Duarte Weather

000
FXUS66 KLOX 241200
AFDLOX

Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
500 AM PDT Tue Apr 24 2018

.SYNOPSIS...24/253 AM.

A trough of low pressure will approach the West Coast through
Friday before settling over the region through early next week.
This will result in a gradual cooling trend with increasing night
to morning low clouds through Friday. Near normal temperatures
will continue into early next week.

&&

.SHORT TERM (TDY-THU)...24/332 AM.

Latest satellite imagery showed scattered high clouds associated
brushing far southern portions of the forecast area. Closer to the
surface, widespread low clouds and patchy fog were noted across
coastal and some valleys areas including the Salinas Valley
including Paso Robles. Locally dense fog has been observed early
this morning across the Central Coast into the Santa Ynez Valley.
Low clouds and fog will clear to the coast by the afternoon for
most areas. However, a few coastal areas may see low clouds
lingering through much of the afternoon. High temperatures today
will be a few degrees cooler than yesterday for most areas,
except similar for far interior areas such as the Antelope Valley.

Increasing onshore flow and lowering H5 heights ahead of an
approaching trough of low pressure will likely support a gradual
increase in night to morning low clouds Wednesday into Thursday
with low clouds working there way into most coastal valleys by
Thursday morning with fog possible there. The increasing marine
influence will be the main driver for a continued cooling trend,
most pronounced for coastal valleys through Thursday. The
increasing onshore flow will continue to support early onshore
winds, locally gusty across interior foothill areas such as Lake
Palmdale. Model guidance indicates some instability setting up
over the VTA/SBA mountains, Wednesday afternoon and especially
Thursday afternoon. However moisture is too limited at this time
for anything more than afternoon cumulus build ups.

.LONG TERM (FRI-MON)...24/331 AM.

Below average confidence exists in the long term. A trough of low
pressure is poised to push through the region Friday, which will
likely weaken the marine inversion enough to wipe out the low
clouds, at least temporarily to the north of Point Conception.
Advisory level sundowner winds are likely for western portions of
the SBA South Coast Thursday evening, before becoming more
widespread across the region Thursday night into Friday morning.
This may help to limit the extent of low clouds south of Point
Conception, although the downsloping winds may be battling a
formidable eddy. A second piece of upper level energy may help to
reinforce the trough of low pressure overhead by early next week.
This will keep near to below normal temperatures across the region
during this time with gusty winds possible, especially across the
mountains. There is also a non-zero change for rain sometime late
this weekend into early next week, however given the time of year
and inconsistency in model runs, have kept PoPs below mentionable
levels for now.

&&

.AVIATION...24/1159Z.

At 1130Z AT KLAX, the marine layer was near 1200 feet deep. The
top of the inversion was near 1900 feet with a temperature around
19 C.

Moderate confidence in TAFs. Flight Cat transitions may be off by
up to an hour. KOXR and KSBA may not clear at all in the
afternoon.

KLAX...Moderate confidence in TAF. Flight Cat transitions may be
off by up to an hour.

KBUR...Good confidence in TAF. There is a 30 percent chance of
vfr conds Wednesday morning

&&

.MARINE...24/212 AM.

High confidence in winds and seas remaining below Small Craft
Advisory levels across the waters through Wednesday. Winds will
likely increase Thursday through Saturday with widespread advisory
level winds and building short period seas.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

.HAZARD POTENTIAL OUTLOOK (THU-MON).

No significant hazards expected.

&&

$$

PUBLIC...Munroe
AVIATION...Rorke
MARINE...Rorke
SYNOPSIS...Munroe

weather.gov/losangeles

NWS LOX Office Area Forecast Discussion