Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
330 am PST Sat Nov 22 2014
a low pressure system moving inland through northern California and
the Great Basin will bring gusty west winds to the mountains and
deserts this afternoon and evening. Surface high pressure over the
Great Basin will bring stronger Santa Ana winds for Sunday afternoon
into Monday with the Santa Ana winds slowly decreasing through
Thursday. High pressure aloft near the West Coast will bring warming
for Monday through Wednesday. Onshore flow is expected to return
late in the week bringing cooling.
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 northern California will
bring stronger onshore flow with gusty west winds for the mountains
and deserts this afternoon through early Sunday morning. Satellite
imagery and surface reports have shown patchy stratus the past few
hours over far northwest Orange County and far southern Los Angeles
County. Patchy stratus is possible near the coast early this
morning...but weak offshore drainage flow should keep it fairly
limited. A greater return of stratus and deepening of the marine
layer to 3500 to 4000 feet tonight through early Sunday is expected.
Flow will transition to offshore Sunday with moderate strength
offshore flow continuing into Monday. This could bring advisory
strength offshore winds for the coastal mountain slopes and adjacent
foothill areas for late Sunday into Monday. High temperatures will
warm west of the mountains for Sunday and Monday while they cool in
Long term (tuesday through friday)...
high pressure aloft along the California coast will peak
Tuesday...then weaken Wednesday and Thanksgiving. Toward the end of
the week...a low pressure system may move inland through California
with continuing model differences in the timing and strength.
High temperatures will peak Wednesday...then slowly cool into next
weekend. Gusty Santa winds will continue for Tuesday...then slowly
weaken for Wednesday and Thursday.
221050z...coasts/valleys...few-sct clouds at or above 20000 feet mean sea level and
unrestricted visible through this evening. Patchy stratus with bases
1500 to 1800 feet mean sea level and tops to 2500 feet mean sea level forming west of the mountains
after 23/03z...clearing early Sun morning as offshore flow develops.
Areas of NE surface winds gusting 35-50 knots developing below the Cajon
Pass and Santa Ana Mountains after 23/12z with associated low level wind shear vicinity kont
Mountains/deserts...west winds with surface gusts 30-40 knots after 21z in
the High Desert...and over/east of the mountain ridges and adjacent desert
slopes and foothills. Low level wind shear and strong uddfs possible along and east of the
mountains west winds diminishing after 23/06z. Local gusty north-NE winds and
low level wind shear possible over portions of the northern Coachella Valley Sun
morning...including vicinity kpsp. Blowing dust may reduce visible at times
in the deserts through Sun morning. Otherwise few-scattered clouds at or above
20000 feet mean sea level and unrestricted visible.
310 am...west to northwest winds gusting to around 20 knots possible
this evening through Sunday morning over the outer coastal waters as
a low pressure trough moves across the region. Otherwise no
hazardous marine weather is expected Sunday afternoon through
dry offshore flow will develop Sunday with gusty northeast winds
surfacing in the mountains and through the passes and canyons into
the inland valleys. The strongest winds will initially surface from
Cajon Summit through the Cajon Pass and into the inland Empire and
Orange County late Sunday morning. Winds in these areas will range
from 20 to 30 miles per hour with peak gusts to 45 miles per hour. Winds will spread
southward into Riverside and San Diego counties Sunday afternoon and
night. Moderate strength northeast winds will continue into
Monday...then slowly weaken for Tuesday through Thursday.
Lowest inland humidities will fall to 10 to 15 percent Sunday
afternoon. For Monday through Wednesday...lowest daytime inland
humidities of 5 to 10 percent with poor overnight recovery. Recent
rainfall has briefly increased fuel moisture which will reduce the
fire weather potential Sunday. Red flag conditions are possible for
Monday and Tuesday.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Wind Advisory from 6 PM this evening to 3 am PST Sunday for the
Coachella Valley...Riverside County mountains...San Diego
County deserts...San Diego County mountains.
Wind Advisory from 1 PM this afternoon to 3 am PST Sunday for
the apple and Lucerne valleys...San Bernardino County