Northerly flow behind a cold frontal passage during the evening of February 2 resulted in low clouds banking up against the valley facing slopes of the Tehachapi Mountains. This resulted in areas of dense fog reducing visibility to below 200 feet which adversely impacted travel along State Route 58 near Tehachapi and Interstate 5 near Lebec and Fort Tejon.
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.
Northerly flow behind a cold frontal passage during the evening of February 2 resulted in low clouds banking up against the valley facing slopes of the Tehachapi Mountains. This resulted in areas of dense fog reducing visibility to below 200 feet which adversely impacted travel along State Route 58 near Tehachapi and Interstate 5 near Lebec and Fort Tejon. California Highway Patrol paced traffic on both highways as a result of the dense fog.
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 Feb 3, 3:16 AM PST, 3 hours 14 minutes earlier.
Area Forecast Discussion National Weather Service Hanford CA 316 AM PST Wed Feb 3 2021 .SYNOPSIS... A cold front passing through the district will bring gusty conditions over the higher terrain of the Sierra Nevada and the wind prone areas of Kern County today. A dry pattern is expected to set up after today for several days with above average afternoon highs by this weekend. && .DISCUSSION... Latest GOES-17 reveals a cold front passing through the region this morning, but it's lacking moisture. The QPF that was being advertised by models over the last few days did not materialize over the Sierra Nevada this morning, so we cancelled the Winter Weather Advisory early. However this system will still be capable of bringing gusty winds over parts of the high country as well as wind prone areas of Kern County today. We have trimmed back the area of the Wind Advisory over the Sierra Nevada (excluded the North Kings River zone) and pushed it back to start at 6 AM; it now expires at 4 PM. The Wind Advisory for Kern County has been pushed back to 8 AM, still expiring at 7 PM. Additionally, the upslope flow along the north and west slopes of the Tehachapi Mountains may set up for some drizzle through the early afternoon. This is being depicted by high resolution models forecasting very light QPF in the south valley. After the system pushes through, a dry weather pattern is being forecast by blended model guidance as high pressure builds over the Eastern Pacific. For us, we will experience a few days of cool, northwesterly flow allowing for cool mornings. Thursday morning through Saturday morning are likely to have frost, especially in the lowest elevations of the valley. Ridging over the weekend will allow for a minor warming trend. Afternoon highs in the mid 60s are conceivable across the San Joaquin Valley through early next week along with continued dry weather. Dry conditions and above average temperatures are forecast to continue into early next week. && .AVIATION... Mountain obscuration in north and west slopes of the Tehachapi Mountains through 00z Thursday. Otherwise, VFR conditions will prevail across the central CA interior for the next 24 hours. && .AIR QUALITY ISSUES... None. && .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 from 8 AM this morning to 7 PM PST this evening for CAZ196>199. Wind Advisory from 6 AM this morning to 4 PM PST this afternoon for CAZ194-195. && public...Bollenbacher aviation....Bollenbacher weather.gov/hanford
2 dense fog. Local standard time, as filed.
California Highway Patrol reported visibility below 200 feet in fog in Tehachapi and paced traffic along SR 58. Webcams in Tehachapi showed very low visibility in fog.
California Highway Patrol reported visibility below 200 feet in fog along the Tejon Pass and the Grapevine area paced traffic along I-5. Webcams along I-5 indicated very low visibility in fog.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2021Every state in 2021This day in weather historyWarnings in California, February 2021
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: 931765, 931766.