Summit, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

880
FXUS66 KHNX 151105
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
405 AM PDT Tue Apr 15 2025

.UPDATE...
Aviation Section Updated

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.KEY MESSAGES...
1. Unseasonably warm temperatures will continue through this
week with highs approaching 15 degrees above average today.

2. Breezy conditions are expected for the Mojave Slopes through
the week, peaking on Thursday.

3. There is a slight chance for showers and thunderstorms
across the Sierra Nevada each afternoon Tuesday through Friday.

4. There is a Marginal Risk (at least 5%) for excessive rainfall
in the Sierra Nevada on Wednesday.

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.DISCUSSION...
Central California is currently under the influence of a ridge,
which will result in well above average temperatures today,
though a small area of lower pressure spinning off the
California coast is causing an influx of high level moisture
into the region, resulting in high cirrus clouds over our CWA.

This area of low pressure is then expected to interact with a
weak trough coming in from the Pacific Ocean, leading to a
stronger trough that will move over California from Tuesday
through Thursday. This will bring in more moisture from the
ocean and possibly lead to thunderstorm development over the
Sierra Nevada each afternoon during that time period, with the
chances for thunderstorms expanding to the Northern San Joaquin
Valley on Wednesday. The Weather Prediction Center has also
has the Sierra Nevada and it`s foothills under a Marginal Risk
(at least 5%) of excessive rainfall, mainly due to expected PWAT
values to be around 0.75 inches, which is well above normal and
in the 95 percentile of the climate average. This carries the
risk of rapid snowmelt due to high snow levels of 9 to 10K feet
on that day.

Moving to Thursday and Friday of this week, another trough
dropping down from Canada is expected to fuse with the Tuesday
trough and continue the possibility for thunderstorms in the
mountains, and could expand the area of those storms if the
trough drops down further south. Rain chances for the Valley
will also increase during this time as the added energy and
moisture may lead to precipitation further to the west with the
incoming system.

With each of these systems, temperatures will be pulled down to
around normal and even slightly below normal in some places from
Tuesday through Friday. Then a small ridge is expected to build
in over the weekend and cause a warming trend once again.

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.AVIATION...
12Z Update

VFR Conditions will prevail over the central California interior for
the next 24 hours.

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.AIR QUALITY ISSUES...
ISSUED:  04/14/2025 14:07
EXPIRES: 04/15/2025 23:59
None.



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.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.

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.HNX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

aviation....Proton

weather.gov/hanford