157
FXUS66 KMTR 020519
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1019 PM PDT Wed May 1 2024

...New AVIATION...

.SYNOPSIS...
Issued at 107 PM PDT Wed May 1 2024

A ridge of high pressure will keep conditions mild to warm across
the region throughout late week. Breezy onshore winds will keep
temperatures cooler near the coast. Wet, unsettled conditions
returning Friday night into Saturday, much cooler inland Saturday.
Unseasonably cool daytime highs continuing into early next week then
gradually warming by the middle of the week.

&&

.UPDATE...
Issued at 850 PM PDT Wed May 1 2024

A fairly gusty day across the Bay Area and Central Coast with a few
coastal and higher elevation sites seeing gusts between 30-35 mph.
Gusty winds look to continue through the weekend with stronger winds
extending farther into inland valleys beginning Saturday as a low
pressure system moves inland. HREF continues to suggest minimal
cloud cover overnight with only few to scattered high level clouds
possible. Warm, dry conditions to continue through the end of the
week with highs in the mid to upper 70`s inland tomorrow and upper
50`s to lower 60`s along the coast. Guidance continues to indicate
that light precipitation is possible this weekend.

Overall forecast remains on track.

&&

.SHORT TERM...
(This evening through Thursday)
Issued at 107 PM PDT Wed May 1 2024

Dry weather conditions prevail tonight with temperatures falling
into the mid-to-upper 40`s to lower 50`s regionwide. Only expecting
low clouds near the Monterey Peninsula, if at all, as dry conditions
remain aloft. By sunrise, any low clouds that do develop with
quickly dissipate.

Thursday will see stronger northerly winds out over the ocean, peaks
near the coast, and inland higher terrain with gusts up to 45 mph
(gale force out over the ocean). Temperatures will likely reach the
60`s near the coast with mid-to-upper 70`s to near 80F inland.
Again, clear sky conditions are expected to persist.

&&

.LONG TERM...
(Thursday through Tuesday)
Issued at 133 AM PDT Wed May 1 2024

Dry Thursday and Friday, increasing clouds Friday night with rain
developing over the North Bay, rain spreading southeastward across
much of the rest of the forecast area Saturday. It`ll turn noticeably
cooler especially inland Saturday with daytime highs Saturday 10F to
18F cooler inland compared to Friday`s forecast highs.

In the last 12-24 hours global and mesoscale models are more in line
focusing on the arrival of a cold core low pressure system from the
Bering Sea/Aleutian Islands arriving in northern California Friday
night and Saturday. The southeastward trajectory takes it across
cooler than normal sea surface temperatures (negative phase PDO)
at least somewhat minimizing maritime thermal modification along
the way and for maintenance/development it`ll travel through a long
wave trough on the West Coast. The low will brush by and tap higher
levels of water vapor extending far north of Hawaii, however the
low is forecast to move through our forecast area retaining a strong
mid-latitude influence. Recent precipitable water values on the GFS
have been 1.00" to 1.10" for Saturday, not far from the max moving
average on Oakland upper air sounding climatology in early May.
Model forecast rainfall amounts vary from 0.25" to 0.70" North
Bay, 0.15"-0.25" low elevations to 0.40" hills/mountains elsewhere
across the Bay Area to around 0.10" interior north Central Coast
to 0.33" Big Sur Coast. Wet and cooler weather Saturday, gusty
northwest winds over the coast temporarily subsiding with the
passage of a surface cold front/trough. Dry weather returns
Sunday. The surface pressure pattern looks favorable for gusty
northwest winds redeveloping over the coastal waters beginning
next Tuesday. Daytime highs gradually warming by the middle of
next week.

&&

.AVIATION...
(06Z TAFS)
Issued at 1019 PM PDT Wed May 1 2024

Generally VFR into Thursday, with breezy northwest winds gusting to
20-25 knots developing Thursday afternoon. Some LLWS concerns,
chiefly in the North and East Bays, through the night into Thursday
morning. Expect stratus to fill towards and at the immediate
coastline through Thursday evening, as a trough approaches the
region.

Vicinity of SFO... VFR through the TAF period. West-northwest winds
diminishing through the night, then building again on Thursday with
gusts to 30 knots. A low confidence (20-30% probability) that wind
gusts exceed 35 knots at the terminal. Model output shows some
stratus streaming through the Golden Gate and San Bruno Gap, but
confidence is low, with OAK and SJC having slightly higher
probabilities for MVFR-IFR ceilings.

SFO Bridge Approach... Similar to SFO.

Monterey Bay Terminals... VFR through Thursday afternoon, with
westerly winds building on Thursday, gusting to 25 knots. IFR-LIFR
stratus builds at the coast and across the Monterey Bay region
Thursday evening.

&&

.MARINE...
(Tonight through next Tuesday)
Issued at 850 PM PDT Wed May 1 2024

Strong winds are expected to continue through Friday, with gale
force gusts of 40 to 45 knots possible. Strong winds will result
in hazardous seas and steep wind waves with significant wave
heights reaching 12 to 16 feet in the outer waters. Conditions
gradually improve over the weekend and into next week as winds
begin to ease. Rain chances begin early Saturday as a trough
descends over the region.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM Thursday to 3 AM PDT Friday for
     Mry Bay.

     Gale Warning until 9 PM PDT Thursday for 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 until 9 AM PDT Thursday for Pigeon Pt to Pt
     Pinos 0-10 nm.

     Gale Warning from 9 AM Thursday to 3 AM PDT Friday for Pigeon Pt
     to Pt Pinos 0-10 nm.

     Gale Warning until 3 AM PDT Friday for Pigeon Pt to Pt Pinos 10-
     60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

UPDATE...Kennedy
SHORT TERM...RGass
LONG TERM....Canepa
AVIATION...DialH
MARINE...Murdock

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