Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
FXUS66 KHNX 272249
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
349 PM PDT FRI MAY 27 2016
Warmer and drier weather today except for a few showers and possibly
an isolated afternoon and early evening thunderstorm along the
Sierra Crest. System moves into the region on Saturday which will
increase chances of afternoon/evening showers and thunderstorms for
the mountains through Sunday. High pressure will move in beginning
Memorial Day bringing a return to drier and much warmer conditions
through most of next week.
Temperatures are warming several degrees from 24 hrs ago under
generally sunny skies across interior central California, as a
shortwave ridge builds ahead of a weak disturbance approaching in
the northwesterly flow aloft. Afternoon highs are on track to top
out a few degrees above climo today. Radar is beginning to show a
few thunderstorms popping near the Sierra crest as the atmosphere
remains moderately unstable there.
The approaching shortwave impulse is progged to spin up a weak low
over central California by Saturday which then drops slowly
southeast through Sunday. With sufficient moisture and this
destabilizing low pressure feature, we should see more convective
development over the mountains, extending into Kern County,
Saturday and Sunday. Despite this weak transiting low, temperature
trends should continue a slight increase over the next couple of
days as lower levels continue to warm.
Memorial Day will see a ridge of high pressure begin building
inland as the weak low moves away from the region. This will bring
high temperatures near 10 degrees above normal as flow becomes
more offshore, while mountain convection decreases. Expect just a
few thunderstorms near the Sierra crest, with most activity likely
to be east of the crest.
As the ridge continues to build overhead, we can expect further
warming through the middle of next week. Some of the warmest
Valley locations could reach triple digits, with no more than a
few thunderstorms anticipated near the Sierra crest.
Another approaching trough will possibly bring some relief for the
latter part of next week as the upper ridge is nudged eastward.
There are differences amongst the model solutions with the
strength, timing and trajectory of this feature, but for now it
looks like it will at least bring temperatures down a few degrees
for Thursday and Friday.
Areas of MVFR and local IFR in showers and isolated thunderstorms
over the southern Sierra Nevada from 20Z today through 04Z Saturday.
Otherwise, VFR conditions will prevail in the central CA interior
for 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.