Anza, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

477
FXUS66 KSGX 121538
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
838 AM PDT Sat Apr 12 2025

.SYNOPSIS...
Subtle cooling this weekend followed by more significant cooling
for the second half of next week. Low clouds and fog will
continue across the coastal areas and western valleys each morning
through the middle of next week. There is a 15% chance of light
precipitation over the mountains Monday night, and then a 10-20%
chance for the mountains westward at times Thursday night through
Saturday.

&&

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

.UPDATE...
Low clouds and fog remain across coastal San Diego and Orange
counties, up to 15 miles inland. Visibility is currently around 1-2
miles for coastal mesas and 3+ miles elsewhere. Clouds will be slow
to clear today, likely retreating to the beaches by 11 am or 12 pm
where they will linger through the afternoon. Otherwise, generally
sunny skies and moderately gusty west winds in the mountains and
deserts today, with up to 25-35 mph in the deserts and up to 40-45
mph in the mountains and mountain passes. Above normal
temperatures continue today but will slowly be falling through
Sunday and into next week, becoming below normal for areas west of
the mountains by Tuesday. Another round of low clouds/patchy fog
expected Sunday morning, and for most mornings through next week,
with limited visibility impacts.


.PREVIOUS DISCUSSION FROM 251 AM...
The marine layer has deepens significantly this morning as the
upper ridge continues to shift east and a weak coastal eddy
prevails, with low clouds extending into portions of the San Diego
County valleys. Any dense fog will be sparse and limited to areas
where clouds move into higher terrain in the valleys. Otherwise
there were scattered high clouds, including some standing wave
clouds downwind of the peninsular range. Low clouds will clear to
the coast by late morning, with scattered high clouds and wave
clouds continuing into this evening.

A cooling trend begins this weekend as the upper level ridge
continues to move eastward and weaken. An upper level trough
moving towards the West Coast tonight becomes split, with the
northern branch moving into Central CA and stalling while the
southern branch digs southward and closes off well off the coast
of Central Baja. Night and morning low clouds and patchy fog will
continue across the coastal areas and far western valleys. Some
weak ridging tries to nudge in from the east on Monday for minor
warming and a slight decrease in the marine layer depth, though
not enough for dense fog to be a concern.

The upper low off the coast of Baja becomes a negatively tilted
open wave as it moves into the Southwest US Monday night. Moisture
with this wave is extremely limited and high based (above 700 mb).
EPS has several members with light precipitation over the
mountains, but far less for the lower elevations, with the GEFS
even drier, unlike its deterministic counterpart. Added a slight
(15-20%) chance over the mountains Monday night, though any
accumulation will be limited to a few hundredths if that.

As that wave moves through, another low digs south through the
mean trough and closes off in a similar position to the first one.
There is still considerable spread in the timing of this low
lifting northeast into So Cal sometime Wed/Thu, as well as the
evolution of another trough in the northern stream of the jet,
which may develop into a large closed low and drop south into CA.
While each of the 00Z deterministic models show this scenario,
which would result in much colder and wetter weather, it is only
supported by 34% of the ensemble space. The alternate scenario is
for this trough to move across the Northern Rockies with the
southern tier closed low lingering to our southwest or over us for
less cooling and lower precipitation chances. Slight (15-20%) chances
of precipitation have been added for the mountains and parts of
the valleys Thursday night through Saturday. Based on these wildly
different solutions there is low confidence in snow levels and
precipitation amounts.

&&

.AVIATION...
121530Z...Coasts and western valleys...Low clouds/FG extending
from the coastal waters to the western valleys about 10-15 miles
inland. Bases currently around 500-700 feet MSL may continue to
slowly rise through the morning. Visibility 3-5 SM at coastal
sites will continue to slowly improve with lower vis remaining
confined to higher coastal terrain and western valleys. Low clouds
retreat to beaches 16-18Z, but again will linger along the
immediate coast through the day.

Low clouds return to the coasts and western valleys after 01Z Sun,
with higher bases above 800 ft MSL. FG where clouds intersect
terrain. 60% chance of low clouds/FG pushing into the western inland
empire locations such as KONT.

Elsewhere...Mostly clear skies through Saturday night with VFR
conditions. West gusts 25-35 kt over the mountains into the passes
and deserts Sat afternoon and early evening.

&&

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

&&

.BEACHES...
Surf 3-6 feet, with local sets to 7 feet on southwest facing
beaches, are expected through Sunday morning, bringing a high risk
for rip currents.

&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement through this evening for Orange County
     Coastal Areas.

PZ...None.

&&

$$

PUBLIC...Zuber
AVIATION/MARINE/BEACHES...Small