Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
FXUS66 KHNX 202232
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
232 PM PST Fri Jan 20 2017
.SYNOPSIS...The second storm in a series of storms will exit east
of the state this evening. In its wake, scattered showers will
linger in the lower elevations through Saturday with snow showers
continuing over the mountains. The next storm will bring another
round of rain and mountain snow to the region Saturday night into
Monday. A drying trend will begin Tuesday with a continuation of
dry weather for the remainder of next week.
.DISCUSSION...Storm #2 delivered a wet punch to the central
California interior today and brought accumulating snow as low as
the 2500 foot elevation in the Kern County mountains this
afternoon and to elevations generally above 3500 feet farther
north over the Sierra. Strong and gusty southerly winds ahead of
the cold front associated with this storm system have since abated
in the San Joaquin Valley but will continue until about dusk over
the Grapevine where a cold rain has been falling much of the day.
The heaviest precipitation has been falling ahead of the cold
front but will shut off pretty quickly once it exits east of
Tulare County and Kern County early this evening. Until then,
these areas will remain the primary focus of urban and small
stream flooding and road flooding. Precip with this system arrived
so fast across Kern County this morning that colder air that was
trapped in the mountain valleys did not have enough time to warm
up. Residents in the communities of Wofford Heights, Bodfish and
Lake Isabella were dumped on with a small accumulation of snow
today. In the southern Sierra, this storm has brought several
inches of snow between 4k ft and 6k feet. Meanwhile, snow has
been accumulating by the foot at higher elevations of the Sierra.
The upper level trough associated with this storm system will
exit east of the CWA later this evening. By then, most if not all
of the shower activity will have ended in the San Joaquin Valley.
Scattered showers will linger over the higher terrain into
Saturday. A break, albeit brief, from wet weather is expected
Saturday afternoon into Saturday evening before storm #3 spreads
its precipitation into the CWA Saturday night. This final storm
in the series will be a little wetter and a little colder and
take a little longer to move through the Golden State than the
previous two storms. Prior to its arrival, strong and gusty
southerly winds will likely develop again over the northern San
Joaquin Valley and along the west side of the San Joaquin Valley
late Saturday night. The bulk of this third storm`s precip will
fall Sunday afternoon into Sunday night, during which time very
heavy snow is expected over the high Sierra. Snow levels will
start out from 5500 feet in the Sierra to 7000 feet in Kern
County, then lower abruptly Sunday night as this storm moves
inland. By Monday morning, snow levels will lower to about 2000
feet in the Sierra to 3500 feet in Kern County, so foothill
locations as well as the Kern County mountain passes will be at
risk for potentially hazardous wintry travel conditions by then.
In the lower elevations, additional rainfall on top of already
saturated ground will bring a renewed threat of flooding during
the second half of this weekend.
The upper level trough associated with this third storm will
move inland over central California Monday afternoon, during
which time the air will become cold and unstable enough for
isolated thunderstorms with small hail in the San Joaquin Valley
and lower foothills. Showers should diminish Monday evening
over the lower elevations but likely continue over the higher
terrain into Tuesday morning as the upper level trough shifts
eastward into the Great Basin.
A northerly flow will gradually bring a drier air mass into the
CWA Tuesday. During the remainder of next week, an upper level
ridge of high pressure will build in over California and bring
mostly clear skies and a gradual day to day warming trend.
Night and morning fog will make a comeback in much of the San
Joaquin Valley during this period.
SAN JOAQUIN VALLEY...Isolated thunderstorms possible through 06z
Saturday. Otherwise MVFR conditions in with isolated showers.
SIERRA NEVADA AND KERN COUNTY MOUNTAINS...Widespread mountain
obscurations and scattered showers through 18z Saturday. Strong gusty
over mountain ridges.
KERN COUNTY DESERT...Areas of MVFR in rain showers until 06z
Saturday. Strong gusty winds below the mountain passes until 18z
Otherwise VFR conditions can be expected elsewhere across the
central California interior during the next 24 hours.
.AIR QUALITY ISSUES...
The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is medium.
Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.php for additional information
an/or to provide feedback.
Winter Storm Warning until 10 AM PST Saturday CAZ096-097.
Winter Weather Advisory until 4 AM PST Saturday ABOVE 5000 FEET
FOR THE CAZ095.