Wednesday
morning.
Vicinity of SFO...VFR. Light and variable wind becoming westerly
10 to 20 knots in the afternoon and evening. Light westerly wind
tonight becoming light and variable Wednesday morning.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. East to southeast winds 5 to 15 knots
becoming west 10 to 15 knots in the afternoon. Light southeast winds
developing tonight and Wednesday morning.
&&
.MARINE...
(Today through Sunday)
Issued at 335 AM PDT Tue Mar 24 2026
Moderate to fresh northwesterly breezes and moderate seas will
prevail through today. Strong to near gale northerly winds will
develop Wednesday into Thursday with gale force gusts expected for
the inner waters and outer waters. Rough to very rough seas will
build as a result. Conditions improve by Friday.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM to 9 PM PDT Wednesday for Mry Bay.
Small Craft Advisory from 9 AM to 9 PM PDT Wednesday 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.
Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
evening for Pt Pinos to Pt Piedras Blancas 0-10 nm.
Gale Watch from Wednesday evening through Thursday afternoon for
Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...Kennedy
LONG TERM....Kennedy
AVIATION...Canepa
MARINE...Canepa
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Prepared by Boulder-Creek.com Weather at: Tue Mar 24 04:30:03 PDT 2026
From the National Weather Service
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