FXUS66 KMTR 302007
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
107 PM PDT Mon Mar 30 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 1249 PM PDT Mon Mar 30 2026
- Pattern change today will bring cooler conditions and light
rain Tuesday through Thursday
- Above normal temperatures and offshore flow return Friday and
continue into the weekend
&&
.SHORT TERM...
Issued at 1249 PM PDT Mon Mar 30 2026
(This evening through Tuesday)
The much anticipated pattern change is underway as seen with mid-to-
high level clouds streaming in from a surface low pressure system in
the Eastern Pacific Ocean. Cloudy and relatively cooler conditions,
albeit still above average, can be the sensible weather expected
today. The moisture fetch from the aforementioned low is coming from
the tropics and will arrive tomorrow. While this may sound juicy, it
will still have a dry atmosphere to overcome with little help from
weak forcing. As such, light rain showers will produce little
accumulation with the Big Sur Coast and Santa Cruz Mountains
receiving relatively higher totals with the help of orographic
lift.
&&
.LONG TERM...
Issued at 1249 PM PDT Mon Mar 30 2026
(Tuesday night through next Sunday)
The best chance for rain is Wednesday as a gale force low pressure
system in the Gulf of Alaska heads to the Washington/Canada border.
This system will have better support from surface to jet stream and
will give us a true frontal passage. Beneficial, light rainfall is
expected Wednesday into early Thursday morning. Slick roadways will
be possible coming off a four week dry streak, especially in the
North Bay given that the trajectory of this system being northwest
to southeast. When all is said and done, rainfall totals from
Tuesday to Thursday are expected to amount up to 0.25" with up to
0.50" possible in the higher terrain of the North Bay. The Interior
Central Coast, Interior East Bay Valleys, and Santa Clara Valley
will see a few hundredths at most. Moderate southwesterly winds
ahead of the cold front will increase and back to become
northwesterly in the post-frontal environment. Gusts of 20-30 mph
can be expected with gusts up to 40 mph in the higher terrain. Upper-
level shortwave ridging nosing in from the Eastern Pacific Ocean
will tighten the pressure gradient and result in northerly (drying)
winds on Thursday. As the ridge moves inland Friday, winds will
further increase and veer to become offshore. Impactful winds are
not expected except in the highest terrain. Upper-level longwave
ridging will move in over the weekend, sending temperatures back up
to well above normal.
&&
.AVIATION...
(18Z TAFS)
Issued at 1035 AM PDT Mon Mar 30 2026
VFR conditions expected through the TAF period under a gradually
lowering deck of high clouds. Winds will be gentle to moderate and
diurnally driven. There is a slight but decreasing chance for
stratus Tuesday morning. Disturbed weather is expected Tue-Thu
with persistent mid level clouds, periods of gusty winds and
occasional light rain.
Vicinity of SFO...The airport has been reporting calm winds for
the last several hours. By 20Z onshore winds are expected to
become established in the typical 280-300 direction. Winds will
gradually increase to around 12-15 knots through the afternoon.
Wind speeds will ease back to a gentle breeze through the evening
and overnight hours. There is high confidence in VFR conditions
persisting through the TAF period under lowering high clouds.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...The brief fog impact has cleared and the
terminals will enjoy VFR conditions through the day. There is a
slight chance for stratus to move in around sunrise Tuesday,
particularly at MRY. Otherwise high clouds will persist through
the TAF period ahead of some disturbed weather Tuesday.
&&
.MARINE...
(Today through Saturday)
Issued at 1035 AM PDT Mon Mar 30 2026
Moderate northerly breezes will prevail today, backing to become
southwesterly tomorrow. Fresh westerly breezes on Wednesday will
increase and veer Thursday into Friday to become strong and
northerly. Moderate seas will build to become rough to very rough
Thursday into Friday. Widespread hazardous conditions will return
Thursday as a result. Light rain showers are expected Tuesday
morning through Thursday morning.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&
$$
SHORT TERM...Sarment
LONG TERM....Sarment
AVIATION...Flynn
MARINE...Sarment
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Prepared by Boulder-Creek.com Weather at: Mon Mar 30 16:30:03 PDT 2026
From the National Weather Service
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