Dana Point, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

385
FXUS66 KSGX 010938
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
238 AM PDT Sun Jun 1 2025

.SYNOPSIS...
An area of low pressure to the south will bring a chance for
showers and thunderstorms today and tomorrow. Cooler temperatures
with values near normal will occur through much of the upcoming
week. By Tuesday, quieter weather with drier conditions will
continue into the following weekend.

&&

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

Today through tomorrow...

Southerly flow overnight as allowed for increased moisture and
humidity values, as well as relatively milder temperatures. Because
of this, there could be some locations this morning and tonight,
which may tie or break daily maximum low temperature records.

Currently, there is high pressure conditions occurring near the
surface with patchy low clouds and fog for some locations along the
coast this morning, however, a cut-off upper level low which has
tapped into tropical moisture from Alvin from the south, that is
influencing the region with weak to moderate instability aloft in
the mid to upper levels. It will be conditionally unstable enough,
with the HRRR showing values of MUCAPE increasing to over 1000
J/kg for some of the mountainous areas by later this afternoon,
which will likely lead to the development of a few thunderstorms,
especially over the mountains and east-facing slopes of the
deserts in San Diego County. This is in part due to the
southeasterly flow around the U/L low, which will be increasing in
the mid levels throughout the day and orographic lifting. This
will help to induce convection with upsloping, with areas such as
Jacumba and Boulevard (or within the vicinity) likely getting some
decent rainfall amounts; possibly exceeding a half an inch by
later this afternoon with daytime heating allowing for the
development of heavier showers and storms possible over these
locations. These areas will have a higher probability of seeing
storms today, of 50 to 70 percent, and then this tapers off to
around a 20 percent probability going north and west to the
coastal areas of San Diego and Orange counties. Other areas, such
as the San Bernardino Mountains, will also have a better chance of
receiving higher rainfall amounts of possibly a half an inch or
locally greater. The deserts will also have a better chance of
receiving precip, given the set up and orientation of mid-level
flow coming out of the SE. It will be notably cooler today, given
the lower heights and extensive cloud coverage, and much closer to
the seasonal average for this time of year.

Models have been tightening up with the progression of this U/L low
is it continues to propagate towards the northeast by later in the
day. The position of the low by later in the day will not be as
favorable for San Diego proper, given that it will be located
underneath the convergent quadrant of the U/L low. Despite this,
there could be enough of a push as winds at the 700 mb level will be
jamming at roughly 20 to 30 kts out of the east-southeast, which may
allow for some of these storms forming over the mountains to push
off, at least move over into the inland areas, but also could
impact some of the coastal areas with storms by later in the day.
This is all depended in where the embedded waves and areas of PVA
will be positioned around the U/L low at the time that it begins
to transition NE`ward as it is "kicked" by another U/L low moving
down from central California as the trough further deepens. This
secondary U/L low could also help to play a role in keeping the
chance of precip going into tomorrow, with the threat of storms
developing again over the mountains tomorrow afternoon.

Tuesday through next weekend...

The general consensus of ensemble members and deterministic models
alike keep the longwave trough in place over the western states,
with only some weak ridging building back in towards the end of the
week, which will allow for a gradual warmup. For Tuesday and
Wednesday, there could be just enough instability from the secondary
U/L low nearby to allow for an isolated shower or storm to develop
during the afternoon over the mountains, otherwise, with will be
mostly clear with high pressure conditions in place. The marine
layer will likely be more displaced for the next couple of days, due
to the U/L disturbance overhead, although it should become more well
defined and persistent for the coastal areas by later in the week as
onshore flow becomes more predominant. Temperatures will remain near
the seasonal average going into next weekend.

&&

.AVIATION...
010915Z...Coasts/Valleys...Patches of virga are moving over the
region from east to west tonight, but aren`t providing much impact
to any terminals other than few sprinkles reaching the ground at
times. Meanwhile, patchy low stratus is present offshore which could
occasionally push ashore and bring CIGs to the coastal TAF sites.
There is a 20-40% chance of low CIGs for KSAN/KCRQ/KSNA through
about 14Z. Cloud bases expected to be 500-900ft MSL with VIS 2-5 SM
along the coasts and 0-3 SM for coastal mesas. Any low clouds/CIGs
will clear back out by 15Z, with prevailing SCT-BKN high clouds 10-
15k ft MSL through today. Iso TSRA are possible for the far eastern
valleys and foothills, primarily after 18Z today, along with a
slight chance for SHRA through the region. SHRA/TSRA chances
diminish after 02Z Mon, and more uniform low clouds will move 15-20
miles inland after 06Z Mon, based 800-1200 ft MSL.

Deserts/Mountains...SCT-BKN high clouds at 10,000-20,000 ft MSL
prevail today. Iso-Sct TSRA possible after 18Z today with the
greatest coverage over the mountains. Brief outflow gusts over 25-
30kts possible with any developing SHRA or TSRA. Near zero VIS
possible in any storm with heavy rain, along with erratic and gusty
winds. TSRA chances diminish after 03Z Mon, with lingering showers
tapering off by 10Z Mon.

&&

.MARINE...
Chance of showers (20-35%) today across the coastal waters, with a
low chance for thunderstorms around 5% this afternoon. Otherwise, no
additional hazardous marine conditions are expected through
Thursday.

&&

.BEACHES...
A long period south swell will build into the region today, leading
to elevated surf for south and southwest facing beaches of 4 to 6
feet with sets to 7 or 8 feet possible. This will result in higher
rip current risk and locally hazardous swimming conditions. Surf
peaks Monday and gradually diminishes Tuesday through Wednesday. A
Beach Hazard Statement is in effect and contains more information.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Beach Hazards Statement from 9 AM PDT this morning through
     Tuesday afternoon for Orange County Coastal Areas-San Diego
     County Coastal Areas.

PZ...None.

&&

$$

PUBLIC...Stewey
AVIATION/MARINE/BEACHES...CSP