Excessive Heat in California, August 8 to 9, 2018

Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
300 AM PDT Wed Aug 8 2018

.SYNOPSIS...
Dry weather and above normal temperatures can be expected over
the area for the remainder of this week as an upper level ridge of
high pressure dominates the weather pattern. Sub-tropical moisture
could move into the region and lead to isolated thunderstorm
development over the higher elevations of the Sierra this weekend.

&&

.DISCUSSION...
Continued hot and smokey conditions are expected over the next
several days across the CENCAL interior. We will see day after day
of bad air quality and hot conditions which already are producing
bad fire weather conditions due to the dry air and poor overnight
RH recoveries. Smoke and haze across the San Joaquin Valley is not
expected to lift anytime soon. Couple that with above normal
temperatures, and it is quite miserable around here. The good news
is that we do not have any new fire starts in the southern Sierra
or Kern county mountains. We are also hoping to see some sub
tropical moisture try to make its way in here for the weekend.
This could bring some isolated showers and possible thunderstorms
to the high country in the Sierra.

Continued progress on fighting the Ferguson Fire in Mariposa
county will only lead to the reduction of smoke production over
the next several days. However, a stagnant weather pattern will
not allow the smoke to clear out. Temps will be hovering around
the century mark for the next several days with some locations
dropping to just below, but it will still be above normal.

Speaking of normal, the normal high temperatures are now starting
to fall and will continue to do so through the rest of the year.
We call it Meteorological Fall. It is slightly ahead of
astronomical fall which occurs September 22 of this year. We will
only fall 4 degrees in August in Fresno, but will see an 8 degree
fall in September for Fresno. It was really nice to see the
normal of 98 for yesterday, compared to the 99's we have been
seeing since July 14. We just need the ridge to break down. But
unfortunately, it won't be anytime soon. But time is on our side
now.

&&

.AVIATION...
Areas of MVFR visibility with local IFR in haze and smoke can be
expected in the San Joaquin Valley, foothills and higher elevations
of the Sierra for at least the next 24 hours. Local LIFR to VLIFR
visibilities in smoke will occur in the vicinity of the Ferguson
wildfire. The areas most affected will be Merced, Madera, Mariposa,
and Tuolumne Counties. Otherwise, VFR conditions will prevail over
the central CA interior during the next 24 hours.

&&

.AIR QUALITY ISSUES...
Please see SFOAQAHNX for an Air Quality Alert.

On Wednesday August 8 2018... Unhealthy for sensitive groups in
Fresno... Kern... Madera and Tulare Counties and Sequoia National
Park and Forest.

Further information is available at Valleyair.org

&&

.CERTAINTY...

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.

&&

.HNX Watches/Warnings/Advisories...
Excessive Heat Warning from 10 AM this morning to 9 PM PDT
Thursday Caz093-099.

&&

public...JDB
avn/fw...BSO
synopsis...JDB

weather.gov/hanford