National Weather Service Forecast Discussion

Dicussion provided by the National Weather Service Forecast Office located in San Diego, California

000
FXUS66 KSGX 152016
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
116 PM PDT Sat Jun 15 2019

.SYNOPSIS...
Weak low pressure aloft will maintain typical June weather with
near to slightly below normal daytime temperatures and marine
clouds and fog spreading well inland each night. Midday clearing
back to coastal areas is expected, but clearing may be delayed or
limited some days due to fluctuations in the marine layer and cloud
depth. The deserts will be seasonably hot under fair skies. Slight
warming is possible mid next week as a ridge attempts to build
aloft, but a return to cooler weather is likely before the
weekend.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

Marine stratus had mostly cleared the coast at 1 PM PDT, however
some broken areas of low clouds remained over the immediate coastal
areas. The sfc pressure gradients remained onshore but were weaker
than yesterday and winds were lighter as well. Expect the marine
layer to spread rapidly back inland this evening and again extend
well into the valleys by morning, although not as deep as this
morning.

A series of weak troughs will maintain low pressure aloft over SoCal
through early next week, supporting the marine layer and holding
daytime temperatures a bit below average. Marine stratus will
continue to surge well inland each night, but should clear back to
coastal areas each day. No guarantee on any given day or time for
sun at the beaches as onshore flow prevails, but expect at least
partial clearing most days.

A strong ridge will redevelop over the far EastPac, west of KSFO
next week. The ridge will nose eastward across CA midweek and may
flatten the marine layer and bring some warming, especially inland
about Wednesday before it weakens. Hard to say whether it will last
long though as another trough in the Westerlies to the north digs SE
across the northern Rockies. The ECMWF solutions have been most
aggressive with this feature, turning it into a full, longwave
trough over the West by Saturday. The GFS ensemble mean generally
agrees, although the operational run is much weaker. With that in
mind, expect more relatively cool weather next weekend. The temp
grids have been blended to bias them cooler in the extended period
since this looks to be consensus.

&&

.AVIATION...
152010Z...Coast/Valleys...Other than some SCT-BKN 2000 ft MSL cigs
at the coast, most areas will be mostly clear for the afternoon.
Stratus will move back into the coastal areas after 16/02Z with
bases 1500-2000 ft MSL, spreading 25-30 mi inland overnight with
slightly lower bases. Sites near KONT/KSBD 2-4 sm in HZ/BR late
evening into early morning possible.

Mountains/Deserts...Mostly clear with unrestricted vis through
Sunday. West winds with sfc gusts 25-35 kt will occur along the
mountain crests and desert mountain slopes and below the passes this
afternoon and evening, weakening tonight. Strong up/down drafts are
possible over and east of the mountains.

&&

.MARINE...
No hazardous marine conditions are expected through Thursday.


&&

.SKYWARN...
Skywarn activation is not requested. However weather spotters are
 encouraged to report significant weather conditions.


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&

$$

PUBLIC...10
AVIATION/MARINE...APR

NWS SGX Office Area Forecast Discussion