Rip Current in California, July 20, 2022

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1033 PM PDT Tue Jul 19 2022

.SYNOPSIS...Minor fluctuations in temperatures this week, as warm
to hot conditions continue across the interior. Some minor cooling
will be possible on Friday for the inland locations, while coastal
locations continue to see just minor day to day fluctuations.
Potential for sneaker waves and dangerous rip currents this
afternoon through Wednesday evening.

&&

.DISCUSSION...as of 09:46 PM PDT Tuesday...The weather pattern
this week won't be changing drastically as we continue to sit
between low pressure over the Eastern Pacific Ocean and high
pressure hovering over the desert SW. Daytime highs will vary by a
few degrees each day. The hottest area in our CWA will continue
to be in the interior southern portions of San Benito and Monterey
counties since they are closer to the high pressure system. Once
again, Parkfield and Pinnacles Natl Park came in as our hottest
locations with 103 and 104, respectively. However, the far East
Bay regions (around Discovery Bay) reached around 100 and the
hotter interior portion of Napa County around Lake Berryessa got
into the upper 90s. Expect those hotter spots to remain so again
tomorrow as that high pressure system looks to strengthen
slightly. In addition, the 850 mb temps are forecast to increase
from around 24 degrees C today to 25 degrees C tomorrow.

Over near the coast, the marine layer has been hovering around
1000 ft deep which has done a great job at mitigating heat in the
lower elevations. Downtown San Francisco was a very mild 62, Santa
Cruz reached 79, Monterey warmed to 66, and Big Sur hit 86. Thus,
if you're on the coast or in the valleys closer to the coast or
around the bay shorelines, you should stay in the 60s to 80s
range for tomorrow.

Likely won't feel a noticeable cooldown until the end of the week
around Friday or Saturday when the low over the ocean lifts to
the NE and moves into the Pacific NW/Northern CA. However, that
cooling won't be a huge dip in temperatures, but enough to take
the edge off as we veer away from the triple digits by Saturday.

Only changes for the forecast package were to lower the minimum RH
values for tomorrow. After looking at today's observations, the
far interior had very low min RH values with many in the single
digits or teens. Since tomorrow could be a degree or two warmer in
the far interior, they'll likely be at least as dry as today if
not a touch more so adjusted the forecast to reflect this.

&&

.PREV DISCUSSION...As of 02:15 PM PDT Tuesday...Water vapor imagery
continues to show California situated between an upper level low
over the Pacific and high pressure to our east, and will remain
that way the next couple of days. As a result, expect only minor
day to day fluctuations possible in the temperatures through
Thursday, with warm to hot conditions continuing across our inland
areas. Meanwhile, nighttime and early morning low clouds and fog
will continue to prevail along the coast, helping to moderate
temperatures there as onshore flow prevails. There could once
again be some patchy dense fog during the morning commute, but it
should be brief.

The models have been hinting at the potential for more mid and
upper level moisture for Wednesday and Thursday. Although the
chance is nonzero, the brunt of it looks to remain well to our
south and east. The instability also looks minimal, favoring the
Sierra. Therefore, the likelihood of this happening is looking
less and less, but will continue to watch.

The upper level low over the Pacific will gradually lift north
over the next 24 hours and move inland across the Pacific
Northwest late Thursday into Friday. As it does this, the ridge
will be suppressed, with stronger onshore flow developing. As a
result, cooler conditions will develop across the inland areas on
Friday. Temperatures will be 3 to 6 degrees on Friday across the
inland areas, but given where we started, it will still be quite
warm. As this trough finally lifts out, high pressure will become
the dominant weather feature once again, with hot conditions
developing once again across the inland areas for the weekend and
early next week. The coast will stay near to slightly above
normal, as a shallow marine layer remains in place. Palmer

&&

.AVIATION...As of 10:30 PM PDT Tuesday...For the 06Z TAFs. Low
clouds and fog are already intruding into coastal gaps and valleys
this evening. Further inland penetration of coastal stratus is
expected overnight and into Wednesday morning. Anticipate and
earlier return of IFR/LIFR cigs across terminals located near the
coast and bays. Low clouds anticipated to scatter out around 17z-
19z Wednesday. Moderate onshore flow will persist through this
evening then diminish overnight becoming light and variable across
most terminals.

Vicinity of KSFO...Stratus is currently increasing in coverage
around the SF Bay with IFR/LIFR cigs expected soon at KSFO and
lasting through the night. Clearing expected around 17Z. Moderate
winds will ease overnight becoming light and locally variable
overnight.

KSFO Bridge Approach...Similar to SFO.

Monterey Bay...LIFR/IFR cigs encompassing the Monterey Bay area
are expected through Wednesday morning. Moderate onshore winds
will ease overnight becoming light and locally variable overnight.
Low clouds anticipated to scatter out around 17z-19z Wednesday.

&&

.BEACHES...Have issued a Beach Hazards Statement for now through
Wednesday evening. A long period southerly swell arrives this
afternoon. This long period swell will result in increased risk
of sneaker waves and strong rip currents for south facing
beaches. Strong currents also possible for west facing beaches.
Individuals going to the coast should use caution and are advised
to remain off of exposed coastal rocks and jetties. This situation
will also bring dangerous swimming and surfing conditions along
with the potential of some beach erosion.

&&

.MARINE...as of 09:16 PM PDT Tuesday...Strong northwesterly winds
will continue to generate steep fresh swell around 8 to 10 feet. A
long period southerly swell will  also impact our coastal waters.
Winds and seas will slowly  diminish throughout the week. Locally
breezy conditions will  persist near coastal jets and across the
outer waters, with hazardous conditions for Small Crafts.

&&

.BEACHES...

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm until 3 AM
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm

&&

PUBLIC FORECAST: Bingaman
AVIATION: CW/Behringer
MARINE: CW

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