FXUS66 KMTR 191853
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1153 AM PDT Sun Apr 19 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 935 PM PDT Sat Apr 18 2026
- Seasonally warm temperatures Sunday
- Cooler temperatures, beneficial rainfall, and isolated
thunderstorms expected Monday through Wednesday
&&
.SHORT TERM...
Issued at 935 PM PDT Sat Apr 18 2026
(Tonight through Monday)
Satellite imagery shows high clouds continuing to cover the Bay Area
and Central Coast tonight, which are expected to continue to push
through the region in the overnight period before steadily thinning
and scattering Sunday morning. Low temperatures tonight are expected
to hover in the middle 40s to lower 50s across the region, perhaps a
few degrees warmer than the current forecast if the high level cloud
cover is enough to inhibit radiational cooling and reflect thermal
energy back to the surface.
Today will be a day of temperatures close to the seasonal averages,
with the inland valleys reaching highs in the 70s, the Bays seeing
highs in the middle 60s to lower 70s, and the Pacific coast hovering
around the upper 50s to the lower 60s. A gentle onshore breeze with
a southwesterly component will develop during the afternoon, with
the breezy winds persisting into the night as a cold front
approaches the region.
&&
.LONG TERM...
Issued at 935 PM PDT Sat Apr 18 2026
(Monday night through next Saturday)
The focus of the seven-day outlook continues to be centered around
the cold front coming through the Bay Area and Central Coast for the
early part of the work week. Pre-frontal rain showers are expected
to arrive sometime Monday morning across the North Bay and continue
to spread southward through the day, with the main frontal band
coming through later on Monday into Tuesday morning. Behind the
front, and with the associated upper level low coming through
northern California, the newly arrived cold pool will allow for a
chance of isolated to scattered thunderstorms through Tuesday
afternoon and evening, with probabilities ranging from around 20 to
30 percent across the region. Lingering showers and chances for
isolated thunderstorms (up to 15% probability) continue through
Wednesday, and should move out of the region by Wednesday night.
Through all of this, high temperatures will dip into the lower to
middle 60s in the lower elevations to the 50s across the higher
elevations, and rain totals will range from 0.5-1.5" across the
interior valleys and most of the Bay Area and Monterey Bay regions,
to around 1.5-3" in the coastal ranges and the interior mountains of
the North Bay. This should be mostly beneficial across the region,
but some minor nuisance flooding is possible in urban and poor
drainage areas if heavy rain showers or thunderstorms develop.
As the frontal system passes, temperatures will warm slightly into a
rather dry latter part of the week, back to around the seasonal
averages rather similar to today's highs. Extended guidance from the
Climate Prediction Center leans towards temperatures and rain
totals above seasonal averages for the last week of April.
&&
.AVIATION...
(18Z TAFS)
Issued at 1152 AM PDT Sun Apr 19 2026
High clouds are building across the area with moderate winds
building into the afternoon. Winds become light into the evening and
into the night with mostly variable to southerly winds expected. The
next cold front begins to enter the region from the northwest into
the late night and early morning. Southerly winds build ahead of the
front with light prefrontal showers. Rain and winds increase along
the front with gusty southerly winds expected. Rain and winds
continue well beyond the TAF period, with increased rain rate
predicted further into Monday.
Vicinity of SFO...VFR through the TAF period. High clouds will build
through the day with moderate west to southwest winds. Winds weaken
and turn slightly more southerly into the night. Light showers arrive
along with moderate southerly winds into Monday morning. Gusty south
winds build into the late morning on monday as rain rates begin to
increase.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR through the TAF period. High clouds
continue to build into the areas with moderate to breezy winds
expected this afternoon and through the evening. Winds reduce into
the night and become light. Southeast winds begin to build at SNS
into mid Monday morning. Showers and increased winds arrived beyond
the TAF period.
&&
.MARINE...
(Today through Friday)
Issued at 1152 AM PDT Sun Apr 19 2026
Expect breezy and gusty winds to build ahead of a slow moving
cold front that arrives on Monday. Rain will accompany the cold
front starting Monday and lingering into early Wednesday. Chances
of thunderstorms will move through the waters for much of Tuesday.
Dry weather returns late in the week.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 9 PM PDT Monday for SF Bay N
of Bay Bridge.
Small Craft Advisory from 9 AM Monday to 3 AM PDT Tuesday for
Mry Bay.
Small Craft Advisory from 3 AM to 9 PM PDT Monday for 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 Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory from 3 AM Monday to 3 AM PDT Tuesday for
Pigeon Pt to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras
Blancas 0-10 nm.
&&
$$
SHORT TERM...DialH
LONG TERM....DialH
AVIATION...Murdock
MARINE...Murdock
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Prepared by Boulder-Creek.com Weather at: Sun Apr 19 12:30:02 PDT 2026
From the National Weather Service
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