677
FXUS66 KMTR 050807
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
107 AM PDT Fri Jul 5 2024

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

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

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

&&

.SHORT TERM...
(Today and tonight)
Issued at 1232 AM PDT Fri Jul 5 2024

A touch warmer today across inland areas, but much of the same
across lower elevations and coastal areas. Day 4 of the heat wave
now, and the next couple of days look like they`ll represent our
secondary peak. Still no major synoptic driver of widespread
offshore winds, so expect the marine layer to remain mostly in
place. This is the reason many coastal areas have been largely
spared from the record-breaking and deadly heat that we are
seeing inland. Red Flag Warnings are still in effect into the
weekend. As of writing, no major incidents that we are aware of.
However, while monitoring overnight satellite, there have been
dozens of small fires and flare ups from the Delta to the South
Bay and into the Central Valley.

&&

.LONG TERM...
(Saturday through Thursday)
Issued at 1232 AM PDT Fri Jul 5 2024

I`ll start with the good news for those dealing with the heat. It
looks like we`re getting over the peak this weekend, and there has
been a consistent trend in "cooling off" late next week. The bad
news? It`s going to warm up into Saturday, and we still have a
few days of upper 90s and lower 100s to go. By Saturday, we should
see temps in northern Napa/Sonoma and far eastern Contra
Costa/Alameda approaching 110 once again, while temps in southern
Monterey County may push the 115-118 mark. These locations are
looking at temperatures 20-25 degrees above normal for this time
of year. Cluster analysis still strongly supports a ridge pattern
that promotes above average temperatures through the forecast
period, but those temps are expected to be closer to 5-10 degrees
above normal by the end of next week. At this time, we have chosen
to not extended the heat highlights beyond their current
expiration of Wednesday night.

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 1047 PM PDT Thu Jul 4 2024

VFR through the TAF period for all but the immediate coast and the
Monterey Bay. High pressure aloft is causing a very shallow marine
layer. The good news is this will only affect the coastal
terminals overnight, the bad news is the the terminals that do
have a ceiling roll in will see very low ceilings in the 200 ft
range and possible fog. These CIGS look to last into late Friday
morning but erode as widespread moderate to breezy winds return.
Winds reduce again into Friday evening.

Vicinity of SFO...VFR through the TAF period. Moderate winds last
into the night before reducing. Moderate westerly winds return
Friday afternoon with some infrequent breezes, but these winds
weaken into the night.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Winds reduce into the night as LIFR CIGS
move inland and fill over MRY, with SNS filling later into the
night. These CIGs erode in the mid to late morning as westerly
winds build. Winds reduce again into the evening with CIGs
returning later Friday night. There is also some visibility
reduction due to a combination of firework smoke and high pressure
that may get worse as the temperature drops and fog starts to
form.

&&

.MARINE...
(Tonight through next Wednesday)
Issued at 919 PM PDT Thu Jul 4 2024

Light to moderate winds persist for most areas until the end of
the week. Waves continue to reduce before breezy to gusty winds
build into Friday in the southern waters, causing hazardous
conditions for small craft.

&&

.FIRE WEATHER...
Issued at 819 PM PDT Thu Jul 4 2024

Red Flag Warnings are in effect for the Marin and Sonoma Coastal
Range until 5 AM Friday. Red Flag Warnings are in effect for the
North Bay Interior Mountains, East Bay Hills, and Santa Cruz
Mountains until 9 PM Saturday. Red Flag Warnings are in effect for
the Santa Lucia Mountains, San Benito County, and the Southern
Salinas Valley from 9 AM Friday through 9 PM Saturday.

Winds have calmed since yesterday, and are now gusting in the 15-25
mph range at higher elevations. Despite the wind improvement, 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...Coastal Flood Advisory until 5 AM PDT early this morning for
     CAZ006-506-508.

     Excessive Heat Warning until 11 PM PDT Wednesday for CAZ502>504-
     506-510-512>518.

     Red Flag Warning until 5 AM PDT early this morning for CAZ502-
     503.

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

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

     Red Flag Warning from 9 AM this morning to 9 PM PDT Saturday for
     CAZ516>518.

PZ...Small Craft Advisory until 9 AM PDT Saturday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Flynn
MARINE...Murdock

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