High Wind and Strong Wind in California, December 4 to 5, 2018

Name: High Wind and Strong Wind in California, December 4 to 5, 2018
Start: 2018-12-04T12:13
End: 2018-12-05T08:00
Location: California

December 4 to 5, 2018 · NWS HNX · 4 events in 2 counties and zones

The toll

Deaths: 0
Injuries: 0
Property damage: $1,000
Crop damage: None recorded
Events: 4

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS HNX wrote it up.

A large low pressure system dropped slowly southward off the California coast on December 4 and 5. This resulted in a strong offshore pressure gradient over central California which produced strong winds in the downslope prone areas in Kern County. Several reports of peak gusts exceeding 40 mph were reported in the Kern County Mountains and the south end of the San Joaquin Valley between the late morning of December 4 through the early morning of December 5.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Hanford, CA wrote its last area forecast discussion before the first event at Dec 4, 3:40 AM PST, 8 hours 33 minutes earlier.

Area forecast discussion, Dec 4, 3:40 AM PST, 8 hours 33 minutes before

Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
340 AM PST Tue Dec 4 2018

.SYNOPSIS...
A storm system will bring a return of wet weather to the region
starting tonight and continuing off and on through Thursday night.
Clearing conditions are expected for the weekend.

&&

.DISCUSSION...
Light precipitation starting to fall across the northern portion
of the district this morning. Based on gauge and Doppler radar
analysis, current precipitation rates are very light and amounting
to mostly trace amounts. Measurable precipitation is very spotty
this morning ahead of the main precipitation band. The weather
disturbance associated with this mornings precipitation is
currently located about 400 miles due west of the Bay Area and
slowly drifting south by southeast. While the heaviest
precipitation is not currently in the district, locally strong
winds have warranted the issuance of a wind advisory for the
Grapevine area today as speeds reach 50 mph today. For the next 24
hours or so, will watch as the track of the current disturbance
move toward the Southern California area.

Models showing the upper low moving from about 400 miles west of
the Bay area near the Channel Islands by Thursday morning. While
confidence is high on the current trajectory, confidence is
precipitation amounts will remain low. If the upper low maintains
its offshore track, significant precipitation accumulation will
not be favored over the district for the next 24 to 48 hours. A
tight temperature (and pressure) gradient from the Mojave to
Bakersfield will generate strong winds over the Kern County
Mountains. Surface observations from the Grapevine area are
already indicating 40 to 50 mph winds this morning. A wind
advisory is currently in effect for that area. As for
precipitation, will not issue any advisories for winter weather as
a few to several inches of new snow is expected above 5000 to 6000
feet MSL in the coming 48 hours. Lighter amounts may be possible
below the 5000 foot mark with liquid equivalent values of 0.40 to
0.60 of an inch during the same time-span.

Upper low still expected to dig into the Desert Southwest and
Northern Mexico by the end of the week. This shift will allow a
ridge of higher pressure to enter the region. While this ridge
will sit over the West Coast for several day, another disturbance
will shift the ridge pattern east as unsettled conditions return
the region. Timing of the next storm is set for early next week.
Models show another disturbance entering the region on Sunday with
an increasing potential for precipitation closer to Monday. At the
moment, will keep precipitation probabilities at chance levels
until better consensus can be reach on next weeks storms.

&&

.AVIATION...
Local MVFR/IFR conditions in precipitation over the Southern
Sierra Nevada. Otherwise, even in light precipitation, will
expect mainly VFR conditions to prevail across the central
California interior for the next 24 hrs.

&&

.AIR QUALITY ISSUES...
On Tuesday December 4 2018...Fireplace/Wood Stove Burning Status
is: No Burning Unless Registered in Kings County. 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.html for additional information
an/or to provide feedback.

&&

.HNX Watches/Warnings/Advisories...
Wind Advisory until 8 PM PST this evening CAZ095.

&&

public...Molina
avn/fw...Dudley
synopsis...Molina

weather.gov/hanford

In the hours before

Local storm report, Dec 4, 10:44 AM PST, 1 hour 29 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HANFORD CA
1044 AM PST TUE DEC 4 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1013 AM     NON-TSTM WND GST 3 SSE GRAPEVINE         34.90N 118.90W
12/04/2018  M64 MPH          KERN               CA   MESONET

            MESONET STATION GVPC1, GRAPEVINE PEAK.

&&

DS

Event by event

3 high wind, 1 strong wind. Local standard time, as filed.

High Wind, Kern Cty Mtns

When: December 4, 12:13 PM PST
Where: Kern Cty Mtns forecast zone
Measured: 60 kt (69 mph) measured gust
Reported by: RAWS

The Grapevine Peak RAWS reported a peak wind gust of 69 mph.

High Wind, Kern Cty Mtns

When: December 4, 6:50 PM PST
Where: Kern Cty Mtns forecast zone
Measured: 56 kt (64 mph) measured gust
Reported by: Mesonet

Cummings Valley reported a peak wind gust of 65 mph.

Strong Wind, Kern Cty Mtns

When: December 4, 7:00 PM PST
Where: Kern Cty Mtns forecast zone
Measured: 48 kt (55 mph) estimated gust
Property damage: $1,000
Reported by: Public

Public report in Bear Valley Springs of an Italian cypress tree that snapped 2/3 of the way up. The diameter was 6-8 inches at the location of the break.

High Wind, Se S.J. Valley

When: December 5, 8:00 AM PST
Where: Se S.J. Valley forecast zone
Measured: 50 kt (58 mph) measured gust
Reported by: Mesonet

The California Highway Patrol station in Grapevine reported a peak wind gust of 58 mph.

What these are

High Wind: Sustained non-thunderstorm winds of 40 mph or more for an hour, or gusts of 58 mph or more.
Strong Wind: Non-thunderstorm winds below high wind criteria that nonetheless caused damage or casualties.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in California in 2018 Every state in 2018 This day in weather history Warnings in California, December 2018

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 788237, 788238, 788659, 788236.