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Area forecast discussion 
National Weather Service San Diego California
217 PM PST Friday Dec 26 2014

Synopsis...
gusty northeast winds are expected to continue at times
along the coastal slopes of the mountains and adjacent foothills
through Saturday morning. Below average temperatures can be
expected as well this weekend with areas of late night through
early morning frost in portions of the valleys and deserts into
Sunday morning. Weaker winds...with continued below average
temperatures Sunday and Monday. For Tuesday through Thursday of next
week a cold...low pressure system could bring periods of
precipitation and gusty winds along with well below average
temperatures.

&&

Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
counties...

Short term...(today through sunday)...
gusty winds will continue into Saturday in some areas as high
pressure at the surface sags south into the plateau. The local
WRF indicates the favored areas in the Santa Ana Mountains and San
Diego County mountains should see some gusts to around 50 miles per hour
during this episode.

The surface high is a cold dry one...so late night through early
morning frost in portions of the valleys and deserts into Sunday
morning can be expected. BUFKIT soundings at the lowest levels looks
similar tomorrow morning in comparison to today. Current thinking
is that the lowest temperatures are expected for Saturday
night...especially in the Lower Desert areas.

&&

Long term...(monday through wednesday)...
cool Monday...then Tuesday through Thursday of next week a cold
low pressure system from the north has the potential to bring
significant impacts to Southern California. It should be noted
that there is much variation between the models...including
timing and placement of the low. We do plan on seeing some
precipitation during this period...however.

The GFS has been leaning toward late Tuesday into Wednesday for
rain. The GFS ensemble mean also supports an indication of rain
possible. On the latest run of the European model (ecmwf)...there may be some more
consistency between the models creeping in...with the late Tuesday
into Wednesday time frame targeted as well.

There is also the potential for low to very low snow levels at
times...below 3000 feet...and periods of strong gusty winds. The
current forecast maintains below average temperatures and mostly
slight chance to chance probability of precipitation for the Tuesday through Thursday
period. The GFS ensemble mean also supports an indication of rain
possible. For now...there will be periods in the Tuesday through
Thursday time frame where temperatures will be quite low...snow
levels lowered...probability of precipitation increased...and winds strengthened.

&&

Aviation...
262130z...sky clear conds with p6sm visible through Saturday afternoon.
Northeast surface winds with local surface gusts 30-40 knots through
Sat morning...mainly in and below the Santa Ana Mountain
canyons...inland Empire...high foothills of the San Diego County
coastal mountains. And NE wind prone areas of the Coachella Valley.
These winds may reach vicinity
ksna...kont...ksbd...kral...kcno...krnm...kpsp...and ktrm with low level wind shear
at times. Strong up/downdrafts are possible in mountain wave
activity on the coastal side of the mountains and near the passes.

&&

Marine...
130 PM...northeast winds over the coastal waters in between
Oceanside and San Clemente and westward to San Clemente Island will
continue to gust to around 20 knots through early . Similar offshore
winds are expected to develop tonight and continue through Saturday
morning. &&

Beaches...
130 PM...a long-period west-northwest will continue elevated surf of
3-5 feet...with local sets to 6 feet...and strong rip currents at
area beaches today. Swell and surf will subside over the weekend.

&&

Fire weather...
gusty northeast winds at times along the coastal mountain slopes and
adjacent foothill areas in Orange and southwestern San Bernardino
counties into Saturday morning...then expand into the coastal
mountain slopes and adjacent valleys in Riverside and San Diego
counties for late tonight through Saturday morning with occasional
gusts to 50 miles per hour. A cool atmosphere will remain in place with lowest
daytime humidities around 15 percent... mainly in portions of the
valleys and inland Orange County.

&&

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

&&

Sgx watches/warnings/advisories...
California...Small Craft Advisory for winds from 10 PM this evening to 7 am
PST Saturday for the San Diego County coastal areas.

Wind Advisory until noon PST Saturday for the Orange County
coastal areas...San Bernardino County mountains...San
Bernardino and Riverside County valleys-the inland Empire...
Santa Ana Mountains and foothills.

Frost advisory until 9 am PST Saturday for the San Bernardino
and Riverside County valleys-the inland Empire...San Diego
County valleys.

Frost advisory from 3 am to 7 am PST Saturday for the San Diego
County deserts.

Frost advisory from midnight Saturday night to 8 am PST Sunday
for the San Diego County deserts.

Frost advisory from midnight Saturday night to 8 am PST Sunday
for the Coachella Valley.

Frost advisory from midnight tonight to 8 am PST Saturday for
the San Diego County coastal areas.

Wind Advisory from 4 am to noon PST Saturday for the San Diego
County mountains...San Diego County valleys.

Pz...Small Craft Advisory for winds from 10 PM this evening to 7 am
PST Saturday for the coastal waters from San Mateo Point to
the Mexican border and out 30 nm...waters from San Mateo
Point to the Mexican border extending 30 to 60 nm out
including San Clemente Island.

&&

$$

Public/fire weather...small
aviation/marine...jt

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