Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 041215
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
415 AM PST Tue Mar 4 2014
Some lingering showers will be possible across the interior of
northern California today. Another weather system will begin to
affect parts of northern California tonight into Thursday. Dry
conditions are expected for Friday and Saturday with another low
pressure system possible on Sunday.
A few showers will linger across the region today as yesterday`s
weather system exits the region. Some areas of the northern
mountains north of Redding and over eastern Butte County saw
between 2.5 and 3 inches of rain during the past 24 hours. Weak
ridging will move over the area today, but moist southwesterly
flow will continue to bring plenty of cloudiness across NorCal.
Satellite imagery shows a nearly continuous stream of clouds
extending from off the coast of NorCal to near Hawaii. Appears
that after a relative break today, precip will begin to return to
the region later tonight and Wednesday as another wave moves up
from the southwest. Increasing warm advection is expected to bring
light to moderate precipitation to the coast range and northern
mountains by early Wednesday.
Appears most precip will remain north of I-80 during the day on
Wednesday before spreading south on Wednesday night as a frontal
zone shifts south through NorCal. Another inch or two of QPF will
be possible over the mountains while the valley is expected to see
generally between 1/4 to 1/2 inch of rain. Snow levels are
forecast to be above 8000 feet during much of the event, so
accumulating snowfall will be along the higher portions of the
northern Sierra crest.
Upper trough shifts over the area Thursday continuing a chance of
showers with snow levels lowering to 5500 to 6500 feet, then more
amplified ridge builds in for Friday and Saturday leading to a
return of dry and milder weather.
.Extended Discussion (Saturday through Tuesday)...
Dry and unseasonably mild conditions continue into Saturday with
Valley highs reaching into the lower to mid 70s. Improving
agreement with extended models showing a shortwave moving through
on Sunday. Some of the moisture from Tropical Storm Faxai,
currently located east of Guam looks like it will be transported
across the Pacific into California. The 06Z GFS shows PW levels
around 1.20 inches extending inland during the day Sunday.
Although dynamics look limited, this could bring a decent amount
of moisture into the mountains. Mild temperatures with this
tropical airmass should mean high snow levels (around 8000 feet),
though, so addition to the snowpack would be limited. Monday looks
less certain, with potentially another wave bringing some more
precipitation, if the ECMWF is correct. The GFS is slower, and
brings this wave in on Tuesday. EK
Widespread MVFR with areas of IFR and local LIFR from low cigs and
br, improving to VFR after 18z with improving visbys and risings cigs.