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

Area Forecast Discussion

National Weather Service North Platte NE

 642 PM CDT Sat May 21 2022

.SHORT TERM...(This evening through Sunday night)
Issued at 230 PM CDT Sat May 21 2022

Frost and freeze conditions are expected late tonight into Sunday
morning. Conditions continue to look favorable for a widespread
frost and a freeze. Surface high pressure will settle down the
Missouri River Valley with very light from the northeast overnight.
Skies will clear and allow for good radiational cooling. Dew points
this afternoon are all below 32F across the forecast area and will
remain in the mid 20 to around 30F overnight. The coldest lows
tonight will be across Sheridan county where some spots could drop
as low as 26F. The rest of the area should see lows of 28-31F where
the Freeze Warning is in effect, and right around 32 or 33 where the
Frost Advisory is in effect. As the center of the surface high
shifts east of the area Sunday, southerly winds will develop and no
further frost or freeze conditions are expected.

The next concern will be strong shortwave energy crossing the
Central and Northern Plains Sunday night though Monday. Mid-level
WAA/isentropic upglide develops Sunday afternoon with an increase in
cloud cover from southwest to northeast across the area. Lift
increases further Sunday evening though Monday morning. The top down
moistening process begins across western Nebraska Sunday evening and
should be fully saturated by midnight when rain should begin. The
rain spreads east into central and north central Nebraska during the
day Monday. QPF amounts are forecasted to be around 0.50" or so
across nearly all of the Sandhills into portions of central and
southwest Nebraska. While amounts are not overly heavy, this will be
a beneficial slow soaking rainfall which the area needs. Instability
continues to look limited or non-existent and will continue to keep
thunder out of the forecast.

.LONG TERM...(Monday through Saturday)
Issued at 230 PM CDT Sat May 21 2022

A rather complicated upper pattern overall into the middle of the
week. Another shortwave moves southeastward through the Rockies and
into the Plains Tuesday and Wednesday. This helps to carve out a
closed circulation at H7 by Tuesday evening across eastern Nebraska.
Most of the rainfall with this second piece of energy is focused
across KS, MO, IA and eastern Nebraska. Some light rainfall cannot
be ruled out across our area and will maintain some low pops during
this period. By the end of the week expect a change. A large ridge
of high pressure will build over the Rockies and then shift east
toward the Plains during the first half of Memorial Day weekend.
Warmer during this time with highs back into the 80s.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 640 PM CDT Sat May 21 2022

VFR conditions expected through the valid period. Vigorous Cu
field with some sprinkles will diminish with loss of diurnal
heating this evening, leaving generally SCT clouds over the
region through tonight. Clouds will begin to surge back into the
area from the southwest Sunday afternoon by any sub-VFR CIGs will
hold off until the next TAF period after 00Z Monday.

Winds may be a bit gusty for an hour or so early this evening,
then become light/variable as good radiational cooling sets in.
Heating on Sunday will mix the boundary layer and generate some
gusts by late in the day but no significant impact to aircraft
operations is expected.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...
Freeze Warning from 10 PM CDT /9 PM MDT/ this evening to 9 AM
CDT /8 AM MDT/ Sunday for NEZ005-024>028-035>038-057>059.

Frost Advisory from 10 PM CDT /9 PM MDT/ this evening to 9 AM
CDT /8 AM MDT/ Sunday for NEZ006>010-029-069>071.

Freeze Warning until 9 AM CDT /8 AM MDT/ Sunday for NEZ004-022-
023-056-094.

&&

$$

SHORT TERM...Taylor
LONG TERM...Taylor
AVIATION...MBS



Area Forecast Discussion

National Weather Service Los Angeles/Oxnard CA

 808 PM PDT Sat May 21 2022

.SYNOPSIS...21/1258 PM.

Warmer temperatures and less marine layer are expected through the
middle of next week as high pressure develops. Night and morning
low clouds are still expected along the coast with some clouds
lingering into the afternoon, especially after Monday. A cooling
trend is expected to begin Thursday with a deepening marine layer.

&&

.SHORT TERM (SAT-TUE)...21/808 PM.

***UPDATE***

Overall, a very quiet evening across the forecast district. Latest
satellite and surface observations indicate some low clouds/fog
across the coastal waters as well as the LAX county coast. Current
AMDAR sounding data indicates marine inversion around 4000 feet
deep south of Point Conception with the inversion likely much
shallower north of Point Conception. As for winds, just the
typical onshore winds lingering with gusts 20-35 MPH in the
foothills.

Forecast-wise for the immediate short term, main issue will be the
extent of the marine layer stratus and fog. With inversion in
place and onshore gradients overnight, stratus should develop and
push well into the coastal valleys south of Point Conception
overnight. North of Point Conception, stratus will mainly be
confined to the coastal plain, but will sneak into the Santa Ynez
Valley. Given the more shallow inversion, there could be some
patchy dense fog overnight north of Point Conception. Other than
any stratus/fog, skies should remain clear overnight. As for
winds, expect the current gusty onshore winds to diminish later
this evening.

Overall, current forecast has good handle on the immediate short
term. Did make some minor tweaks to the sky cover grids, but no
significant updates are anticipated.

***From Previous Discussion***

Deep marine layer still in place south of Pt Conception but skies
are slowly clearing. With much weaker onshore flow today and the
added sunshine in many areas temps are running warmer by 3-6
degrees on average but as much as 10 degrees in some of the
valleys. The eddy has collapsed but low clouds are expected to
return to many of the same areas as last night as well as the
Central Coast.

With a weak upper ridge moving into the state Sunday through
Tuesday and slowly increasing north to northwest flow aloft the
marine layer should clear earlier with warmer temps, especially
inland. Low clouds will become confined to just the coastal zones
by Monday or Tuesday as the marine layer depth lowers to under
1500`. Locally breezy north to northwest winds likely in the far
western part of Santa Barbara County and the I5 corridor but
likely below advisory levels. Then some breezy northeast winds by
Tuesday, mainly in the LA mountains.

.LONG TERM (WED-SAT)...21/106 PM.

The warming trend is expected to peak Wednesday, though there
remains some differences in the models on how strong the upper
ridge will get. Most of the ensembles seem to support the warmer
EC solution but even that solution is fairly moderate in terms of
heat with highs in the mid to high 90s in the Antelope Valley and
near 90 in the coastal valleys, basically about 10 degrees above
normal. Troughing will develop along the west coast Thu/Fri for a
cooling trend with a deepening marine layer and increasing
southerly flow. The GFS continues to advertise an 8-9mb gradient
to BFL late in the week which if true would likely keep low
clouds pretty well socked in along the coast through the
afternoon, especially from Malibu north.

&&

.AVIATION...22/0012Z.

At 2310Z at KLAX, the marine layer was 4800 feet deep. The top of
the inversion was near 6300 feet with a temperature of 13 deg C.

Good confidence in TAFs for KPRB, KPMD and KWJF. Although there is
a 10 percent chance of IFR cigs/vsbys at KPRB between 09-15Z.

Above normal confidence in return to MVFR or lower cigs to
coast/valley TAFs, but below normal confidence in timing (could be
off by 3 hours) and flight category. Near normal confidence in
return to VFR Sunday with return to VFR expected to be within 2
hours of forecast for most terminals.

KLAX...Moderate confidence in the 00z TAF. There is a 30 percent
chance of ceilings returning plus or minus three hours from the
forecasted time. Any east wind component should remain well below
8 kts.

KBUR...Moderate confidence in the 00z TAF. There is a 30 percent
chance of ceilings returning plus or minus two hours from the
forecasted time.

&&

.MARINE...21/807 PM.

The Marine Weather Statement (MWS) for patchy dense fog across
the Outer Waters and Inner Waters north of Point Sal looks good to
continue through tonight.

Marginal Small Craft Advisory (SCA) was allowed to continue for
the Outer Waters north of Point Sal. North to northwest winds are
still expected to increase through Monday. There is a 50 percent
chance of Gales developing across the Outer Waters, especially
north of Point Conception as early as Sunday night and again
Monday. The GALE WATCH remains in place and may be upgraded to
WARNING overnight tonight if model trends continue to support
GALE force wind gusts. SCA conditions are likely (50-70 percent
chance) for the Inner Waters north of Point Sal and western
portions of the Santa Barbara Channel Sunday and Monday
evenings/nights. There is a 20-30 percent chance of at least brief
Gales developing during this time frame.

The strong northerly winds will likely spin up an eddy by Monday
morning, strongest late night to morning with south to southeast
winds possibly peaking between 15 to 20 kts for portions of the
southern Inner Waters, mainly south of Point Mugu.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Sunday for zone
      670. (See LAXMWWLOX).
     Gale Watch in effect from Sunday afternoon through Monday
      evening for zones 670-673. (See LAXMWWLOX).

&&

$$

PUBLIC...MW
AVIATION...Munroe
MARINE...Munroe/Sweet
SYNOPSIS...MW

weather.gov/losangeles

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