Scientific Forecaster Discussion
Southwest California area forecast discussion
National Weather Service Los Angeles/Oxnard California
910 am PDT Tuesday Jul 22 2014
High pressure currently over New Mexico will expand west through the
end of the week...resulting in a warming trend and a reduction in
marine layer cloud coverage. Triple digit heat can be expected for
the desert and the hottest valley locations starting Wednesday or
Thursday and lasting through the weekend.
Short term (today-thu)...high pressure expanding westward from the
4 corners region will bring a substantial warming trend to the area
through Thursday. Warmer valley areas will get close to 100 Wednesday then a
few degrees warmer Thursday which should be the warmest day for lower
elevations. Valley High temperature records Thursday are well over 100 so
pretty tough to catch but not completely out of the question.
Coastal area records more within reach, especially sba at only 82.
Marine layer expected to be fairly patchy next few days with
increasing northwest flow developing across the western half of the
***From previous discussion***
Increasing northwest flow will also bring sundowners to the sba South
Coast. A fairly weak event tonight which will be focused on the
Gaviota area. But on Wednesday as the flow becomes a little more
northerly and a little stronger which should bring advisory level
gusts to most of the canyons. This will also likely result in the
some 900pm maximum temperatures for south sba coastal locations.
Long term (fri-mon)...
all 4 days of the extended look very similar and very warm. Both the
GFS and ec agree that the upper high will move further westward and
will dominate the weather during the period. The marine layer
stratus will shrink and will likely be limited to just a few
beaches. Maximum temperatures will be 5 to 8 degrees above normal. Current forecast
does not show any monsoon connection but the upper high placement is
in a position favorable for some sort of monsoon flow. Did not add
any clouds or thunderstorm chances but have to keep an eye on this. This looks
like it may be a pretty good heat siege as the extended models keep
the upper high overhead through day 10. Looking at the fantasyland
extend forecast it shows that the ridge will break down on August 1st.
Overall...moderate confidence in 12z taf package. Latest amdar
soundings indicate inversion based around 1000 feet. Stratus is
struggling to establish this morning...and will likely remain very
patchy this morning. Will keep coastal tafs stratus-free this
morning...although would not be shocked to see a brief period of IFR
ceilings (especially at ksmx). For tonight...will expect any stratus
that develops to remain low (ifr/LIFR levels) and confined to the
Klax...moderate confidence in 12z taf. There is a 30% chance of IFR
ceilings between 12z and 17z this morning. Low confidence in return of
IFR ceilings tonight.
Kbur...high confidence in 12z taf.
For the outer coastal waters...high confidence in the development of
small craft conditions this afternoon and continuing through
Wednesday. Moderate confidence in the development of gale force
winds Wednesday afternoon/night across the southern two outer waters
zones (a gale watch continues this morning).
For the inner coastal waters...moderate confidence in development of
small craft conditions this afternoon and evening across the western
half of the inner waters. Small craft conditions will possibly
continue through Thursday across the western half of the inner
Small Craft Advisory (see laxmwwlox).
Gale watch (see laxmwwlox).