892
FXUS66 KMTR 091711
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1011 AM PDT Tue Jul 9 2024

...New AVIATION...

.SYNOPSIS...
Issued at 404 AM PDT Tue Jul 9 2024

Heat continues this week with another warm up late week. Temps
expected to peak Thursday for most. Excessive Heat Warning
continues for interior Monterey and San Benito, while Heat
Advisories go into effect Wednesday for inland areas throughout
the rest of the region. Cool down on the way for the weekend.

&&

.UPDATE...
Issued at 907 AM PDT Tue Jul 9 2024

Satellite imagery shows extensive stratus coverage inland across
the North Bay valleys, the northern San Francisco Bay region, and
around Monterey Bay into the northern Salinas Valley. Stratus will
pare back to the coastal regions through the rest of the morning,
with temperatures continuing on pace for a cooler day today than
yesterday. The main focus continues to be the significant warm up
tomorrow into Friday. Some model output is beginning to show
convective chances later this week across the Sierras and the
mountains of the North Coast, but at this time, convective
probabilities across the Bay Area and Central Coast remain very
low.

DialH

&&

.SHORT TERM...
(Today and tonight)
Issued at 404 AM PDT Tue Jul 9 2024

Slight reprieve from the excessive heat today for most areas.
Starting the day with robust marine stratus coverage for coastal
and low-lying areas, coming in a bit faster overnight tonight
compared to last night...a sign of things to come. Most locations
shave off 4-6 degrees from yesterday`s highs as a shortwave
trough embedded in the ridge temporarily deepens the marine layer,
reinforcing the aforementioned marine stratus for the overnight
periods. By later tonight, the shortwave trough lifts inland and
becomes rather diluted while the ridge builds further and 500 mb
heights rise once again.

&&

.LONG TERM...
(Wednesday through Monday)
Issued at 404 AM PDT Tue Jul 9 2024

With the ridge building through midweek, Wednesday starts what we
expect to be the last major peak of this heat wave. Temperatures
look to peak Thursday, with highs on par with what we`ve already
seen over the past several days. Far inland areas 100-110, lower
elevation areas more near the bays ranging from 85-100, coastal
areas mid-60s to lower 80s. Heat Advisories are in effect for
inland areas from Wednesday through Friday, while the Excessive
Heat Warning for interior Monterey and San Benito continues today
through Friday.

A more substantial cool down is expected this weekend as the ridge
finally begins to migrate eastward, and a deep upper low forms in
the Gulf of Alaska. This deeper trough pattern over the EPac
should help to deepen our marine layer further and brings temps
back down to normal territory across the region by Monday.

&&

.AVIATION...
(18Z TAFS)
Issued at 1010 AM PDT Tue Jul 9 2024

A mix of LIFR to MVFR conditions across the region this morning,
except for KLVK where VFR conditions prevail. Stratus will
mostly retreat to the coast by 18-21Z with VFR conditions beyond
that time frame. Breezy winds are expected this afternoon with
strongest gusts at KSFO with gusts up to 24 kt. Expecting somewhat
of an early return of stratus tonight, generally in the 01-03Z time
frame. However, expecting similar CIGs and VSBYs as this morning.

Vicinity of SFO...CIGs improve here within the next few hours
leading to VFR conditions throughout the evening. Moderate northwest
winds return during the afternoon with gusts up to 24 kts currently
expected. Weaker winds and overcast conditions return by the late
evening with IFR conditions to persist through mid-to-late tomorrow
morning with clearing expected thereafter.

SFO Bridge Approach...Clearing has occurred and winds will be weaker
over the approach. Otherwise, similar to SFO.

Monterey Bay Terminals...KSNS has cleared this morning and KMRY will
soon follow. West to northwest winds continue through the TAF period
becoming more moderate during the afternoon before weakening
overnight. Stratus is expected to return by the late evening hours
and persist into tomorrow morning.

&&

.MARINE...
(Today through Sunday)
Issued at 907 AM PDT Tue Jul 9 2024

Moderate west to northwesterly winds continue into Tuesday with
the occasional fresh gust possible over the outer coastal waters.
Winds strengthen heading into Wednesday with fresh to strong gusts
becoming more widespread over the coastal waters. Beginning mid-
week and continuing through the late weekend, significant wave
heights will build to between 10 to 13 ft on average over the
outer coastal waters. Portions of the northern outer coastal
waters will see wave heights peak between 13 to 15 feet during the
late week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory from 11 AM Wednesday to 8 PM PDT Friday for
     CAZ502>504-506-508-510-512>516-528.

     Excessive Heat Warning until 8 PM PDT Friday for CAZ517-518.

PZ...Small Craft Advisory from 9 PM this evening to 9 PM PDT
     Wednesday for Pt Arena to Pt Reyes 10-60 NM.

     Small Craft Advisory from 9 AM to 9 PM PDT Wednesday for Pigeon
     Pt to Pt Pinos 10-60 NM.

&&

$$

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

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