San Diego Weather at Mission Trails, CA

323
FXUS66 KSGX 062046
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
Issued by National Weather Service Los Angeles/Oxnard CA
146 PM PDT Tue Oct 6 2026

.SYNOPSIS...
This long-duration heatwave will continue for the coast and
valleys through Thursday and through Friday for the lower deserts.
Cooling will spread inland for Friday and Saturday, but will
remain above normal. For Sunday through early next week, a low
pressure system along the West Coast and off the coast of Baja may
draw moisture from what was Hurricane Rachel northeastward and
into the area with a chance of showers.

&&

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

.SHORT TERM (Today through Friday)...

Today marks day five of the current heatwave. Widespread Major to
Extreme HeatRisk will continue through Wednesday for the coasts
and valleys, as heat stress compounds over time especially given
the warm overnight lows. Today several calender day high records
may be broken (updates on this may be available later this
evening). A small increase in the afternoon sea breeze has
resulted in temperatures a few degrees cooler near to the coast
compared to yesterday. Gradual cooling is anticipated each day
through Friday for coasts and valleys, and HeatRisk will drop to
mostly Moderate to Major for those areas. Expect highs around 12
to 18 degrees above average for the coast and valleys. Across the
low deserts temperatures will increase by a few degrees tomorrow
with highs of 104 to 108 widespread with Major HeatRisk, which is
around 10 to 15 degrees above normal. The Extreme Heat Watch for
the deserts has been upgraded to an Extreme Heat Warning in effect
from 10 AM Wednesday through 8 PM Friday. At this point, Heat
Warnings will probably be allowed to expire Thursday evening for
areas other than the low deserts on Friday, but Heat Advisories
are very possible for Friday.

Surface pressure gradients and thus onshore winds will increase
slightly each day, and by Wednesday or Thursday a shallow marine
layer is likely return, starting with clouds and possibly dense
fog along the coasts. The marine layer will slowly deepen into
the weekend with increased coverage of clouds.


&&

.LONG TERM (Saturday through Tuesday)...
Cooling trends will continue into this weekend with as a fairly
deep trough will likely build down the West Coast. Limited to no
heat impacts are expected for the first time in awhile by this
Sunday with highs generally in the 70s and 80s, hottest towards
the interior.

The National Hurricane Center shows the remnant low from what was
Hurricane Rachel approaching the northern Baja of California this
weekend and will likely pass through this region by early next
week. If the storm tracks closer to the region (40-50 percent
chance), generally light showers within a tropical airmass are
possible Sunday and Monday in particular, focused south and east
of Orange County and across the mountains.

Gusty onshore winds may approach advisory levels for favored
passes mountains and deserts Sunday or Monday.


&&

.AVIATION...
061830Z...SCT to locally BKN clouds based at 8-12 kft inland
through Wed O3Z. Patchy low clouds and fog based around 500-900
feet MSL vcnty KSAN after 03Z into Wednesday morning, but cigs at
KSAN not likely.


&&

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

&&

.BEACHES...
Increasing south swell will create surf of 3-5 feet with sets to 6
feet at south and southwest facing beaches starting Wednesday.
Strong rip currents are expected. In addition, this elevated surf
will combine with high tides during the mornings and evenings to
generate local coastal flooding and beach erosion. The Beach Hazards
Statement and Coastal Flood Advisory contain the details.

&&

.SKYWARN...
Skywarn activation will not be needed today.


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Extreme Heat Warning until 8 PM PDT Thursday for Orange County
     Coastal Areas-Orange County Inland Areas-San Bernardino and
     Riverside County Valleys-The Inland Empire-San Diego County
     Coastal Areas-San Diego County Valleys-Santa Ana Mountains
     and Foothills.

     Beach Hazards Statement from 4 PM PDT this afternoon through
     Friday evening for Orange County Coastal Areas-San Diego
     County Coastal Areas.

     Coastal Flood Advisory from 6 AM Wednesday to 11 AM PDT Friday
     for Orange County Coastal Areas-San Diego County Coastal
     Areas.

     Extreme Heat Watch from Wednesday morning through Friday evening
     for Coachella Valley-San Diego County Deserts-San Gorgonio
     Pass near Banning.

PZ...None.

&&

$$

PUBLIC...RS/RM
AVIATION/MARINE/BEACHES...DB