Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
925 am PDT sun Mar 16 2014
high pressure aloft over Southern California combined with surface
high pressure over the plateau will bring northeast winds below
canyons and passes through this afternoon...with high temperatures
well above normal. The winds should weaken this afternoon. A trough
of low pressure moving into the Pacific northwest Monday will bring
increasing onshore low level flow and patches of coastal low clouds
Monday morning...with more widespread coastal low clouds by Tuesday
morning. Some gusty west winds are expected with the trough. Weaker
onshore flow will develop Wednesday through the rest of the week
with afternoon high temperatures slightly above average.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Short term (today through tuesday)...
looks like another warm one again today as the surface offshore flow
pattern continues. We are expecting a number of 90 degree readings
west of the mountains again. This is supported by the rather warm
airmass just off the surface just above a shallow...surface based
inversion. This will make for a rapid rise in the temperatures this
morning. NAM BUFKIT soundings show a fully mixed boundary layer this
afternoon to mix down the heat.
Still some good gradients in place. So far 2 mountain sites reached
45 miles per hour wind gusts in San Diego County. The local WRF may be a bit
overdone on the surface winds speeds...but will continue to run with
the Wind Advisory this morning.
Our temporary Summer is over on Tuesday as an upper level trough
dives into the western states. This should reverse the flow
beginning Monday morning with maybe a patch or 2 of low clouds or
fog. By Tuesday the main event begins with the marine layer low
clouds and associated cooling pushing into the valleys early Tuesday
morning. BUFKIT soundings shows substantial low level moisture early
Tuesday as well.
Long term (wednesday through saturday)...
European model (ecmwf) ensemble data shows a fairly Flat Ridge into the early part of
next weekend...then as a low develops in the eastern Pacific it
tries to pump up a ridge over Southern California. The bottom line
indicates that if there is no drizzle out of the Tuesday trough...
dry weather should continue for the next week. Temperatures should
be near to slightly above average.
161530z...clear with unrestricted visible through Monday morning. Patchy
fog with visible 2-4 sm is possible along the immediate coast between
17/11-16z...in the vicinity of ksan...kcrq and ksna...though confidence
is relatively low of actual impact to the airports themselves.
a long-period northwest swell will build through the coastal waters this
afternoon...peaking Monday around 7-8 feet with a period of 17 seconds.
This will result in elevated surf at beaches south of del Mar in San
Diego County...and around Huntington Beach in Orange County. Local
sets of 7-8 feet are expected Monday and Tuesday. Large tidal swings and
elevated surf will create strong rip currents as well. Surf and
swell will subside Wed/Thu. See cfwsgx for details on the beach
hazards statement in effect through Monday evening.
A 6-8 feet short-period northwest swell will move into the outer coastal
waters Monday afternoon and build into portions of the inner waters Monday
night due to a 25-30 knots wind fetch from Point Conception to just
west of San Clemente Island. Combined seas of around ten feet are
likely late Monday/Monday night...resulting in rough seas and hazardous
conditions for small craft. A Small Craft Advisory has been issued
for Monday afternoon through early Tuesday morning. See laxmwwsgx for
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Small Craft Advisory for hazardous seas from 3 PM Monday to 9
am PDT Tuesday for the San Diego County coastal areas.
Wind Advisory from 7 am this morning to 2 PM PDT this afternoon
for the San Diego County mountains...San Diego County
Beach hazards statement through Monday evening for the beaches
in the Orange County coastal areas...San Diego County
Pz...Small Craft Advisory for hazardous seas from 3 PM Monday to 9
am PDT Tuesday 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