Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
133 PM PDT Friday Aug 29 2014
elevated to high surf will continue...subsiding throughout the
day today. Weakening upper-level high pressure will allow cooling
to begin along the coast....but continue warming for inland areas
through Saturday. A pattern change will begin on Sunday with
cooler weather and a deeper marine layer...with even cooler
conditions developing middle to late next week.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
At 1 PM PDT...water vapor satellite imagery displayed an upper-
level ridge centered around 175 miles west-southwest of San
Diego...and an upper-level low associated with the remnants of
Post-tropical cyclone Marie around 900 miles west of San Diego.
Visible satellite showed clear skies across southwestern
California...except for a few areas of stratus just off of the San
Diego County coast. Temperatures were a few degrees cooler along
the coast and valleys...and a few degrees warmer in the mountains
and deserts compared to this time yesterday.
The upper-level ridge will slowly flatten and traverse southwest
throughout the weekend. Although cooler weather will prevail along
the coast through the weekend as the marine layer
redevelops...warm weather will continue well inland through
Saturday...with high temperatures a few degrees above normal. A
weak shortwave trough moving southeast to our north will create
breezy westerly winds to 40 miles per hour Saturday afternoon and evening
over the high deserts.
Dry flow aloft will then transition southwesterly as a very broad
upper-level ridge develops over the southern contiguous United
States early next week. This will help create a deeper marine
layer...a weak coastal eddy and high temperatures near to and
below normal. By the middle of next week...the upper-level high
will shift more to the east as a trough digs along the West Coast.
The 29/1200 GFS and European model (ecmwf) are in good agreement with the pattern
through the middle of next week...but then diverge in agreement
next weekend in the placement of the trough in the far extended.
The likely outcome will be high temperatures 5 to 15 degrees f
below normal...a very deep marine layer...and breezy westerly
winds in the mountains and deserts to close out next work week.
Models do hint at a possible return of monsoonal moisture next
weekend over eastern Southern California as the aforementioned
upper-level high moves westward...possibly creating southeasterly
flow over the region. However...this could also be inhibited by
the trough along the West Coast if models forecast a continuance of
292008z...coast/valleys...through 30/0300 UTC...unrestricted
visibility and mostly clear skies. 30/0300-1400 UTC...stratus
gradually moving inland 10-15 miles...with bases around 800-1200 feet
above mean sea level...tops around 1300-1500 feet above mean sea level
and areas of visibility 3-5 miles. Confidence in timing of stratus
arrival to ksan...kcrq and ksna is low-to-moderate. Confidence in
ceiling height forecast is moderate-to-high. 30/1400-1800
UTC...stratus clearing to the Coast.
Mountains/deserts...mostly clear skies and unrestricted visibility
through Saturday morning.
108 PM...no hazardous marine weather expected through Tuesday.
108 PM...latest buoy reports from the near shore waters indicate that
the south swell from tropical cyclone Marie has fallen to around 3-5
feet with 10 second intervals. The swell will continue to diminish
through the day...but surf of 5-7 feet with sets to 8 feet is
possible for Orange County...and actually still being reported
according to the morning surfline observations...so a high surf
advisory remains in effect for that area. Strong rip currents and
elevated surf will also continue for San Diego County...where a
beach hazards statement remains in effect. No significant swells are
expected after today. For details...see cfwsgx and srfsgx.
spotter activation will not be needed today.
California...high surf advisory until 8 PM PDT this evening for the beaches
in the Orange County coastal areas.
Beach hazards statement until 8 PM PDT this evening for the
beaches in the San Diego County coastal areas.