Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
FXUS66 KHNX 281030
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
330 AM PDT Fri Apr 28 2017
Breezy conditions will continue across the region this Friday.
Lighter winds, warming temperatures and dry weather will then
prevail this weekend into early next week as high pressure
strengthens over the region.
Strong winds will continue to influence the weather over the
Central California Interior as another disturbance moves through
the area. The continuation of an active spring pattern will be
observed this Friday as the location of the strong winds change
from Kern County to most of the San Joaquin Valley. Analysis of
the upper air is showing the amplification of the flow aloft as an
upper low over Utah digs further south toward the four corners
area. This digging of the upper low will allow the flow pattern
aloft to take a more northerly direction over California as models
prog the introduction of a +130kt jet max into the Western Great
Basin. At the surface, cold air surging into the Pacific
Northwest/Great Basin will shift the thermal trof offshore and
tighten the pressure gradient from north to south. In addition,
this shift in the pressure gradient will not affect the desert as
much as the Central Valley, which will also have jet max support
during the day. Therefore, will go ahead and allow the Wind
Advisory to expire at 5 AM PDT. Will then issue a Wind Advisory
for the San Joaquin Valley from this morning through 11 PM PDT
Short range models show the upper low moving further east on
Saturday as weak ridging moves into the region. Jet max support
moves into Arizona as winds over California diminish. 500mb
heights which have been rising on Saturday will continue to rise
on Sunday. Therefore, confidence in lowering winds and rising
temperatures will increase during the latter part of the weekend
as models maintain their trend of developing a west coast ridge
pattern early next week. Even as weak disturbance rides over the
ridge pattern and into the Pacific Northwest/Inter-mountain West,
models still show the ridge pattern trending toward further
strengthening. By Wednesday of next week, models place the
slightly tilted ridge axis over the west coast as temperatures
continue to rise. Current thinking on track with forecast as
peaking heating is expected around the mid-week period. In
addition, while confidence is low with a disturbance expected next
Thursday, will at least increase cloud cover and lower
temperatures for that time frame.
Strong surface winds gusts expected this Friday as speeds
could reach 35 knots across the San Joaquin Valley and adjacent
foothills down to Kern County. Otherwise, VFR conditions will
prevail across the Central CA Interior during the next 24
hours -- except for a few spots where clouds may produce MVFR
.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.
Wind Advisory from 8 AM PDT this morning until 11 PM PDT this
evening across the Central and Southern San Joaquin Valley