Interaction between an upper ridge over the west coast and an upper low pressure system that dropped southward from the Great Basin into the Desert Southwest region produced a period of gusty easterly winds over the Kern County Mountains between the evening of December 2 and the late morning hours of December 3. Several stations in the Tehachapi and Fort Tejon areas measured gusts exceeding 40…
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.
The episode as NWS HNX wrote it up.
Interaction between an upper ridge over the west coast and an upper low pressure system that dropped southward from the Great Basin into the Desert Southwest region produced a period of gusty easterly winds over the Kern County Mountains between the evening of December 2 and the late morning hours of December 3. Several stations in the Tehachapi and Fort Tejon areas measured gusts exceeding 40 mph, and a few utility company stations measured gusts exceeding 55 mph. Downslope effects also produced increased winds over the south end of the San Joaquin Valley where several stations measured gusts exceeding 35 mph.
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 2, 10:00 PM PST, 1 hour earlier.
Area Forecast Discussion National Weather Service Hanford CA 1000 PM PST Wed Dec 2 2020 .UPDATE... Winds have started a tad earlier than expected so have opted to expedite the Wind Advisory to start now and go through 4 PM Thursday afternoon. && .PREV DISCUSSION... /issued 433 PM PST Wed Dec 2 2020/ SYNOPSIS... High temperatures this afternoon will be around five degrees above normal for this time of year. Strong, gusty winds are likely in the Kern County mountains tonight. These strong, gusty winds should bleed into the far southern portion of the San Joaquin Valley Thursday. Extremely dry conditions are expected in the Kern County mountains Thursday and Friday. DISCUSSION...Another clear day across the Central California Interior with a patch of cloudiness moving along the west side of the valley today. Otherwise, clear and dry conditions will allow for warm days and very cold nights as near freeze values will be observed for several more days. While most of the district will continue to see light winds, the area in Kern County around the Tehachapi range from Lake Isabella to Frazier Park will see stronger winds for the next 24 or so hours as a Santa Ana winds event hits Southern California. Winds during the next 24 hours will reach wind advisory criteria while humidity lowers across the same area. Therefore, a wind advisory is current in effect for the Kern Mountains through Thursday afternoon. Afterward, the lack of moisture across the same area will allow a Red Flag Warning for high fire danger to exist. That warning will remain in effect until Friday evening. Beyond that, near normal temperatures and dry conditions will persist for the period. Once the current weather disturbance causing the strong Santa Ana conditions exits the region, weak high pressure will shift onto Central California. Therefore, with the high pressure ridge over California on Saturday, will see little change in temperatures and humidity, but no winds that would affect fire conditions. Therefore, quiet for one day before another wind event occurs. Model upper-air analysis places a 100 knot jet just to the northwest of the district with +90 knots crossing the area Sunday night. Downward transfer may allow for breezy conditions through the evening and possibly into the early hours of Sunday into Monday. While the orientation of the jet will lean more toward a “Mono- type” wind direction, strong overnight winds may exist over Central California with limited moisture. Therefore, winds will be more of an issue going into early Monday than the potential for precipitation. Moreover, the northerly winds may dry-out the atmosphere slightly and allow for the lowering to dew- points and lead toward another possible Red Flag event. Will see if model confidence continues to grow in the direction of Mono winds for the Sierra Nevada. While mist may continue for several more days the period of strong north orientation winds with enough downward motion may hinder the development of fog across the San Joaquin Valley for most of the period. Dense fog may not be a factor across the area and will therefore not mention fog overnight and maintain the wording of a near freezing for several mornings. AVIATION... VFR conditions will prevail late this morning into early tonight. MVFR with Local IFR visibility due to mist will likely occur again over parts of the San Joaquin Valley during the overnight hours. AIR QUALITY ISSUES... On Thursday December 3 2020... Unhealthy for sensitive groups in Fresno... Kern and Kings Counties. Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Madera... Merced and Tulare Counties. No Burning For All in Fresno... Kern and Kings Counties. 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... Red Flag Warning from 6 AM Thursday to 6 PM PST Friday for CAZ299-596-597. Wind Advisory until 4 PM PST Thursday for CAZ189-196-197. && update...Andersen public...Molina aviation....Dudley weather.gov/hanford
3 high wind. Local standard time, as filed.
The Southern California Edison station at Cummings Valley measured a peak wind gust of 59 mph.
The PG&E station at Pampa Peak measured a peak wind gust of 72 mph.
The Southern California Edison station at Rancho Ridge measured a peak wind gust of 59 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2020Every state in 2020This day in weather historyWarnings in California, December 2020
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: 923383, 923386, 923388.