Scientific Forecaster Discussion
fxus66 klox 241025
Area forecast discussion
National Weather Service Los Angeles/Oxnard California
325 am PDT Fri Mar 24 2017
a weakening cold front may bring light rain and to the area late
Friday into early Saturday. A mainly dry inside slider may bring
gusty northerly winds and a reinforcing shot of cooler air. Weak
ridging aloft and northerly winds at the surface will likely bring
warm and dry conditions for the middle of next week.
Skies are currently mostly clear save for a little bit of stratus
over the la coast. There are some clouds associated with a weak
trof to the northwest of slo County. These clouds will begin to move into
the central coast later this morning. The morning marine layer
stratus pattern for la County remains unclear. The forecast eddy
that was supposed to help the low cloud formation has not really
started up yet. There is a chance that the stratus will not form.
The next problem for today is the rain that will come with the
weak front. All mdls have trended slower with this system and
timing has been pushed back accordingly. The front is currently
north of San Francisco it will push down the coast and rain should
start over the northwest tip of slo County late this afternoon. Clouds
will slowly increase through the day becoming partly cloudy south
of pt Conception and mostly cloudy north.
Rain will continue to move to the south and east overnight
tonight. Rain will fall on slo and sba County and it will likely
reach Ventura County by dawn. There is a chance that it will reach
The front will wash out on Saturday. There will be a chance of
showers in the morning but by afternoon the skies will turn partly
cloudy over most of the area and the clouds and showers will be
confined to the north slopes.
A little pop up ridge will move in Sunday, skies will be partly
cloudy at worst but most likely they will be mostly sunny.
Max temps really will not change that much from day to day. Every
days will see Max temps a couple degrees blo normal with Saturday
a degree or two cooler than today and Sunday.
All mdls agree that an inside slider will move through on Monday.
The mdls have been waffling back and forth with just how inside
this system will be...currently all mdls agree that the system
will be far enough inside to limit shower chances to the mtns and
the interior vlys. Rainfall will be spotty and light. The bigger
issue will be the winds that will arrive with the cool air behind
the system. It looks like there will be strong advisory level
north winds across the mtns and into the vlys as well as the sba
South Coast. Max temps will change little from Sunday.
Tuesday and Wednesday will be dominated by ridging...offshore flow
and much warmer than normal Max temps. Look for 5 to degree jump
in temps on Tue and then for another 3 to 6 degrees on Wed. Wed
Max temps will likely be 10 to 15 degrees above normal.
The ridge will break down next Thursday. The GFS replaces it with
dry northwest while the ec swings a big cool trof over the area. Right
now forecast favors the gentler GFS soln.
At 0545z, there was no marine inversion present at klax.
Moderate confidence in tafs. Stratus will likely develop towards
dawn less confidence in exact timing or hgts. Clearing could be
off by an hour. Rain timing could be off by up to 2 hours for the
central coast. Good confidence in earlier arrival of stratus
Klax...moderate confidence in taf. Stratus could arrival as early
as 09z. Hgts could be off by +/- 500 feet. Good confidence in
early arrival of stratus tonight.
Kbur...good confidence in taf. There is a 20 percent chc of MVFR
Winds and seas have fallen below Small Craft Advisory criteria. However, a few
local gusts to 25 kt cannot be ruled out through early this
morning from san nicolas to Santa Rosa islands. Patchy fog is
possible to the south of Point Conception this morning with a weak
Wind will likely increase again on Saturday. There is a 70
percent chance Small Craft Advisory winds will prevail across the outer waters
Saturday through Tuesday. There will be periods of gale force
winds...with a 40 percent Saturday night and 60 percent chance
Monday into Tuesday. Small Craft Advisory to gale force winds may also extend into
the inner waters at times during this period, with the strongest
winds likely Monday afternoon and evening. Gusty winds may
continue across the outer waters through much of next week.
California...beach hazards statement in effect until 9 am PDT this morning
for zones 40-41-87. (See laxcfwlox).
Hazard potential outlook...(sun-thu)
a weak rain event is expected through Saturday, with minimal
High surf and strong rip currents are likely Friday into
Early next week, a stronger storm system is expected and could
bring gusty northerly winds and mountain snow.