Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service San Diego California
433 am PST Friday Jan 30 2015

Quick update...
have added fog to the forecast for mountain areas through tonight
due to overcast low to middle cloud decks persisting and possibly
impacting the travel corridors.

&&

Synopsis...
a slow-moving trough will bring light rain and high elevation snow
through this evening. Decreasing showers Saturday. Next week will
be dry and warm with high pressure aloft and weak to moderate
offshore flow.

&&

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

Light rain is falling across our eastern County Warning Area early this morning in
moisture plume originating from the tropics and coincident with
the broad upper level trough. A stalled out surface boundary and
wave is located from Los Angeles south over the coastal waters
where another batch of light rain is ongoing early this morning.
Snow levels are hovering around 6500 feet in the north and
around 7000 feet in the south and near the coast...according to
dual pol Doppler and surface observations.

Weak forcing and widespread anomalously high moisture (00z San
Diego sounding showed a precipitable water of nearly 1") will contribute to
widespread mainly light rain through much of today with the best
focus over the mountains and...believe it or not the southern
deserts and the Coachella Valley. Some enhanced precipitation
should be expected over the mountains and the eastern slopes of
the mountains where orographics will enhance amounts through this
evening at times. No significant changes to our quantitative precipitation forecast which
indicates generally 1/10 to 1/4 inch west of the mountains...1/2
to 1 inch over the mountains and eastern slopes...and 1/10 to 1/4
inch over the deserts. Snow levels will continue to hold through
the precipitation event from 6500 in the north to near 7000 feet
in the south and near the coast. Snow amounts above 7500 feet will
be 2 to 4 inches with the tops of the peaks seeing up to 6 inches.

On Saturday the upper low will exit our region to the
southeast...heading over northern central Mexico on Sunday. A
broad and strengthening upper high pressure ridge over the
eastern Pacific Ocean and into central California will then begin
to take ahold of our regions weather...continuing through middle next
week. This will spell a warmer and drier than normal pattern for
Southern California through at least middle next week. Some
suggestions in the medium range models of a wet pattern setting
up shop for late next week across norcal...but our region would
likely stay south of the Pacific moisture plume if it does
materialize.

&&

Aviation...
301000z...clouds above 7000 feet mean sea level will continue today through
tonight with scattered showers. Some higher terrain will be obscured
at times in clouds and fog. After 00z bases will lower to about 5000
feet mean sea level. At times there will be areas of lower clouds to 2000 feet
and visible 4-6sm along with greater mountain obscuration through
tonight.

&&

Marine...
200 am....no hazardous marine weather is expected through Tuesday.



&&

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



&&

Sgx watches/warnings/advisories...
California...none.
Pz...none.

&&

$$

Public...Brotherton
aviation/marine...mm

National Weather Service Glossary of Abbreviations