Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Diego California
127 PM PST Friday Feb 5 2016
a high pressure ridge aloft will build over the west through early
next week...bringing fair weather and increasingly warmer days.
Gusty offshore winds mainly in the passes...canyons and coastal
foothills will continue...with winds strongest Sunday night into
Monday. The combination of offshore flow and the strong ridge will
boost temperatures well above normal for this time of year...with
Tuesday being the warmest day. Cooling will begin Wednesday and
continue through next Friday as the ridge and offshore flow weakens.
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
Afternoon visible satellite shows predominantly clear skies across
Southern California while water vapor satellite indicates upper
ridging from the west moving over California. Looking at the 12z
Miramar sounding and comparing it to yesterdays...it is clear that
there has been significant warming through most of the layer up to
400 mb. The warming of the air mass is due to the building ridge
aloft. This...in addition to stronger offshore flow...brought much
warmer conditions this morning compared to yesterday. 8 am
temperatures were 10-20 degrees higher than 8 am yesterday in many
Right now...the offshore pressure gradients from San Diego to
Tonopah are up to 12.3 mb...and 11.3 mb from San Diego to Salt Lake
City. Thus...we are continuing to see gusty northeast to east winds
in the passes/canyons and coastal foothills...with several places
reaching 40-50 miles per hour currently. Sill Hill in the San Diego County
mountains has had the highest gust so far...reaching 68 miles per hour at 3 am
this morning. Cansac-WRF indicates gusty winds continuing at about
this strength through the afternoon before winds weaken a little
this evening through early Saturday morning before another pulse of
winds occurs later Saturday morning into the early afternoon hours.
A Wind Advisory for the mountains...valleys...San Gorgonio
Pass...and inland Orange County continues through Saturday morning.
Offshore pressure gradients back off a little later Saturday...and
then models show the gradients increasing again Sunday morning...and
increasing further Monday morning up to 15-18 mb from San Diego to
Tonopah...and 22-25 mb from San Diego to Salt Lake City. At the same
time...better upper level support of northeast 25-40 knots 850 mb winds
arrive. Thus...Sunday night through Monday evening looks like when
the strongest and most widespread northeast to east winds will occur.
During the time of strongest winds...we could see areas of wind
gusts reaching 50-60 miles per hour through and below the passes/canyons and
into the coastal foothills...with the windiest spots possibly
reaching 75 miles per hour. 30-40 miles per hour gusts could reach into the western
valleys and portions of the coast as well. The gradients weaken on
Tuesday and weaken further on Wednesday...resulting in weaker and
weaker offshore winds.
The ridge will continue to build through Tuesday which...in addition
to persistent gusty offshore winds...will result in increasingly
warmer days. Current temperatures are several degrees higher than
24 hours ago across the forecast area. Day-time highs should reach
several degrees above normal in many areas today...and then 10-20
degrees above normal Sunday...and possibly 15-20...and locally 25
degrees...above normal Monday through Tuesday. Tuesday looks like it
will be the warmest day...with highs in the middle to upper 80s in the
valleys and inland coastal areas...middle 70s at the beaches...70s for
the high deserts and Lower Mountain slopes...low 80s in the lower
deserts...and 60s in the high elevations. A few spots may even touch
90 degrees Monday and Tuesday. A weakening ridge and weakening
offshore flow will result in a gradual cooling trend Wednesday
through next Friday.
052100z...NE-E surface wind gusts of 25-35 knots will continue below
passes/canyons/coastal mountain slopes through the weekend. Areas of moderate
uddfs and low level wind shear are possible over/west of the mountains...including near kont
and ksna. Otherwise...mostly clear with a few high cirrus and
unrestricted visible through Saturday.
100 PM...no hazardous marine weather is expected through Tuesday.
100 PM...a west-northwest swell of 290 degrees peaked at 9 feet/18 second
this morning and will slowly decrease through tonight. Surf 3 to 6
feet with sets to 7 feet is expected along west-facing beaches north
of Newport Beach and south of del Mar through this evening with
strong rip currents also likely. A beach hazards statement remains
in effect through 10 PM this evening. Swell and surf will continue
to subside Saturday.
Skywarn activation is not requested. However weather spotters are
encouraged to report significant weather conditions.
California...Wind Advisory until 1 PM PST Saturday for Orange County inland
areas-Riverside County mountains-San Bernardino County
mountains-San Bernardino and Riverside County valleys-the
inland Empire-San Diego County mountains-San Diego County
valleys-San Gorgonio Pass near Banning-Santa Ana Mountains
Beach hazards statement until 10 PM PST this evening for Orange
County coastal areas-San Diego County coastal areas.