Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
920 PM PDT Sat Oct 25 2014
a trough of low pressure move inland across the West Coast through
Sunday...bringing cooler conditions and gusty west winds to the
mountains and deserts. High pressure will then rebuild over the
west...with dry and warmer conditions developing for the work week.
Another trough will move inland across the West Coast for next
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
The upper level trough continues to trek inland across the West
Coast this evening. Patchy low clouds were developing over the San
Diego County coastal areas...otherwise skies were clear. Onshore
surface pressure gradients continue to strengthen...currently at
about 6 mb san-ipl and 3.3 mb san-dag. Winds are gusting into the
low 30 miles per hour range in the favored locations in the low deserts.
Patchy low clouds will slowly develop west of the mountains tonight
into Sunday morning. The inversion will be fairly weak with the
cooler air aloft moving in...so expect stratus to be somewhat
unorganized. Otherwise...cooler conditions will develop for Sunday
with local gusty winds continuing in the mountains and deserts. A
few high clouds will pass over the region at times...and overall it
should be a pleasant day.
As this trough shifts east...high pressure will slowly rebuild along
the West Coast into midweek. Only minor warming will occur Monday as
we remain under dry west-northwest flow. Some patchy low clouds will
redevelop west of the mountains Sunday night and possibly Monday
night into Tuesday. The ridge amplifies for Tuesday and Wednesday
with very weak offshore flow in the mornings...bringing warmer and
drier conditions. Low clouds may linger over the coastal waters
during the nights and mornings...otherwise mostly clear conditions
will prevail. Wednesday will be the warmest day as the ridge moves
directly overhead...with minor cooling following Thursday as the
ridge shifts east and onshore flow begins to redevelop.
Extended range models remain in fairly good agreement regarding the
forecast for late in the week. A large Pacific trough should move
across the West Coast over the weekend...though exact timing is a
little uncertain. Should see a greater cooling trend Friday into the
weekend with gusty onshore winds developing in the mountains and
deserts and more widespread night and morning low clouds and fog.
There could even be some...Dare I say it...light precipitation. As
usual the models are showing the front totally falling apart by the
time it reaches US...so it does not look too promising...but it is
also not out of the realm of possibilities. Confidence is way too
low to include mention of any precipitation in the forecast...but thought I
would at least give you a glimmer of hope in the meantime.
260330z...coast/valleys...bkn low clouds with bases 1500-2000 feet
mean sea level...and tops 2000-2500 feet mean sea level will slowly develop inland 25-35
miles through 14z Sunday. Low to moderate confidence in broken low
clouds arriving at coastal taf sites between 05z and 09z. Visible
restrictions to 3 sm or less will occur where low clouds intersect
higher terrain...with visible restrictions to 5 sm possible at kont
after 10z. Low clouds will clear back to the coast between 16z and
19z Sunday morning. Few at or above 1500 feet mean sea level along the immediate coast
from 20z Sunday to 04z Monday.
Mountains/deserts...periods of high clouds at or above 15000 feet mean sea level.
Otherwise...sky clear with unrestricted visible through Sunday evening.
830 PM...a northwest swell peaking at 9 feet 14 seconds will begin to impact
the outer waters in and around San Clemente Island by Sunday
morning. Sustained winds of 10-14 kts with gusts near 20 kts will
accompany the swell. At this time it appears conditions will
approach...but not exceed Small Craft Advisory criteria for the
outer waters. Both the swell and wind will decrease rapidly on
Monday...with no hazardous marine weather conditions expected
through Thursday evening.
830 PM...a northwest swell...near 7 feet at 14 seconds will begin arriving
along non island shadowed beaches by Sunday morning. When combined
with a 2 feet south swell at 17 seconds...surf of 3-6 feet...and local
sets of around 8 feet along exposed west-northwest facing beaches
are likely. Highest sets will impact locations in and around
Huntington Beach...and exposed west facing beaches of southern San
Diego County. A beach hazard statement for elevated surf and a high
risk of rip currents will take effect Sunday morning.
Skywarn activation will not be needed today.
California...beach hazards statement from Sunday morning through Sunday
evening for the Orange County coastal areas...San Diego
County coastal areas.