Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
400 am PDT Sat Apr 25 2015
A low pressure system from the northwest will move inland through
California and Nevada today bringing stronger onshore flow with
strong gusty west winds in the mountains and deserts through this
evening. It will also bring a slight chance of showers today...
mainly near the mountains...with scattered showers this evening
along and west of the mountains...ending late tonight. Warmer and
dry for Sunday. Continued warming for Monday and Tuesday under high
pressure. Surface high pressure over the Great Basin will bring
locally strong gusty northeast winds below the Cajon Pass and
near the coastal foothills of the Santa Ana Mountains late Sunday
night through Monday morning. For Wednesday into next weekend...
cooling will spread inland as onshore flow returns along with night
and morning coastal low clouds and fog.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Short term (today through monday)...
a low pressure system moving inland through California and Nevada
today will maintain stronger onshore flow with periods of strong
gusty west winds in the mountains and deserts...strongest this
afternoon and evening...diminishing late tonight. Winds could gust
to 55 miles per hour...with isolated gusts to 65...mainly in the northern
Coachella Valley below the Banning pass. A few light showers are
possible today...mainly near the mountains. The greatest chances
for showers will be this evening...mainly near the mountains...and
along and west of the mountains in San Diego County. Showers will
diminish from the north overnight. Dry and warmer for Sunday with
continued warming for Monday as surface high pressure over the Great
Basin brings gusty northeast winds below the Cajon Pass and near the
coastal foothills of the Santa Ana Mountains with stronger wind
gusts to around 55 miles per hour.
Long term (tuesday through friday)...
warming will continue into Tuesday with weaker offshore winds.
Cooling will begin near the coast on Wednesday and spread inland
into next weekend as onshore flow returns. Night and morning coastal
low clouds and fog will return and spread farther inland late in the
251000z...coast/valleys...sct clouds 030-050 with areas broken-overcast ceilings
025-040 and tops 060. After 00z...areas of ceilings lowering to 020-030
with scattered rain shower- and west winds increasing 15-20 knots with gust to 25 knots
at times. Winds decreasing 06z-10z sun.
Mts/deserts...coastal slopes and ridges obscured in clouds and occasional
rain shower- increasing in coverage after 00z sun. Westerly winds 15-25 knots
increasing over the ridges and onto the deserts slopes 35 to 40 knots
by late afternoon with local gust 55-60 knots through and below wind
prone passes through Sat night. 22z Sat through 10z sun...areas of
layered clouds with tops to fl120 at times. East of the mountain crests
expect scattered clouds at or above fl080 with strong uddfs and low level wind shear at times. Visible
generally unresrticted...except locally at or below 3sm in bldu in the
230 am PDT...northwest winds will increase to 20 to 25 knots this
afternoon over the coastal waters...with higher gusts over the outer
waters. A large short-period wind swell will develop by evening. The
wind and rough seas will continue through tonight creating a hazard
to small craft. The winds and seas will diminish Sun morning...but
some gusts over 20 knots will continue over the outer waters through
Sun afternoon. A Small Craft Advisory has been issued beginning this
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Wind Advisory from noon today to 10 PM PDT this evening for
Riverside County mountains-San Bernardino County mountains.
Wind Advisory until 10 PM PDT this evening for apple and Lucerne
valleys-Coachella Valley-San Diego County deserts-San Diego
County mountains-San Gorgonio Pass near Banning.
Pz...Small Craft Advisory from 2 PM this afternoon to 10 PM PDT
Sunday for waters from San Mateo Point to the Mexican
border extending 30 to 60 nm out including San Clemente
Small Craft Advisory from 2 PM this afternoon to 5 am PDT Sunday
for coastal waters from San Mateo Point to the Mexican
border and out to 30 nm.