Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 05/23/22

Area Forecast Discussion

National Weather Service Los Angeles/Oxnard CA

 732 PM PDT Sun May 22 2022

.SYNOPSIS...22/514 PM.

Warmer conditions expected through at least the middle of the
week under developing high pressure. The marine layer will
continue to impact coastal areas, but will be less expansive that
it was at the end of last week. Gusty winds will affect the
mountains and interior valleys each afternoon and evening.

&&

.SHORT TERM (SUN-WED)...22/731 PM.

***UPDATE***

Overall, another quiet evening across the forecast district.
Latest satellite and surface observations indicate mostly clear
skies for most areas with some stratus over the coastal waters and
along the beaches. Current AMDAR sounding data indicates marine
inversion around 1000 feet deep. As for winds, typical
southwesterly onshore winds continue across interior sections with
some weak northerly winds across the SBA South Coast. All winds
are well below any advisory concerns.

For the immediate short term, main issue will be the marine layer
stratus and fog. Overnight, H5 heights increase a bit which should
prevent any appreciable deepening of the inversion. However, high
resolution models indicate an eddy circulation over the Bight
which should result in widespread stratus/fog across the coastal
plain south of Point Conception, but only limited penetration into
the coastal valleys (due to the shallow nature of the inversion).
North of Point Conception, will anticipate some stratus/fog
overnight around the Lompoc/Vandenberg area, but mostly clear
skies elsewhere.

Overall, current forecast has good handle on the immediate short
term. Other than some minor tweaks to the areal coverage of the
marine layer stratus/fog, no forecast updates are anticipated.

***From Previous Discussion***

Marine layer clouds from last night have lingered over portions
of the waters today, and will have the tendency to push into a
few coastal spots this afternoon. Otherwise, expecting a nice
sunny day with temperatures within 5-10 degrees of normal.

By tonight, pressure gradients favor northerly flow supported by
a LAX-BFL offshore pressure gradient of around 3 mb. Some breezy
conditions are expected for the southern mountains, the I-5
cooridor, Antelope Valley, and along western portions of the
Santa Barbara South Coast. Northerly winds will remain below
advisory levels (gusts up to 35 mph, isolated gusts 40 mph near
Gaviota expected). An early return of marine layer clouds is
possible for the LA Coast, and cloud and fog should favor southern
portions of the region due to a Catalina Eddy.

Heights continue to rise through Monday, further squishing the
marine layer and driving the warming trend. Northerly gradients
are stronger Monday night, but winds are still expected to remain
below advisory levels.

.LONG TERM (THU-SUN)...22/109 PM.

Ensembles appear in good agreement with the current pattern,
transitioning from ridging to troughing over the Wednesday to
Saturday timeframe. Warming is forecast to peak Wednesday, with
the ridge centered on the region. Currently, guidance suggests
temperatures 10-15 degrees above normal for interior areas, with
much cooler near normal values at the coasts due to good westerly
onshore flow. Expecting more evening to morning marine layer
clouds at the coasts through Friday morning. Westerly onshore flow
peaks Thursday as temperatures start to fall off and heights
lower, allowing for a deeper marine layer and clouds to push
towards the valleys Thursday night. Things change late Friday as
an upper level trough brings in NW flow, scouring out marine
layer clouds. Saturday appears similar, with little change to the
overall pattern.

&&

.AVIATION...23/0028Z.

At 23Z at KLAX, the marine layer was 1100 feet deep. The inversion
top as at 3300 feet and 18 degrees Celsius.

Chances of LIFR conditions tonight, 40 percent chance at KBUR, 20
percent chance at KSMX KSBA KOXR KCMA. Chances of IFR conditions
tonight at KSBA (70%) KOXR (90%) KCMA (60%) KSMO (80%) KLAX (80%)
KLGB (80%). High confidence in VFR at KPRB KSBP KWJF KPMD. High
confidence in gusty onshore winds typical for this time of the
year.

KLAX...High confidence in low clouds tonight, with BKN010-012
starting 01-04Z, then lowering to OVC007-010 by 03-08Z. Chance of
LIFR conditions less than 10 percent. Moderate confidence in and
east winds staying well under 8 knots.

KBUR...High confidence in VFR through at least 06Z. 40 percent
chance of low clouds and fog starting 08-11Z and lasting 14-16Z.
If they form will likely be LIFR OVC003, with a chance of VLIFR
dense fog VV001.

&&

.MARINE...22/643 PM.

High confidence in Gale Force winds affecting the outer waters
north of Point Sal through Monday Night, except for a brief break
Monday morning. Converted the Gale Watch to a Gale Warning as a
result. Moderate confidence that those Gale winds will also extend
to the outer waters northwest of San Miguel Island, but high
confidence they will stay at least 30 miles from the nearest shore
(northwest portion of zone PZZ670). These winds will also create
Small Craft Advisory conditions for the nearshore waters of the
Central Coast and outer waters down to San Nicolas Island, for
winds 20-30 knots and/or choppy seas. The rest of the area should
have fairly benign and seasonal conditions, with Southeast morning
winds 5-10 knots, and typical seabreezes.

For Wednesday through Thursday afternoon, southerly winds will
push up to Monterey County and shove the seasonal coastal jet well
offshore. Local south to southeast winds of 10-15 knots are likely
near all coasts in the morning hours, especially Wednesday. More
significantly, seas will fall to nearly lake-like conditions by
Thursday, with only 2-4 feet total waves everywhere including the
Central Coast. The coastal jet should reform quickly Thursday
Night into Friday, with Gale Force winds and widespread choppy
seas returning for the weekend.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect from 1 PM to 9 PM PDT Monday
      for zone 645. (See LAXMWWLOX).
     Gale Warning in effect until 3 AM PDT Tuesday for zone 670. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 PM PDT Monday for zone
      673. (See LAXMWWLOX).
     Gale Warning in effect from 3 PM Monday to 3 AM PDT Tuesday
      for zone 673. (See LAXMWWLOX).
     Small Craft Advisory in effect until 3 AM PDT Tuesday for
      zone 676. (See LAXMWWLOX).

&&

$$

PUBLIC...Phillips/Thompson
AVIATION...Kittell
MARINE...Kittell
SYNOPSIS...RK

weather.gov/losangeles

Experimental Graphical Hazardous Weather Outlook at:
https://www.weather.gov/erh/ghwo?wfo=lox