Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
FXUS66 KHNX 202240
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
240 PM PST Mon Feb 20 2017
A significant storm continue to impact Central California today,
bringing abundant precipitation and strong winds to the area.
These conditions may exist through at least Tuesday. Otherwise,
unsettled weather through Wednesday with a return to wet weather
Storm currently pushing through California as moderate to heavy
precipitation has been observed throughout the day. While
Northern California is currently in the trajectory of the
atmospheric river plume, parts of Central California have received
significant amounts. The atmospheric river is being steered by a
cold front pushing southeast into California today. The timing of
the cold frontal passage through the region is likely place the
bulk of the atmospheric moisture over the district later tonight
into early Tuesday morning. Therefore, will expect the
precipitation to continue tonight as additional abundant moisture
surges into the region. Currently, winter storm warnings and flood
watches and advisories are in effect for today`s unsettled
conditions. Both Oakland and Vandenberg upper air observations
show over an inch of precip-water (which are over 200 percent of
normal for this date). Therefore, support exist for the
continuation of moderate to heavy precipitation across Central
California from tonight into Tuesday.
Of a bigger concern for the start of the week is the current
hydrologic conditions of the region. The current storm continues
to causes problems for area rivers and other water control
facilities that are running at or near capacity. Therefore,
confidence is high that the latest precipitation accumulation will
cause problems. River statements and flood products have been
posted as rivers and many creeks reach levels that may threaten
life and property across Central California.
Models continue to show higher confidence levels that cyclonic
flow will remain over the West through most of the week.
Therefore, unsettled conditions will linger beyond the short term
as precipitation may exist over the West Coast (off and on)
through most of the next seven days. One thing to note is that
models currently show no atmospheric river type event occurring in
the next seven days. Yet, models do show a good plume of moisture
that may allow for a good precipitation potential between
Saturday night into Sunday. Therefore, will the mention of higher
than climo probability of precipitation for next weekend as
ingredients starting to come into phase for yet another storm.
By next weekend, longer range models still showing an upper low
dropping down along the Pacific Northwest/Northern California
(NorCal) Coast. Uncertainty is still very high, but models do
indicate the existence of the upper low off the NorCal Coast
during the day on Saturday and Sunday. Will return to a wet
pattern by Saturday as the possibility exist for even more
.AVIATION...VFR over the San Joaquin Valley today with local
gusty winds to 35 knots. Areas MVFR ceilings over foothills and
Sierra through 18z Tuesday. VFR conditions will prevail 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.
Flood Watch through Tuesday morning CAZ089-090-093-094-096-097.
Winter Storm Warning until 10 AM PST Tuesday ABOVE 7000 FEET FOR
Wind Advisory until 7 AM PST Tuesday CAZ089-090-093.