011
FXUS66 KMTR 030650
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1150 PM PDT Sun Jun 2 2024

...New AVIATION...

.SYNOPSIS...
Issued at 1254 PM PDT Sun Jun 2 2024

Cooler temperatures hang on through Monday with breezy daytime winds
and marine layer stratus overnight. Tuesday sees a dramatic warmup
with a Heat Advisory in effect for the inland areas through
Thursday. Temperatures will moderate towards the latter part of
the week.

&&

.UPDATE...
Issued at 842 PM PDT Sun Jun 2 2024

For the most part, another seasonably cool day around the Bay Area
and Central Coast with highs topping out in the upper 50s to 70s
along the coast/bays and 70s to mid 80s inland. Additionally, it
was a mixed bag with some sites warmer and some sites colder than
Saturday. The variability was likely tied to persistent onshore
flow and increasing high level clouds. The bigger story for the
day were the winds. The onshore gradient from SFO-SAC may have
eased a little, but still saw some impressive winds today. A
sampling of the peak winds had a few sites 50-55 mph in SF
Peninsula and East Bay Hills. Other gaps and passes weren`t as
strong, but still gusting 25-40 mph.

No real update needed in the near term. A weak cold front
currently spreading light rain across far NorCal continues to move
slowly southward. The tail end of the feature will clip the North
Bay late tonight and early Monday brining a low chance (15-20%)
of 0.01 rain. The more likely scenario will be more widespread
drizzle that may accumulate along the coast and coastal terrain.
Otherwise, the marine layer lurking over the coastal waters and
immediate coast will make its nightly march inland.

MM

&&

.SHORT TERM...
(This evening through Monday)
Issued at 1254 PM PDT Sun Jun 2 2024

Coastal stratus lingers over the western San Mateo Peninsula, with
some cloud cover slipping through the San Bruno Gap, and in the
southern Monterey Bay region. Expect the remaining cloud cover over
the SF Bay region to dissipate through the rest of the afternoon and
brief, if any, clearing for the coastal regions. Stratus returns
inland tonight with the potential for gloomy skies through Monday,
as the fringes of a cold front that impacts the Pacific Northwest
come through the region. High resolution model output is showing
some chance (10-20% PoP) for showers in the Sonoma coastal ranges,
and coastal drizzle elsewhere, but accumulations are expected to
remain very light, up to a few hundredths of an inch at most.

Northwest winds are picking up around the region and gusts will top
out at 20 to 30 miles per hour across the gaps and passes. These
winds are expected to diminish tonight before picking up again on
Monday. Today`s highs will be in the upper 50s to lower 60s along
the Pacific coast, the mid 60s to lower 70s in the Bayshore, and
generally in the upper 70s to lower 80s across the inland valleys.
The North Bay and southern Monterey County valleys will see highs
rising into the mid to upper 80s. Low temperatures tonight will
hover in the mid 50s to lower 60s, and Monday`s highs should be
similar to today`s, except in the North Bay where the frontal
influence will drop high temperatures to the upper 70s to around
80.

&&

.LONG TERM...
(Monday night through next Saturday)
Issued at 1254 PM PDT Sun Jun 2 2024

Tuesday sees a pattern change as a subtropical high building in the
eastern Pacific comes into the region, warming temperatures to well
above the seasonal averages. A Heat Advisory is in effect for
Tuesday through Thursday for the interior North Bay and East Bay,
and Wednesday through Thursday for the South Bay and interior
mountains of the Central Coast, where high temperatures rise into
the 90s to the lower 100s and lows hover in the low to mid 60s,
perhaps around 70 in the warmest locations. There`s still a fair bit
of uncertainty in how the warmth will translate to the coast, in
particular how the marine layer and onshore winds will impact
coastal temperatures. The current forecast calls for temperatures in
the upper 70s to lower 80s along the Bayshore and the mid 60s to
lower 70s along the Pacific coast.

Moderate HeatRisk is expected for the inland North Bay, the East and
South Bays, and the inland Central Coast through Thursday, meaning
that there`s a moderate risk of heat-related illnesses for sensitive
populations (children, the elderly, pregnant women, those with
certain medical conditions, or anyone working outside without
cooling or hydration). In addition, we`re also starting to see major
HeatRisk in some areas of the North Bay valleys and far eastern
Contra Costa county on Tuesday, corresponding to a major risk of
heat-related illnesses to anyone without effective cooling, adequate
hydration, or both. Here are some heat safety tips:

* Stay hydrated and drink plenty of fluids.
* Wear lightweight, light-colored clothing.
* Reduce time spent outdoors or stay in the shade.
* Never leave people or pets unattended in vehicles.
* Use sunscreen if going to the coast or the pool.

A gradual cooling trend is expected to begin later in the week as
the high starts to crawl towards the east, with the large scale
pattern hinting at a possible southerly wind reversal. By the
upcoming weekend, high temperatures are expected to moderate to the
low to mid 80s for the inland valleys and the upper 50s to mid 60s
closer to the coast.

&&

.AVIATION...
(06Z TAFS)
Issued at 1150 PM PDT Sun Jun 2 2024

Coastal stratus will continue to push inland through much of the
night, bringing low IFR CIGs for many terminals. Models do suggest
CIGs even dipping into LIFR territory, though confidence on this is
only moderate for the SF Bay region. However, with an approaching
ridge, this could lead to compression, thereby lowering CIGs, so it
is not entirely out of the question that CIGs could go LIFR.
Therefore, have decided to include LIFR CIGs in select TAF sites for
now, though this will be something to keep an eye on through the
night. Into the afternoon tomorrow, moderate westerly winds return,
though gusts will likely be isolated to coastal terminals, reaching
about 20-25 knots. Clearing to VFR is expected to be late for most,
occuring in the afternoon as winds begin to increase.


Vicinity of SFO...Currently IFR. Moderate confidence in becoming
LIFR into the later overnight hours. High clouds will also be
present through the morning. Late clearing of stratus is expected in
the afternoon time, VFR but with SCT low clouds as winds increase
and gust to around 30 knots out of the west. Clouds are anticipated
to continue to dissipate through the end of the TAF period leading
to widespread VFR.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...IFR conditions persist through much of the
night, becoming LIFR in the early morning of Monday. Stratus will
begin to lift again near sunrise, eventually becoming MVFR in the
late afternoon. Not expecting clearing to VFR tomorrow, so have left
CIGs in the TAF. Westerly winds breezy in the afternoon tomorrow,
then easing into the late night.

&&

.MARINE...
(Tonight through next Friday)
Issued at 442 PM PDT Sun Jun 2 2024

The gradient between subtropical high pressure over the Pacific
and lower pressure over the Intermountain West is maintaining a
fresh to strong NW breeze. Buoys are reporting wind gusts as high
as 30 kts, on an increasing trend this evening. These conditions
will last well into the night. Moderate wave heights will persist
through Monday night before rough seas arrive mid-week.

&&

.CLIMATE...
Issued at 127 AM PDT Sat Jun 1 2024

Record high temperatures at the long term climate stations for
June 4th and 5th:

Station             June 4th             June 5th

Santa Rosa          98 in 1949           102 in 1926
Kentfield          101 in 1981           102 in 1926
Napa               102 in 1981           105 in 1903
Richmond            90 in 1955            86 in 1983
Livermore          105 in 1960           104 in 1926
San Francisco       92 in 1949            95 in 1883
SFO Airport         92 in 1955, 1949      89 in 1972
Redwood City       100 in 1981            97 in 2002, 1972
Half Moon Bay       71 in 1955            74 in 1958
Oakland downtown    96 in 1981            87 in 2002
San Jose            98 in 1904           100 in 1926
Salinas Airport     92 in 1949            87 in 1949
King City          102 in 1981, 1957     105 in 1926

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory from 8 AM Tuesday to midnight PDT Thursday night
     for CAZ503-504-506-510-515.

     Heat Advisory from 8 AM Wednesday to midnight PDT Thursday night
     for CAZ513-514-518.

PZ...Small Craft Advisory from 3 PM to 9 PM PDT Monday for Mry Bay.

     Small Craft Advisory until 3 AM 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 PM Monday to 9 AM PDT Tuesday 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.

     Small Craft Advisory from 3 PM Monday to 3 AM PDT Tuesday for
     Pigeon Pt to Pt Pinos 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 3 AM PDT Tuesday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...DialH
LONG TERM....DialH
AVIATION...AC
MARINE...Flynn

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, Twitter, and YouTube at:
www.facebook.com/nwsbayarea
www.twitter.com/nwsbayarea
www.youtube.com/nwsbayarea