Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
930 PM PST sun Feb 7 2016
Synopsis... strong high pressure aloft over California will combine
with offshore flow to bring areas of strong gusty northeaxterly
winds...especially below passes and canyons...through Tuesday.
Daytime highs will be well above average under sunny skies.
Gradual cooling will begin along the beaches around mid-week...
spreading inland late in the week as a weak trough moves by to the
north. No precipitation is expected through at least next weekend.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Skies were clear this evening...with areas of east to northeast
winds locally gusting around 50 miles per hour. It remained quite mild...with
middle-evening temperatures still in the 70s in some
locations...especially in urban heat islands...on slopes and in
windy areas. Pressure gradients were 8 mb offshore from Las Vegas to
San Diego...and this could increase to as much as 12 mb by Monday
morning. Winds should peak early Monday morning with local gusts
over 70 miles per hour in windiest locations...mainly below the Cajon Pass and
in the Santa Ana Mountains and foothills...though the west slopes of
the San Diego County mountains will have windy areas as well.
Fullerton had the highest National temperature today at 89...and
temperatures will locally reach near 90 Monday and Tuesday in inland
Orange County and the valleys as the profile will only change
slightly as the offshore flow continues Monday...then weakens
The ridge will continue over California through mid-week...then a
trough will approach the Pacific northwest and weaken the ridge over
our area. We will have a return to onshore flow...and that could
briefly give US some marine layer stratus late in the week...but
moisture sufficient for precipitation will most likely stay to our
north. There will be a cooling trend...though temperatures should
stay above normal in most if not all areas through next weekend.
Models indicate possible ridge building early next week...though GFS
has been indicating the last 2 runs some moisture and an upper low
around next Tuesday which could give US some precipitation. European model (ecmwf)
runs have been keeping US dry then though.
the combination of northeast winds of 25 to 35 miles per hour with higher gusts
in wind-favored areas...and minimum relative humidity of around ten percent Monday and
Tuesday...will create near-critical fire weather conditions for several
hours Monday afternoon and again on Tuesday. However...fuel moisture
levels are not favorable for explosive fire growth...so no fire
weather products are in effect or anticipated at this time.
080400z...unrestricted visible and mostly sky clear through Monday morning. NE
to east winds and associated uddfs/low level wind shear will strengthen in the
mountains...foothills...and passes later this evening through Monday
morning. Surface winds of 25-35 knots with gusts to 50-60 knots are
expected. Low level wind shear likely at ksna and kont during times when wind does
not surface. Kont will likely see sustained winds 15 to 20 knots with
gusts to 35 knots. Ksna will experience slightly weaker sustained winds
but still gusts to around 25 knots.
800 PM...no hazardous marine weather expected through Thursday.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Wind Advisory until 4 PM PST Monday for San Diego County
mountains-San Diego County valleys.
High Wind Warning until 4 PM PST Monday for Orange County inland
areas-Riverside County mountains-San Bernardino County
mountains-San Bernardino and Riverside County valleys-the
inland Empire-San Gorgonio Pass near Banning-Santa Ana
Mountains and foothills.