Area Forecast Discussion
Issued by NWS San Joaquin Valley, CA
FXUS66 KHNX 281004
Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
304 AM PDT THU JUL 28 2016
A ridge of high pressure continue to bring hot temperatures through
the weekend. Afternoon and early evening showers and thunderstorms
are possible along the Sierra crest today and through the weekend
and will possibly spread into the Kern County mountains and desert
by the weekend.
A strong ridge of high pressure over the southwestern CONUS and
the Great Basin will continue to be the prevailing weather feature
for our area the next few days. High temperatures will continue to
be in the triple digits in the San Joaquin Valley, southern
Sierra foothills and Kern County deserts. After a very hot day
Wednesday, temperatures are expected to be degree or two warmer
today most areas. This will put max temperatures in the San
Joaquin Valley near 110 degrees. However, the airmass remains
fairly dry with heat indices expected to remain several degrees
below the actual temperature.
Meanwhile, some moisture has worked its way into the Sierra
Nevada. A few thunderstorms formed over the higher elevations
yesterday afternoon. With the moisture in place and models
indicating a little more instability today, expect thunderstorms
again this afternoon and early evening. Thus, have increased the
pops to the chance category and expect them to spread a bit
farther north than yesterday.
Little change in airmass expected through Friday as the ridge
remains parked just to the east of our area. Daytime temperatures
will continue to run 7-10 DEG F above normal Friday with enough
instability and high based moisture to continue with a chance
afternoon and early evening thunderstorms near and along the
southern Sierra crest.
The medium range models continue to indicate that the ridge will
weaken slightly over the weekend as a low pressure system moves
across western Canada and the Pacific Northwest, flattening the
ridge a bit. This will allow temperatures to edge down a few
degrees over the weekend. However, we will still remain in the
triple digits, but mainly between 100 and 105 in the San Joaquin
There is still the possibility of some mid level moisture
pushing into southern California by the weekend which might allow
for a few diurnal showers and thunderstorms over the Kern County
mountains and deserts as well as over the southern Sierra Nevada.
A second shortwave trough will move into the Pacific Northwest
Monday and Tuesday. This should turn the flow aloft southwesterly
which would push the moisture eastward, ending the threat of
thunderstorms. Temperatures are expected to run slightly above
normal for the beginning of August.
Cumulus buildups and isolated thunderstorms are expected over the
Sierra Nevada this afternoon and evening, otherwise VFR conditions
can be expected through Central California for at least the next 24
.AIR QUALITY ISSUES...
On Thursday July 28 2016... Unhealthy in Fresno... Kern and Tulare
Counties and Sequoia National Park and Forest. Unhealthy for
sensitive groups in Kings... Madera and Merced Counties.
Further information is available at Valleyair.org
The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is high.
Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.php for additional information
an/or to provide feedback.