Scientific Forecaster Discussion
fxus66 klox 270606
Area forecast discussion...updated
National Weather Service Los Angeles/Oxnard California
1106 PM PDT Fri may 26 2017
night and morning low clouds and fog are expected for the coast
and some valleys through next Friday. Otherwise, clear to party
cloudy skies can be expected through the period. High pressure
will bring warmer temperatures to the area this weekend into
Monday, then low pressure will result in cooler temperatures
Tuesday through late next week.
A deep marine layer remains in place across the area as broader
and weaker troughing over the west brushes the region through
Sunday. A rather muttled stratus pattern is prevalent currently as
viewed by the latest fog product. Low confidence exists in the
cloud forecast through Saturday morning as the a weak marine
inversion exists. Stratus clouds will likely struggle to reform
as a result. The best confidence lies for possible broader
reformation late tonight and into Saturday morning.
Strong onshore flow remains in place this evening. A Wind
Advisory has been extended for the Antelope Valley into early
Saturday morning as strong southwest winds continue, especially
across the foothill areas. Onshore flow should gradually weaken
through weekend bringing warmer and drier conditions.
*** From previous discussion ***
Warming trend to really kick into gear Sunday/Monday as high
pressure develops over the West Coast and onshore flow continues
to weaken. Likely about 10 degrees of warming for inland areas
Sunday and another 3-5 Monday. Low clouds will continue along the
coast and pushing into the lower valleys each morning.
Models now in pretty good agreement showing a trough developing
along the West Coast Tuesday, though differ on how deep it will
develop through the end of the week. The GFS is quite a bit deeper
than the European model (ecmwf) and Gem but consistent with what we saw this week.
Regardless a cooling trend will now begin Tuesday and continue
through Thursday, though the extent of the cooling still remains
to be seen. We should be turning the corner by the very end of the
week as the trough or semi-closed upper low moves east and is
replaced by another ridge. Marine lyr will remain a constant for
the coast during the night and morning hours at least and
for the valleys through mid-morning each day. Overall a pretty
quiet week of weather.
At 00z, the marine layer depth at klax was near 4200 feet. It was
capped by a weak inversion topping out at 6300 feet with a
temperature of 14 degrees celsius.
Low confidence in the current forecast. The deep marine layer
will likely collapse and then reform. There is a 40 percent chc
that low clouds will not reform this morning. If low clouds do
reform there are equal chances of them forming at either 015 025
Klax...low confidence in taf. There is a 40 percent chc of clear
skies through 06z Sunday. If low clouds do reform there are equal
chances of them forming at either 015 025 or 035.
Kbur...low confidence in taf. There is a 40 percent chc of cigs
from 10z-17z. If low clouds do reform there are equal chances of
them forming at either 015 025 or 035.
High confidence in sub-advisory wind speeds and seas through
tonight, then low-end Small Craft Advisory conditions will likely
develop from the central coast to San Nicolas Island late Saturday
afternoon and night. At least, definite Small Craft Advisory
conditions will occur Sunday through Monday with gusts up to 30
knots. Some of the winds will spill into the western half of the
Santa Barbara Channel but likely not enough to warrant a Small
Craft Advisory for the whole channel. These winds will create a
short period chop over all waters including the Santa Barbara
Channel and Santa Monica basin into Monday.
California...Wind Advisory in effect until 3 am PDT Saturday for zone 59. (See laxnpwlox).
Pz...Small Craft Advisory in effect from 3 PM Saturday to 3 am PDT
Sunday for zone 673. (See laxmwwlox).
Hazard potential outlook...(mon-fri)
no significant hazards expected.