Merced, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

185
FXUS66 KHNX 161200
AFDHNX

Area Forecast Discussion
National Weather Service Hanford CA
359 AM PST Tue Dec 16 2025

.UPDATE...
Aviation Section Updated.

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.KEY MESSAGES...

1. Fog, while dense at times, and low clouds will continue each
night and morning across the San Joaquin Valley into the
foothills up to 1,500 feet through Tuesday.

2. Above average temperatures will continue across the
mountains and desert until Tuesday, as the high pressure
pattern persists over the region.

3. Precipitation makes its return to Central California by the
middle of the week after having a dry start to December, with a
more substantial pattern change by this weekend through the
Christmas holiday.

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.DISCUSSION...
The consistent stable pattern over the southwest will continue
through at least the beginning of next week, with strong ridging
keeping the low stratus clouds in place for the center of the
San Joaquin Valley with dense fog on the edge of the Valley from
elevations of 500 feet to 1500 feet. This stratus will also
lower further down during the nighttime hours and lead to fog in
the Valley itself.

A small pattern change is likely in store for Central
California, with the ridging over the Southwest weakening
somewhat as a small trough passes through the Pacific Northwest.
This weaking may lead to slight troughing in Northern California
into Central California, which may lead to a small amount of
precipitation for the northern-most Counties in our CWA, mainly
in Mariposa County and Yosemite Nation Park. This small
disturbance may also provide elevated winds aloft to break the
inversion over the Valley and lead to the stratus deck clearing
out, though it`s unclear if those winds will be strong enough.

Confidence has increased for a more significant pattern change
for Central California this weekend into next week, with the
ensemble models consistently showing a large trough moving
through the west coast by this Saturday through the 26th of
December. The Climate Prediction Center has also highlighted
the 22nd of December through the 26th for a high risk (>60%) of
heavy snow in the Sierra Nevada, and moderate risk (40-60%) of
heavy precipitation for the Sierra Foothills and Coastal Range
for the 23rd through the 25th.

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.AVIATION...
IFR to LIFR ceilings and visibilities are expected to prevail for
much of the San Joaquin Valley during the next 24 hours, with a 40
to 50 percent chance of VLIFR in dense fog between 12Z and 19Z
Tuesday. IFR to LIFR conditions will also persist in the coastal
ranges, Sierra foothills, and the Kern County mountains due to low
clouds. Otherwise, VFR conditions will prevail in the Sierra Nevada
and in the Kern County mountain and desert areas over the next 24
hours.

&&

.AIR QUALITY ISSUES...
ISSUED:  12/15/2025 15:26
EXPIRES: 12/16/2025 23:59

On Tuesday December 16 2025, Fireplace/Wood Stove Burning
Status is: No Burning Unless Registered in Fresno, Kern, and
Madera Counties, and Kern (Greater Frazier Park Area). Burning
Discouraged in Kings, Merced, and Tulare Counties, and Sequoia
National Park and Forest.

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.CERTAINTY...

The level of certainty for days 1 and 2 is medium.
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.
&&

$$

public...EW
aviation....McCoy

weather.gov/hanford