FXUS66 KSGX 181222

Area Forecast Discussion
National Weather Service San Diego CA
415 AM PST Sun Nov 18 2018

High pressure aloft will bring dry, warm weather today and Monday
with variable high clouds. A weak trough will develop off the coast
next week and move inland Wednesday and Thursday. Rain is likely
over Northern California by Wednesday, and there is a chance for
light rain over Southern California Wednesday night and Thanksgiving
Day. The holiday weekend outlook is for generally dry weather with
temperatures at or a little below average.



Like yesterday morning, low level offshore drainage winds returned
again this morning and kept widespread low clouds and fog from
forming in the coastal zones. Mid and high clouds from over the
Pacific continued drifting across the region this morning.

High pressure aloft and weak to moderate offshore flow will keep us
dry through Monday. There will be little in the way of low clouds,
but plenty of mid and high clouds. On Tuesday a weak trough will
bring minor cooling and a better chance for coastal low clouds and

The weather gets a little more interesting Wednesday and Thursday
when much of the West Coast will see rain and high elevation snow.
The main focus for the most significant precipitation will be in
northern and central California where a Pacific trough makes
landfall. The trough weakens as it moves south and the precipitation
amounts will taper off here in SoCal. Nevertheless, some light
precipitation is possible Wednesday night and Thursday morning when
the Precipitable Water maxes out at 1.10". The ECMWF has been
consistently stronger and with more precipitation than the GFS, but
the QPF should come into better focus in the next couple of days.

The flow aloft remains mostly high-zonal after the passage of the
holiday trough, keeping temperatures seasonal, and humidity levels
elevated in a fairly deep marine layer. The passage of additional
weather systems to the north may even squeeze some drizzle or light
rain from the marine layer west of the mts at times through next
weekend, but significant rainfall amounts seem unlikely at this time.


181030Z...Coastal...Patchy BKN stratus will continue to develop this
morning, with bases around 1000-1800 ft MSL and tops to 2000 ft MSL.
Local vis 1-3 miles could occur over higher coastal terrain and
coastal valleys where low clouds develop. Otherwise, mostly BKN high
clouds at/above 20000 ft MSL will prevail through tonight.

Valleys/Mountains/Deserts...Mostly BKN high clouds at/above 20000 ft
MSL will prevail through tonight with unrestricted vis.


No hazardous marine weather is expected through Thursday.


High pressure over the Great Basin will bring light to moderate
offshore winds today and Monday. Afternoon humidities will fall into
the teens in the valleys and mountains elevating the fire weather
threat, especially with such dry fuels in place. The flow turns
onshore Tuesday and Wednesday and humidities will slowly recover. A
trough may bring light rain Wednesday night and Thursday.


Skywarn activation will not be needed through Tuesday.






Chino Hills, Ca. Weather | www.ChinoHillsWeather.com