223
FXUS66 KMTR 060543
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1043 PM PDT Fri Jul 5 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1232 AM PDT Fri Jul 5 2024

Dangerous heat continues inland as high pressure prevails through
the middle of next week. Red Flag Warnings remain in effect
through Saturday night, and heat hazard highlights through
Wednesday.

&&

.UPDATE...
Issued at 857 PM PDT Fri Jul 5 2024

It was hot, again. And as the marathon of heat continued today,
Oakland Downtown and King City broke their daily record highs.
Tomorrow looks like the peak of the heat for most areas before the
slow cooling trend begins. Keep finding ways to beat the heat!

-Murdock

&&

.SHORT TERM...
(This evening through Saturday)
Issued at 147 PM PDT Fri Jul 5 2024

The impressive dome of high pressure continues to slowly migrate to
the east, with near 600dm heights over NorCal, bringing record
warmth across western CONUS. Today`s temperatures will be some of
the highest yet for the heat wave, and many locations will see
another increase of 4-5 degrees tomorrow, especially inland.
Similar to last night, some low level stratus is expected to
develop near the coast later tonight and persist into early
tomorrow morning, but should mostly burn off by mid/late morning
tomorrow. Mild overnight lows will once again limit nighttime
relief from the heat for inland locations.

&&

.LONG TERM...
(Saturday night through next Thursday)
Issued at 147 PM PDT Fri Jul 5 2024

Despite only marginally lower temperatures on Sunday, the cumulative
effects of the building heat will continue to be felt into the
beginning of next week. Along with the daytime highs, the overnight
lows begin to taper downward for the first half of next week but are
still 5-10 degrees above normal for inland locations. The strong
high becomes more amplified on Monday as it works east and south
while a weak trough begins to gradually bring heights down on the
back side of the ridge across our region. This will help to bring
temperatures down, but with highs well into the 90s and low 100s
across much of our area through the extended forecast, this won`t
necessarily bring an end to the heat wave and all its impacts.
Please continue to taking the following precautions to keep
yourself, family, friends and pets safe from the heat:

Heat is the number 1 weather related killer in the United States.
Unfortunately lives will be lost during this heat wave. Follow these
tips to protect yourself, your loved ones, and your animals.

-Stay inside in an air conditioned environment between 10am and 7pm.
-Suspend unnecessary outdoor activities during the extreme heat, but
if you must be outdoors, take frequent breaks in the shade  or AC
and drink cool water.
-Know the signs and symptoms of Heat Exhaustion vs. Heat Stroke!
Heat Stroke can be deadly if not treated immediately by a medical
professional. Call 911 if you suspect someone is suffering from Heat
Stroke.
-Wear a lifejacket, swim near a lifeguard, and check conditions
before entering the water if going to a river or ocean to cool off.
Rivers and the ocean are extremely cold, and Cold Water Shock can
turn into paralysis and drowning if you are not careful.
-Use a cool and damp towel on your body if you do not have AC and
are feeling hot. Or, take a cool shower or bath.
-Do not leave kids or pets in a parked car.
-Ensure pets and livestock have access to shade and water.

&&

.AVIATION...
(06Z TAFS)
Issued at 1042 PM PDT Fri Jul 5 2024

VFR at all stations with MVFR/IFR conditions to return at OAK, MRY,
and SNS overnight. Guidance indicates some low clouds may reach STS
and APC but confidence remains too low to include in TAF. Onshore
flow is expected to persist through the period with winds becoming
light and, at times, variable overnight. Haze and smoke may be
visible from terminals, but it is not expected to result in a
reduction in flight category.

Vicinity of SFO...VFR to persist through the TAF period. Five minute
observations (as of 10PM) show a general weakening trend for winds
with chances for stronger gusts (greater than 20 knots) fully
diminishing by midnight. Moderate onshore flow continues overnight
before gusty winds up to 23 knots returns late tomorrow morning.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR becoming IFR overnight.
Onshore flow continues through the TAF period with light, at times,
variable winds overnight becoming more moderate during the day. High
confidence in LIFR CIGs and reduced visibility developing overnight
as the marine layer remains compressed below 1000 feet. Improved
conditions will return by mid-morning at both MRY and SNS.
Confidence is low that fog will develop but will continue to monitor
given persistence and highly compressed marine layer.

&&

.MARINE...
(Tonight through next Thursday)
Issued at 1042 PM PDT Fri Jul 5 2024

High pressure over the Pacific Ocean will be the dominating
feature through the period. Gentle to moderate northwesterly
breezes will prevail through the period. Significant wave heights
will build to 10-12 feet beginning Wednesday night.

&&

.FIRE WEATHER...
Issued at 940 AM PDT Fri Jul 5 2024

Red Flag Warnings remain in effect for the North Bay Interior
Mountains, East Bay Hills and Santa Cruz Mountains until 9 PM
Saturday. Red Flag Warnings are also in effect for the Santa Lucia
Mountains, San Benito County, and the Southern Salinas Valley until
9 PM Saturday as well

Despite easing surface winds, this prolonged heat wave will
continue to bring very low RH that will cure and dry the fuels.
ERC values are exceeding or approaching the max moving average for
a number of regions. Conditions are dangerous, and we urge
extreme caution. Please rethink the use of any fireworks this
year, including the safe and sane, or even those seemingly-
innocuous sparklers and pop-its. Perhaps consider not lighting
them off at all this year, and instead enjoy a professional
display in your community, or even on TV. Its not worth the risk.
Don`t Be the Spark!

&&

.BEACHES...
Issued at 1224 AM PDT Wed Jul 3 2024

Beaches will be a popular destination over the Holiday and as one
of the few places to escape the oppressive inland temperatures.
Fortunately the waves are relatively low energy, but that doesn`t
alleviate all beach safety concerns. Ocean temperatures are in
the mid-50s. This cold water may catch some off-guard. Cold water
shock can set in very quickly. Wear a life jacket, dress
appropriately, limit time in the water, swim near a lifeguard and
follow their instructions.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Excessive Heat Warning until 11 PM PDT Wednesday for CAZ502>504-
     506-510-512>518.

     Red Flag Warning until 9 PM PDT Saturday for CAZ504-512-515>518.

     Heat Advisory until 11 PM PDT Wednesday for CAZ508-528-529.

PZ...Small Craft Advisory until 3 AM PDT Saturday for Pt Arena to Pt
     Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...JM
LONG TERM....JM
AVIATION...Sarment/Kennedy
MARINE...Sarment

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