Alta Loma, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

618
FXUS66 KSGX 070022
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
422 PM PST Fri Mar 6 2026

.SYNOPSIS...
Gusty Santa Ana winds will continue through the weekend across the
mountains into the western valleys as an area of low pressure nears
the region. This will also bring warmer weather with minimal cloud
cover. The system will move southward into Mexico, where there is a
small chance for light rain over San Diego County by late Sunday
into Monday. High pressure will move over the region for much of
next week, bringing warm and dry weather.

&&

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


GOES imagery shows shows an apparent trough of low pressure over
Colorado and Utah today. Behind the trough, northerly flow aloft is
bringing in high clouds over the region, which will continue into
the early evening. Winds out of the north and northeast earlier
this afternoon have been gusting near 25-45 MPH across the valleys
with winds locally over 50 MPH along the coastal slopes. These
winds will become weaker and less widespread this evening and
overnight. The low over eastern Great Basin today will become cut
off by Saturday and move closer to our region. This will allow the
pressure gradient to become stronger once again, leading to
increased winds across the coastal slopes and areas west of the
mountains. Model guidance shows around a 50-70% chance of wind
speeds over 40 MPH by Saturday morning across western portions of
the Inland Empire down into Orange County, along with SD County
coastal slopes. Winds will be higher along the coastal slopes of
SBD/OC counties with moderate to high chances for winds over 55
MPH.

The area of low pressure will move further south on Saturday into
Sunday, which will favor a more easterly wind component around the
northern side of the system. These easterly winds will begin to lead
to stronger winds across San Diego County during this time period.
Highest winds will occur during the morning and afternoon hours each
day. Moderate to high chances exist for foothill regions to reach 40
MPH, while valleys see these chances closer to 25-30 MPH. Offshore
flow will also bring the greatest warming by Sunday. Western valleys
will see moderate to high chances (50-80%) in seeing highs reach 85
degrees. There is about a 50-60% chance to reach 90 degrees across
inland Orange County. These high temperatures would be 15-20 degrees
above normal for early March. The low will wrap around minimal
amounts of moisture with a slight increase in precipitable water
values, which may be able to provide light rain showers from the
deserts to the western valley regions in San Diego County by Sunday
night into Monday. Chances remain low near 15-25 percent with high
confidence in light amounts possible.

Ensemble models show good agreement on the movement of this system,
pushing it out of the area by Tuesday. High pressure off the coast
will move into the area for much of next week. Cooler weather
returns on Monday as offshore winds weaken, but a warming trend
continues through the week as high pressure off the Pacific
strengthens over our region.


&&

.AVIATION...
070000Z....Coast/Valleys...VFR with FEW-SCT high clouds AOA 20,000ft
MSL this evening. After 12z Sat, N/NE gusts to 30-40 kts in the
Inland Empire below mountain passes and 25-35 kts for inland Orange
County periodically through Saturday evening. Weaker offshore winds
(10-20kts) for the coast after 12z; onshore (NW) winds only reaching
areas along the immediate coast, after 18z Sat. Localized areas of
LLWS and mod up/down drafts expected, especially in the lee of
mountains.

Mountains/Deserts...VFR with FEW-SCT high clouds AOA 20,000ft MSL
this afternoon and evening. Gusty N/NE winds expected into Saturday:
25-40 kts with isolated gusts to 55 kts through mountain passes
and on coastal facing foothills. Areas of LLWS and mod up/down
drafts in lee (south of) mountains mainly in SBD County...Brief
lull in strong gusts expected from 02-10z Saturday, but gusts
30-40 kts expected in the mountains/passes during this period. Low
confidence on gusts exceeding 35 kts at KPSP Saturday, most likely
12-16z.

&&

.MARINE...
Intermittent gusts near 20 knots possible in the outer coastal
waters near San Clemente Island early Saturday morning and again
Sunday evening. Otherwise, no additional hazardous marine conditions
are expected through Tuesday.

&&

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


&&

.SGX WATCHES/WARNINGS/ADVISORIES...
CA...Wind Advisory until 5 PM PST Sunday for Orange County Inland
     Areas-San Bernardino County Mountains-San Bernardino and
     Riverside County Valleys-The Inland Empire-Santa Ana
     Mountains and Foothills.

     Wind Advisory from midnight tonight to 5 PM PST Sunday for
     Riverside County Mountains-San Diego County Mountains-San
     Diego County Valleys-San Gorgonio Pass near Banning.

PZ...None.

&&

$$

PUBLIC...APR
AVIATION/MARINE...Westerink