Technical NOAA Weather Discussion

FXUS66 KMTR 302340
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
440 PM PDT Mon Mar 30 2026

...New AVIATION...

.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...
(00Z TAFS)
Issued at 415 PM PDT Mon Mar 30 2026

VFR is expected to prevail through the forecast period. Increasing
onshore but relatively light onshore flow will bring some morning
stratus and fog along the coastal sites but struggle to develop
and penetrate farther inland.

Vicinity of SFO...Similar to SFO.

SFO Bridge Approach...VFR is expected to prevail through the
forecast period with relatively light onshore winds overnight,
possibly becoming breezy at times Tuesday afternoon.

Monterey Bay Terminals...VFR is expected to prevail through the
forecast period, however there is a slight chance (less than 20%)
of some low stratus/fog development early Tuesday morning.
Confidence is too low for mention in the TAF. 

&&

.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...JM
MARINE...Sarment

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Prepared by Boulder-Creek.com Weather at: Mon Mar 30 18:30:03 PDT 2026
From the National Weather Service