894 
FXUS66 KLOX 121824
AFDLOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 
1124 AM PDT Sun Mar 12 2017

.SYNOPSIS...
High pressure aloft and weak offshore flow at the surface will 
persist through Monday. Near record heat is forecast for areas 
away from the coast through Monday. A slight cool-down is expected
Tuesday through Thursday.

&&

.SHORT TERM...(TDY-TUE)

Main story this morning is the amount of dense fog stretching from
the Santa Barbara area all the way to Orange County. Satellite
reveals that there is rapid retreat to the beaches occurring
across Los Angeles County and not so much elsewhere. High
resolution model data shows surface temperatures will be impacted
so have lowered maximum temperatures for the Oxnard Plain and LA
Basin including downtown. Will keep it under 80 degrees at CQT and
about 70 for OXR today. Pressure gradients are weakly onshore and
expect the northeast winds to be weak and confined to interior
valleys and mountains today. None the less, it will be a warm day
for interior valleys with highs into the lower 90s. Next question
is the amount of low clouds and dense fog coverage tonight.
Everything points toward a repeat performance of dense fog south
of Pt Conception and even more coverage along the Santa Barbara
Coast as a small eddy spins up early Monday morning. Will work on
this scenario and adjust temperatures accordingly for the next
forecast package.

.LONG TERM...(WED-SAT)

Ridging aloft will remain in place through at least Friday. 500 mb
heights climb for late week and temperatures should bump up for 
Friday to near record levels again. Both medium range models and 
model trends point toward cooling for next weekend and into early 
next week. GFS model trends suggest a deepening broader trough 
circulation along the West Coast. Confidence is growing for a
cooler weather pattern for next weekend and into early next week
along with developing marine layer induced stratus.

&&

.AVIATION...12/1800z.

At 1731Z at KLAX...The marine inversion was 700 feet deep.  The 
top of the inversion was around 2200 feet with a temperature of 
about 22 degrees Celsius.

Overall...Moderate confidence in the coastal TAFs south of Point 
Conception and moderate to high confidence in the other TAFs. 
Dense fog was hanging on the beaches and no longer affecting the
coastal TAF sites, but seems rather likely to return to the same
areas again tonight, namely the coastal TAF sites south of Point
Conception. However, the KSBA TAF only has a 40 percent chance of
fog tonight.

KLAX...Moderate confidence in the current TAF. Dense fog is
expected to return overnight tonight with another round of dense
visibility and LIFR ceilings. 

KBUR... Moderate to high confidence in current TAF. VFR 
conditions will prevail throughout the forecast period.

&&

.MARINE...12/900 AM...

Small Craft Advisory (SCA) conditions will continue across the
outer waters through late Monday. 

Conditions across the inner waters south of Point Conception will
remain below SCA levels through the middle of next week though
with local gusts to 25 knots across the western Santa Barbara 
Channel.

Local dense fog will continue through the day for the inner 
waters south of Point Conception as well as the southern outer 
waters.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...Small Craft Advisory in effect until 3 AM PDT Tuesday for
      zones 670-673-676. (See LAXMWWLOX).

&&

.HAZARD POTENTIAL OUTLOOK...(TUE-SAT)
On Friday, near record heat is possible.

&&

$$

PUBLIC.../Hall
AVIATION...Sweet
MARINE...Sweet
SYNOPSIS...jld

weather.gov/losangeles