772
FXUS66 KMTR 211955
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1255 PM PDT Fri Jun 21 2024

...New SYNOPSIS, SHORT TERM...

.SYNOPSIS...
Issued at 1253 PM PDT Fri Jun 21 2024

A Heat Advisory comes into effect on Saturday for the interior
regions with a moderate risk of heat-related illnesses.
Temperatures moderate through the early part of next week, but
remain warm across the interior.

&&

.SHORT TERM...
(This evening through Saturday)
Issued at 1253 PM PDT Fri Jun 21 2024

Tonight, temperatures will generally cool into the mid 50`s for most
locations away from the immediate coast with some upper 40`s in
those locations. However, warm temperatures will persist across the
higher elevations where temperatures will only dip into the upper
60`s to upper 70`s. Stratus will also return to the region this
evening, yet will penetrate less inland overnight as high pressure
compresses the marine layer.

Temperatures on Saturday will be the warmest of the week with
maximum temperatures reaching 105 degrees across the warmest inland
areas to mid 90`s in the interior valleys. This is where we have a
Heat Advisory in effect where HeatRisk reach moderate levels, across
the interior and higher elevations in the Santa Lucia Range. Near
the coast and areas just inland, mid 70`s to mid 80`s for the
Bayshore, and the 60`s and low 70`s along the Pacific coast as a
shallow marine layer remains in place.

Much of the interior is expected to see Moderate HeatRisk tomorrow,
most notably the interior East Bay, South Bay, and southern Salinas
Valley. This means that there is a risk of heat-related illnesses
for most people sensitive to heat, including children, the elderly,
pregnant women, those working or living outside, and those with
certain medical conditions. Here are 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, the elderly, or pets unattended in vehicles.
* Use sunscreen if going to the coast or the pool.


&&

.LONG TERM...
(Saturday night through Thursday)
Issued at 1231 AM PDT Fri Jun 21 2024

Sunday should be noticeably cooler with an upper level trough to
our west beginning to promote stronger onshore flow. High
temperatures will drop into the mid 80s to the low 90s in the
interior valleys (perhaps close to 100 in the warmest spots), the
70s into the lower 80s along the Bayshore, and the upper 50s to
the 60s along the coast. Expect these temperatures to continue
into the next work week. Beyond that, CPC outlooks continue to
suggest chances for temperatures above seasonal averages (around
33-50% probability) and precipitation near or below seasonal
averages into the first few days of July.

&&

.AVIATION...
(18Z TAFS)
Issued at 1057 AM PDT Fri Jun 21 2024

Deep marine layer this morning allowing ample stratus coverage.
Expecting all terminals to clear to VFR through the remainder of
the day today, with stratus returning in the evening hours for
coastal sites. Winds today follow the typical diurnal onshore
pattern. Marine layer compresses tonight and Saturday under a high
pressure ridge, leading to LIFR/IFR cigs and FG impacts at coastal
terminals early Saturday morning. All sites clear to VFR by mid
Saturday morning with high confidence of VFR through the day.

Vicinity of SFO...Clear and remaining VFR through the day. Gusty
NW winds 20-25 kts this afternoon, diminishing by about 05-06Z.
Some marine stratus will make its way into the Bay overnight.
However, not currently expecting enough coverage for a cig at the
terminal (low-medium confidence).

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Clouds pulling back to the coastline and
VFR through the afternoon. Expecting IFR cigs to return between
01-03Z (medium-high confidence), lowering to LIFR during the
overnight period. Some FG impacts as well for terminals more near
the coast with vis as low as 1/4SM. Conditions are expected to
improve rapidly mid Saturday morning.

&&

.MARINE...
(Today through Wednesday)
Issued at 845 AM PDT Fri Jun 21 2024

Moderate to fresh northwesterly winds prevail into the weekend
with strong near gale forced winds over the northern outer waters.
These stronger gusts may pose hazardous for small craft.
Significant wave heights of 6-8 feet will persist until the end of
the week, then build back up to 10-12 feet over the outer waters
for the weekend, when northwest winds increase once again over
much of the waters. Light southerly swell continues to move
through the waters today, accompanied by moderate NW swell.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory from 11 AM to 10 PM PDT Saturday for CAZ504-510-
     513>518.

PZ...Small Craft Advisory until 9 AM PDT Sunday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory until 9 PM PDT Saturday for Pigeon Pt to Pt
     Pinos 10-60 NM.

&&

$$

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

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