Walnut Heights, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

050
FXUS66 KMTR 221912
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1112 AM PST Sat Feb 22 2025

...New SYNOPSIS, SHORT TERM, LONG TERM...

.SYNOPSIS...
Issued at 1111 AM PST Sat Feb 22 2025

Chance of very light rain in the North Bay tonight into Sunday and
again on Monday. Otherwise, dry and warm through the middle of next
week. Chance of rain returns later next week with a cutoff low
approaching the state, although details are still highly
uncertain.

&&

.SHORT TERM...
(This afternoon through Sunday)
Issued at 1111 AM PST Sat Feb 22 2025

Satellite imagery reveals coastal stratus lingering in the North Bay
and San Mateo Peninsula coastlines, while scattered cirrus persists
over much of the region. If there is anything vaguely exciting about
the short-term forecast for our region, it`s found up in the
northern fringes of Sonoma and Napa Counties. A plume of moisture is
impacting the Pacific Northwest, with the Eureka radar also showing
rain just offshore of the North Coast. The edges of the moisture
plume could bring light rain to the northern regions of Sonoma and
Napa counties beginning tonight into Sunday. Emphasis on light rain,
with the rainfall totals only around a few hundredths of an inch at
most.

Elsewhere in the region, the big story is dry and warm weather
through the weekend. Highs today range from the low to mid 70s today
in the inland valleys to the middle to upper 60s closer to the coast.
The low temperatures are also inching upwards for Sunday morning,
ranging from the middle 40s to the lower 50s in the lower
elevations, while Sunday`s highs reach the upper 70s across the
southern Salinas Valley, generally remaining similar to today`s
elsewhere.

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 1111 AM PST Sat Feb 22 2025

Another round of light rain comes into the North Bay on Monday, with
an upper level low off the Pacific Northwest becoming more defined
in the model output since yesterday. The main impacts to the
forecast are a slight increase in rain totals in the North Bay, to
around a tenth of an inch in favored locations in the Sonoma coastal
ranges, and a dip in temperatures across the region. Monday`s highs
reach the lower 60s in the North bay valleys, the upper 60s the
middle 70s in the inland valleys elsewhere, and the lower to middle
60s along the coast. As the disturbance passes, upper level ridging
returns to the region and resumes our warming trend, with high
temperatures in the inland valleys reaching the middle to upper 70s
by Wednesday.

By the middle of the week, a trough moving through the northern
Pacific deepens and cuts off as it approaches the state. At this
point, significant differences between models, and among the
ensemble solutions from the models, make the forecast highly
uncertain. Looking at the ensemble means, the American GEFS model
places a weaker low through the Central Coast by Thursday, the
Canadian GEPS model places an even weaker low around the same place
and timeframe, while the European ECMWF model further deepens the
low, places it closer to southern California, and delays its impact
to Friday. The ensemble model cluster analysis further supports
these claims with the European ensemble members tending to support a
fully cut off low off the coast of California on Thursday, while the
American ensemble members supporting a broader trough or weaker
cutoff low that gets closer to the coast, and the Canadian ensemble
members tending to support solutions that more resemble a shortwave
trough. At this point, there is a chance for rain late Wednesday
through early Friday, but anything more specific than that would be
beyond the current state of the forecast certainty. Expect further
refinements to the forecast through the next few days.

&&

.AVIATION...
(18Z TAFS)
Issued at 925 AM PST Sat Feb 22 2025

Fairly high confidence of VFR conditions to persist through the day
and into Sunday morning. However, lower visibilities/ceilings around
KHAF this morning, clearing by early afternoon only to return once
again Sunday morning due to proximately to the coast. Also, KSTS may
briefly see fog and low ceilings Sunday morning. Otherwise, light
winds this morning will become onshore this afternoon and into the
early evening before once again becoming light/variable. Onshore
winds return Sunday afternoon.

Vicinity of SFO...VFR. Mainly high clouds streaming in across the
region this morning and will likely continue into Sunday morning.
Onshore winds increase by early afternoon, yet with no notable
gusts. Very low probability of low ceilings Sunday morning, will
cover with SCT low level clouds.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR. FEW/SCT high clouds streaming across
the region from the west-northwest. Onshore flow returns this
afternoon. Winds go light/variable late this evening with drainage
winds at KSNS early Sunday morning.

&&

.MARINE...
(Today through Thursday)
Issued at 838 AM PST Sat Feb 22 2025

Winds and sea heights will remain relatively calm into early next
week. A new, moderate northwesterly swell enters the waters by
Tuesday of the upcoming week, causing seas to build up to 10 to
12 feet.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&

$$

SHORT TERM...DialH
LONG TERM....DialH
AVIATION...RGass
MARINE...RGass

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