Irwin, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

957
FXUS66 KHNX 040538 AAA
AFDHNX

Area Forecast Discussion...UPDATED
National Weather Service Hanford CA
938 PM PST Tue Dec 3 2024


.UPDATE...
Updated AVIATION section.

&&

.KEY MESSAGES...

1. Dry weather will prevail through next week with above average
temperatures.

2. Nighttime and morning fog, locally dense in the early
morning, remains possible every day through next week for the
San Joaquin Valley.

&&

.DISCUSSION...

A low pressure system currently sits over much of central
California that was previously off the coast of southern
California. The cyclonic flow around the trough is pushing the
upper level atmospheric flow to the south of the region, with an
area of higher pressure to our north pushing flow through the
Pacific Northwest. This upper level pattern is creating stagnant
conditions aloft, resulting in dry conditions with minimal
precipitation over the area. Conditions are conducive for Tule
Fog each overnight and morning period in the San Joaquin Valley
through much of this week due to this blocking upper level
pattern. Clearing conditions each day will allow the surface and
soil moisture to evaporate overnight, condensing at the surface
in large part due to minimal winds and subsiding air aloft.
Visibilities across the valley will generally be less than a
quarter mile with localized areas experiencing less than 200
feet.

Dry, stable conditions are expected to prevail through much of
the week, with temperatures a few degrees above normal for this
time of the year. A slight cooldown is expected to happen on
Friday as the aforementioned low pressure system digs deeper
into the desert southwest region. The Cyclonic flow around the
system will shift winds to the north, pulling in cooler air from
the Pacific northwest. Temperatures will warm up slightly for
Saturday as a shortwave ridging pattern sets up for the day. The
following are probabilities from the National Blend of Models
to reach or exceed 65 degrees each day through Thursday for
various locations of the San Joaquin Valley.

               Tuesday Wednesday Thursday Friday Saturday
Bakersfield      60%      75%      40%      20%     50%
Coalinga         85%      90%      90%      60%     75%
Fresno           45%      45%      25%       4%     15%
Hanford          55%      50%      40%      20%     20%
Madera           60%      75%      40%      20%     20%
Merced           60%      65%      40%      15%     20%
Visalia          25%      35%      30%       5%     10%

Cluster analysis and model ensemble output expresses a stronger
trough dropping south into the western United States early next
week. The flow around the trough will shift winds from the north
again, albeit stronger than the system before the weekend,
pulling in cooler air from western Canada. Afternoon
temperatures are anticipated to be in the upper 50s and near
normal for this time of year. Morning lows will approach the mid
to lower 30s, which is below season averages. As the cooler air
will originate over continental Canada, little moisture will be
associated with the system, with little to no precipitation
outside of the highest elevations of the Sierra Nevada.

&&


.AVIATION...
Widespread IFR visibility in mist across the San Joaquin Valley
becoming areas of LIFR/VLIFR in fog by 09Z Wednesday. Becoming
IFR/MVFR in mist/haze after 19Z Wednesday.

High Sierra/Foothills/Kern County Desert: VFR few high clouds
for the next 24 hours.

&&

.AIR QUALITY ISSUES...
On Wednesday December 4 2024, Unhealthy in Kern, Kings, and
Tulare Counties. Unhealthy for Sensitive Groups in Fresno and
Madera Counties. Fireplace/Wood Stove Burning Status is: No
Burning For All in Fresno, Kern, Kings, Madera, and Tulare
Counties. No Burning Unless Registered in Merced County. Burning
Discouraged in Kern (Greater Frazier Park Area) and Sequoia
National Park and Forest.

&&

.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...
Dense Fog Advisory from 1 AM to noon PST Wednesday for CAZ302-
303-306-307-310>312-314-315.

&&

$$

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