Norco, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

249
FXUS66 KSGX 142020
AFDSGX

Area Forecast Discussion
National Weather Service San Diego CA
120 PM PDT Mon Apr 14 2025

.SYNOPSIS...
A trough of low pressure will keep us cool and breezy this week.
Cooler weather will take hold by Wednesday through Friday as a
deep marine layer impacts the foothills to the coast where morning
drizzle can be expected over the next couple of days. The area of
low pressure will become stronger and push ashore by Wednesday
through Friday, leading to much cooler and windier weather for
inland areas. We may also see a chance of rain by Thursday and
Friday as well. After this passes, warmer and drier weather will
move in around next weekend.

&&

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

Low clouds have cleared nicely off the coastline. High clouds
continue to push in from the south a trough maintains its hold
over the area. Look for better clearing from south to north as we
continue throughout the day. The marine layer will become slightly
deeper into tonight with most low clouds filling back into the
coastal basin. Spotty drizzle will also make an appearance areas
west of the mountains as well by Tuesday morning. A stronger area
of low pressure will begin to form off the coast during this time.
This feature will stick around through the work week, bringing
cooler and breezier to the region. Highs by Tuesday will sink a
few degrees cooler than where they are today.

As the low deepens and moves closer to our area on Wednesday and
Thursday, cooler and breezier weather will take hold. High
temperatures will go down another 5 degrees or so for inland
areas. West winds will increase across the mountains and deserts.
In terms of wind speeds, probabilities significantly change from
between 30 and 45 mph wind thresholds, elevated winds are looking
more likely to occur. Thursday will be the coolest day over all
across the region with highs in the 60s west of the mountains into
the high desert. Some mountain areas near Big Bear will stay in
the 40s while the lower deserts stay near 80 degrees or less.
Though the exact track of this low is still uncertain, a chance of
showers is in the forecast as model ensembles show light amounts
of precipitation expected later on Thursday into Friday.
Confidence is low on exact amounts, but not looking like anything
substantial. We will also have to monitor the chance for
thunderstorms during this time period as well, though current
guidance does not show a strong signal of this occurring.

Another area of low pressure is expected to drop in from the north
by later in the week as well. Depending on the exact track of this
system will see how long the cooler, breezier, and showery weather
sticks around. The latest NBM output shows greater warming and
less wind, aligning with ensemble models showing neutral by the
weekend.

&&

.AVIATION...
142000Z....Coasts/Valleys...Satellite shows that the low clouds have
cleared completely while SCT-BKN high clouds based above 20,000ft
prevail nearly region-wide. Slightly higher based low clouds will
redevelop this evening and push inland after 03z. The coastal basin
should fill in completely before 12z Tuesday morning, with -DZ
possible for coastal and valley areas. Clearing of these low clouds
and DZ will occur at a similar time as this morning, around 16-19z.

.Mountains/Deserts...Prevailing SCT-BKN clouds based 20,000ft MSL
through Tuesday. Periods of gusty winds this evening and tonight
between 02z-12z Tuesday in the mountain and Coachella Valley.

&&

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

&&

.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...APR
AVIATION/MARINE...Zuber