Technical NOAA Weather Discussion

FXUS66 KMTR 121136
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
436 AM PDT Sun Apr 12 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 1229 AM PDT Sun Apr 12 2026

 - Scattered light showers with a slight chance of thunderstorms 
   today will linger into early Monday

 - A gradual warming and drying trend returns through the
   remainder of extended forecast
 
 - Gusty winds, especially at higher elevations Wednesday and
   Thursday

&&

.SHORT TERM...
Issued at 1229 AM PDT Sun Apr 12 2026
(Today and tonight)

The center of the upper level low will continue to slowly move 
onshore through the overnight as a secondary trough on the backside 
of the low shifts south well offshore today. Scattered weak showers 
offshore will drift onshore overnight, followed by scattered light 
showers, primarily over the North Bay after sunrise this morning and 
over the coastal ranges. Coverage of light showers will begin to 
increase once again by late morning into the afternoon as an upper 
trough axis shifts east-southeast across our area. There is a slight 
chance of thunderstorms after sunrise especially from areas where 
upslope flow will provide extra lift near the coastal ranges and 
eastern half of our forecast area. Temperatures will be slightly 
cooler than today, mostly from the mid-50s to mid-60s. Shower 
activity should mostly taper off by sunset. Rain totals will be 
light through the day, with up to a 0.25" for low lying areas, and 
up to 0.75" at higher elevations.

&&

.LONG TERM...
Issued at 1229 AM PDT Sun Apr 12 2026
(Monday through Saturday)

Monday morning will feature some lingering offshore showers that may 
drift into Monterey County with only a few hundredths of rain 
expected where it does rain. By Tuesday, low amplitude ridging will 
begin a pleasant gradual warming trend. A sharpening trough axis 
extending southwest from a developing system from the Pacific 
Northwest into the Great Basin will produce a 'back door slider' 
pattern for the second of the week. Gusty west winds at higher 
elevations on Wednesday will become northerly and the strongest 
gusts appear to not exceed 40 MPH attm. Thursday, gusty winds will 
become northerly behind the 'back door slider' trough axis, with the 
downsloping component of the winds not impacting temperatures behind 
the dry frontal boundary pushing south through our area Thursday 
afternoon. Another round of shortwave ridging Friday will 
temperatures jump around 5 degrees into the low/mid 70s inland and 
low to mid 60s along the coast, and more gradual warming through the 
weekend.

&&

.AVIATION...
(12Z TAFS)
Issued at 435 AM PDT Sun Apr 12 2026

Scattered showers continue and increase in frequency into the mid 
morning with winds becoming more moderate to breezy. Scattered to, 
at times, broken low clouds linger through the morning with more 
coverage from mid-level clouds through the day. Winds become more 
moderate to breezy as shower chances increase into the mid morning 
with some slight chances for isolated storms possible. Storm chances 
erode into the evening with winds reducing and showers becoming 
lighter and spottier. Shower activity ends into the night for the 
North Bay, but the rest of the region will see shower activity 
linger into Monday morning.

Vicinity of SFO...Expect mostly mid level clouds through the day. 
Light to moderate southerly winds with passing showers last through 
the mid morning before breezier southwest winds build. This increase 
in winds will come along with increasing shower chances and slight 
chances for storms. Showers and storm chances reduce into the 
afternoon and evening. Expect gusts to fall off in the mid-evening 
and winds continue to reduce into the night. Shower activity will 
linger into early Monday, but exits as moderate northerly winds 
arrive.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Scattered shower chances increase onto the 
mid morning with prevailing mid-level clouds and scattered lower 
clouds. Winds become more moderate to breezy into the late morning 
and early afternoon. Shower chances and winds reduce into the 
evening. Winds remain light into the night, but shower activity 
increases slightly into the late night and lasts beyond the TAF 
period. 

&&

.MARINE...
(Today through Friday)
Issued at 435 AM PDT Sun Apr 12 2026

Showers and isolated storms move through the waters through the
day with lingering showers possible into early Monday. Showers
and storms could provide locally strong and gusty winds.
Widespread breezy winds begin to ease into the evening and become
lighter into the night. Winds continue to ease and seas abate
into the work week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 PM PDT this afternoon for Mry Bay-
     Pt Arena to Pt Reyes 10-60 NM-Pt Reyes to Pigeon Pt 0-10 nm-
     SF Bay N of Bay Bridge.

     Small Craft Advisory until 9 AM PDT this morning for Pigeon Pt 
     to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

     Small Craft Advisory until 9 PM PDT this evening for Pigeon Pt 
     to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...JM
LONG TERM....JM
AVIATION...Murdock
MARINE...Murdock

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Prepared by Boulder-Creek.com Weather at: Sun Apr 12 08:30:02 PDT 2026
From the National Weather Service