625
FXUS66 KMTR 072016
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
116 PM PDT Tue May 7 2024

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

.SYNOPSIS...
Issued at 116 PM PDT Tue May 7 2024

A warming trend begins Wednesday as offshore winds develop, with a
Wind Advisory for the interior North Bay on Wednesday morning.
Warmest temperatures are expected Thursday and Friday before a
slight cooldown into the early part of next week.

&&

.SHORT TERM...
(This evening through Wednesday)
Issued at 116 PM PDT Tue May 7 2024

Clear skies throughout the day today with little to no stratus
development this evening and overnight. High temperatures today
range from the mid 50s to low 60s on the coast, the upper 60s to
lower 70s on the Bayshore, and into the mid to upper 70s in the
interior valleys. Breezy northwest winds will develop this
afternoon, gusting up to 20 to 25 miles per hour in the ridgelines
and passes. Overnight lows will generally range from the mid 40s to
the lower 50s, with some of the most interior regions seeing lows in
the lower 40s.

A warming trend begins Wednesday, with a ridge building over the
northeast Pacific expanding into the Pacific Northwest, interacting
with a piece of an upper level low over the Northern Plains that
regresses over the Rocky Mountains and breaks off into a weak cut-
off low over the Great Basin. The end result is that offshore flow
will start to develop through Wednesday, with the higher elevations
and North Bay being the first to experience the wind shift. A Wind
Advisory is now in effect for the North Bay interior mountains and
valleys from 1 AM to 11 AM on Wednesday, for sustained winds of 20
to 30 miles per hour and gusts up to 45 miles per hour in the higher
elevations. The rest of the region should see wind gusts topping out
around 20 to 25 miles per hour. High temperatures on Wednesday range
from the low to mid 60s along the coast to the upper 70s to lower
80s in the interior valleys.

Despite the breezy offshore winds and the warming trend, very little
fire danger is expected, with moist fuels mitigating fire weather
concerns throughout the region.

&&

.LONG TERM...
(Wednesday night through next Monday)
Issued at 116 PM PDT Tue May 7 2024

The warming trend continues into the early part of the weekend, with
Thursday and Friday expected to be the warmest days of the event.
High temperatures range from the upper 60s to lower 70s near the
coast, to the upper 80s to lower 90s inland. With northeasterly
offshore flow continuing through Thursday, and with prior pattern
recognition of warmer temperatures in downslope areas as a result,
have increased temperatures on Thursday from the previous forecast.
The seasonably warm temperatures are causing a minor to moderate
HeatRisk, meaning that a low to moderate risk for heat related
illnesses exists for vulnerable populations (children, the elderly,
pregnant women, or those without adequate shelter or cooling), with
moderate HeatRisk values concentrated in the interior regions of the
North, East, and South Bays. For some context: downtown San
Francisco, which sees highs around the mid 60s this time of year, is
expected to top out at 81; Santa Rosa, where the seasonal average
high is in the mid 70s, is facing a high temperature of 89; and
Salinas is forecast to reach a high of 80 versus a seasonal average
high of 68.

With the significant warm up expected for the rest of the week,
here`s a reminder of 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.

The heat should start to abate on Sunday as onshore flow returns to
the region, but temperatures warmer than the seasonal averages are
expected to continue for the foreseeable future, with CPC products
stating that temperatures above seasonal averages continue into the
third week of May.

&&

.AVIATION...
(18Z TAFS)
Issued at 1053 AM PDT Tue May 7 2024

VFR through the TAF period with breezy northwest winds continuing
into the evening with light to moderate west to northwest winds
overnight. Heading into tomorrow, gusty north to northwest winds
return as upper level ridging and surface high pressure builds. Wind
shear is expected at STS, APC, OAK, SFO, and LVK overnight. Moderate
to high confidence that VFR will prevail at all stations overnight.
HREF indicates some cloud cover in the Monterey Bay tomorrow morning
but coverage should remain few to scattered.

Vicinity of SFO...VFR through the TAF period. Breezy to gusty west
to northwest winds continue into the evening with moderate westerly
winds overnight. Gusty winds return by mid tomorrow morning with
gusts up to 22 knots possible. A few ensemble members indicate that
gusts between 25-27 knots are possible tomorrow so will keep an eye
on and adjust gusts as needed.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR through the TAF period. Moderate
northwest winds becoming gusty during the afternoon at SNS. Winds
weaken to light to moderate overnight with winds becoming more
variable at MRY. HREF guidance shows some cloud cover in Monterey
Bay but confidence is low that a ceiling will develop as upper level
conditions will be drier and the marine layer will be fairly shallow
as high pressure builds. Any cloud coverage that does develop at MRY
will be few to scattered.

&&

.MARINE...
(Today through Sunday)
Issued at 1053 AM PDT Tue May 7 2024

Strong northerly winds continue through the midweek, with gale-
force  gusts expected over the outer waters and near the Big Sur
coast.  Towards the early Thursday morning, winds slowly ease to
become  fresh to moderate. However, as a result of strong winds in
the early  portion of the week, significant wave heights will
build to heights  of 15 to 16 feet over the outer waters by mid-
week. Sea conditions  will be hazardous Tuesday and Wednesday with
gale warnings issued  for portions of the coastal waters. By the
late week into the  weekend, winds ease to become gentle,
significant wave heights  gradually diminish to 5 to 7 feet, and
dry weather continues as high  pressure dominates.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory from 1 AM to 11 AM PDT Wednesday for CAZ504-506.

PZ...Small Craft Advisory from 9 AM to 3 PM PDT Wednesday for SF Bay
     N of Bay Bridge.

     Small Craft Advisory until 9 PM PDT this evening for Mry Bay.

     Small Craft Advisory until 3 AM PDT Wednesday for Pigeon Pt to
     Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Reyes to
     Pigeon Pt 0-10 nm.

     Gale Warning until 3 AM PDT Wednesday for Pt Pinos to Pt Piedras
     Blancas 0-10 nm.

     Small Craft Advisory until 3 PM PDT this afternoon for Pigeon Pt
     to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.

     Gale Warning until 3 PM PDT Wednesday for Pt Arena to Pt Reyes
     10-60 NM.

     Gale Warning until 3 AM PDT Wednesday for Pigeon Pt to Pt Pinos
     10-60 NM.

&&

$$

SHORT TERM...DialH
LONG TERM....DialH
AVIATION...Kennedy
MARINE...Kennedy

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