835
FXUS66 KMTR 120010
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
510 PM PDT Sat May 11 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 245 PM PDT Sat May 11 2024

Warm temperatures persist through the weekend, with mostly clear
skies expected. Stratus will create cloudy conditions for areas
near the Bay and coastline. Patchy fog possible near the Monterey
Bay and San Mateo coastlines early tomorrow morning. Warm
temperatures and low heat risk persist through the upcoming work
week.

&&

.SHORT TERM...
(This evening through Sunday)
Issued at 245 PM PDT Sat May 11 2024

Its another beautiful May day with warm temperatures in the upper
80s expected throughout most inland areas today (perhaps a few low
90s scattered here and there), with mid to upper 60s expected for
highs along the coast through the weekend. Clear skies prevail
through much of the forecast period, though coastal stratus and fog
will impact much of the coastline overnight as stratus trickles
inland. Areas around the Monterey Bay, Salinas Valley, SF Bay, and
Sonoma coast are likely to see overcast skies tonight as a result of
this stratus, thereby reducing any chances of aurora viewing. Yep,
that`s right, you heard that correctly! Another chance for viewing
the Aurora Borealis will be possible tonight for areas that remain
clear, namely areas further inland away from the coastline or higher
in elevation above the fog and stratus if you live in a more coastal
zone. However, keep in mind that it is only a chance! Although the
ongoing increased solar activity increases our chances of seeing the
auroras this far south, it is not by any means a guarantee. So cross
your fingers and hope for the best! That being said, how about a few
aurora-viewing tips?

-Look to the northern horizon.

-Go to a very dark area where there is little cloud cover and little
light pollution. Ideally, a more rural area away from city lights.

-Take a few minutes to sit in the darkness and let your eyes adjust.
If the auroras are to be seen, you`ll spot them best after waiting 5-
10 minutes as your eyes will be better attuned to pick up any dim
lights, such as the auroras.

-If you still cannot see them after letting your eyes adjust, try
using a long exposure camera, or a phone camera on the nighttime
setting. If your eyes don`t pick it up first, your iphone (or
android) surely will!

Although we in this particular office do not predict space weather
(just Earth weather!), for further information about what is causing
these auroras, we can point you to the right people to answer those
questions. For further information about the chances of seeing the
Aurora Borealis and the current geomagnetic storm, please take a
look at the Space Weather Prediction Center`s social media pages
(@NWSSWPC) or visit their web page at spaceweather.gov .

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 245 PM PDT Sat May 11 2024

Warm temperatures continue through much of the upcoming work
week, though cool off towards the latter half by a few degrees to
reach more seasonable temperatures. Expect high temps to be
predominantly in the low to mid 80s for interior regions, with
upper 50s and lower 60s along the coast line. Heat Risk is
expected to be low for most regions, with only the most sensitive
populations at risk for any heat-related illnesses. Nighttime lows
will be comfortable in the low to mid 50s for most regions.
Current CPC outlook places our region the next 6-10 days leaning
slightly above normal for temperatures.

&&

.AVIATION...
(00Z TAFS)
Issued at 510 PM PDT Sat May 11 2024

VFR transitioning to MVFR-LIFR overnight. Widespread stratus is
expected to return inland at all sites except LVK overnight. Similar
to last night, the marine layer will be fairly shallow with forecast
vertical wind profiles generally showing more moist air below 1500
feet and drier air above it. SFO, OAK, and SJC are leaning towards
MVFR with stratus heights between 1000-1500 feet. STS, APC, MRY, and
SNS are leaning more towards LIFR to IFR heights between 300-700
feet with LIFR heights becoming more likely by mid-morning around
12Z. At this time, weaker, variable winds and higher RH values are
expected by mid-morning which could support fog development
particularly at STS, MRY, and SNS. VFR conditions will return by
late morning with most guidance suggesting 17-19Z as the general
timeframe for clearing. Moderate NW winds will return during the
afternoon with stratus looking to return just after the end of this
TAF period.

Vicinity of SFO...VFR transitioning to MVFR overnight. Moderate NW
winds will weaken and become more westerly overnight. Widespread
stratus is expected to move inland tonight with MVFR conditions
expected by mid-morning. Most models show stratus moving in along
the coast and into the SF Bay earlier in the morning before filling
in over SFO. Continued stratus arrival at 12Z due to this pattern
but if stratus fills in faster an arrival time closer to 09-10Z may
be possible. Moderate confidence that stratus farther inland will be
closer to 1000-1500 feet but, given the shallow nature of the marine
layer, a lower ceiling developing is not out of the question. Will
continue to monitor and adjust as needed for the next TAF issuance.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR transitioning to LIFR overnight.
Similar to last night, a shallow marine layer will keep stratus
ceilings fairly low with heights between 300-700 feet possible. Fog
becomes more likely heading into the mid-morning hours (11-12Z) as
weaker, variable winds and increased RH values prevail. If fog does
develop, visibilities are likely to drop below 1SM. Conditions will
improve by late morning with moderate NW winds and VFR through the
end of the TAF period expected.
&&

.MARINE...
(Tonight through next Friday)
Issued at 510 PM PDT Sat May 11 2024

Widespread stratus continues over the inner coastal waters and is
expected to spread over the majority of the inner and outer
coastal waters overnight into tomorrow morning. Fair weather and
moderate northwesterly breezes and the occasional fresh gusts
continue through the end of the weekend. Winds begin to  increase
Monday as surface high pressure over the Eastern Pacific  Ocean
builds and moves east, keeping things dry with northwest  winds
increasing to a fresh breeze, particularly over the outer  waters,
North Bay Coast, and Big Sur Coast. For the Big Sur Coast, a
coastal jet looks to develop beginning Sunday through the mid work
week. Significant wave heights will also begin building as a
result at the start of next week, reaching maximum heights of
12-15 feet, before diminishing by the late work week.

&&

.BEACHES...
Issued at 719 PM PDT Fri May 10 2024

Long period southwest swell will lead to slightly elevated chances
for sneaker wave and rip current development this weekend.
Conditions are expected to stay below Beach Hazards Statement
criteria as swell height will only be between 1-2 feet. However, in
light of anomalously warm temperatures and increased likelihood of
people traveling to the coast, visitors to the beach should remember
to take safety precautions to prevent being caught by an unexpected
large wave and to never turn your back on the ocean.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...None.
&&

$$

SHORT TERM...AC
LONG TERM....AC
AVIATION...Kennedy
MARINE...Kennedy

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