167
FXUS66 KHNX 022040
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
140 PM PDT Tue Jul 2 2024


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.KEY MESSAGES...
1. Above average temperatures continue today, then rapidly warm
up to around 15 degrees above normal by Wednesday. This is a
dangerous, prolonged heat wave that will last several days with
an Extreme Heat Risk.

2. An Excessive Heat Warning remains in effect from Tuesday,
July 2nd through Wednesday, July 10th at 8am, and may need to be
extended further as the week progresses.

3. The risk of grass fires will continue to increase with
herbaceous fuel loading at or near 120% of normal. A long period
of excessive heat, minimum relative humidities near 15% and poor
overnight relative humidity recoveries will add to the grass
fire risk.

&&

.DISCUSSION...
The multi-day heatwave has begun today as the high pressure
begins moving over California off the Pacific coast. This high
pressure system will stay nearly stationary over California for
at least the next week, with some long range guidance suggesting
impacts from this high pressure system will last through late
next week at least. This high pressure system sitting almost
stationary over the state will allow temperatures to build at
the surface, leading to a dangerous, long-duration heatwave
statewide.

In particular, the San Joaquin Valley looks to see temperatures
hovering around 110 degrees for a few days beginning tomorrow.
Probabilities that areas within the San Joaquin Valley will see
temperatures greater than 110 rise to a 45 percent chance or
above by Saturday, July 6th, from 10-35 percent Wednesday
through Friday of this week. These probabilities stay very
similar to Sunday. Thus, the two hottest days of the heat wave
will be this Saturday and Sunday. Here are probabilities that
select cities within the forecast area will see 110 degrees or
more as a high temperature for Saturday, July 6th.
Bakersfield: 75%
Coalinga: 85%
Fresno: 60%
Hanford: 65%
Madera: 45%
Merced: 45%
Ridgecrest: 96%
Visalia: 80%

Low temperatures will also be very high for this time of year,
with many locations within the valley expected to see values
above 70 degrees through the duration of the heatwave. High
minimum temperatures lead to poor overnight temperature
recovery. Due to these factors, there is extreme HeatRisk
forecasted to be widespread throughout the valley beginning on
Thursday and lasting at least through next Tuesday. An extreme
level of HeatRisk means that the entire population is at very
high risk for heat-related illnesses if they do not have access
to adequate cooling and hydration. Some safety measures to take
include: wearing lightweight clothing, drinking water or sports
drinks, and staying inside during the hottest hours of the day.
Due to this extreme heat risk, an Excessive Heat Warning has
been issued for the San Joaquin Valley, West Side Hills, and the
Kern County Mountains and Desert. This warning began today at
11am and will continue through next Wednesday, July 10th, at
8am. Should temperatures around 110 degrees continue to be
forecast for the valley beyond next Wednesday, the warning will
be extended as necessary.

The Climate Prediction Centers long range outlooks are not
offering much relief. Both the 6-10 day and the 8-14 day outlook
show the San Joaquin Valley with a higher than 50 percent chance
of seeing above average temperatures continue through July 12th.

&&


.AVIATION...
Continued areas of MVFR and local IFR visibility due to smoke at
and around the Fresno County fires will continue in the Sierra
Nevada and adjacent foothills. Otherwise, VFR conditions will
prevail across the central California interior for the next 24
hours.

&&

.FIRE WEATHER...
Above normal temperatures, low relative humidities, poor
overnight humidity recovery, and dry fuels will continue. The
impact issue this afternoon and evenings starting Wednesday into
the weekend will feature wind gusts into the teens for the
region to add to the fire weather impacts. The best news is that
the probability of thunder is near zero for the period ahead.

&&

.AIR QUALITY ISSUES...
ISSUED:  07/01/2024 14:37
EXPIRES: 07/02/2024 23:59
None.



&&

.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.html for additional information
and/or to provide feedback.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
Excessive Heat Warning until 8 AM PDT Wednesday for CAZ300>322-
324-332-334-336>339.
&&

$$

public/aviation...AS
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