Upper level high pressure remained over California as December began and fog formed along the center of the San Joaquin Valley as skies remained clear and winds remained light. Areas of dense fog formed again in the San Joaquin Valley, most noticeably in Hanford where law enforcement was pacing some traffic.
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.
Upper level high pressure remained over California as December began and fog formed along the center of the San Joaquin Valley as skies remained clear and winds remained light. Areas of dense fog formed again in the San Joaquin Valley, most noticeably in Hanford where law enforcement was pacing some traffic.
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 Nov 30, 3:35 PM PST, 10 hours 55 minutes earlier.
Area Forecast Discussion National Weather Service San Joaquin Valley - Hanford CA 335 PM PST Thu Nov 30 2017 .UPDATE...Updated air quality issues. && .SYNOPSIS...Dry weather and near normal temperatures will continue over the central California interior through Saturday. Sunday through Tuesday will be dry but cooler in the wake of a cold frontal passage Saturday night. && .DISCUSSION...A dry westerly flow prevails over central California, while a low pressure system moves over the Pacific Northwest and northern California. The primary effect with this system is expected to be a few high clouds over our region. In the San Joaquin Valley, the fog and low clouds from this morning have dissipated, and high temperatures will rise to slightly above average. However, expect at least some patchy dense fog to redevelop tonight and Friday morning and again Friday night into Saturday as weak upper-level high pressure ridging will return. Another low pressure system is expected to arrive by Saturday night; forecast guidance continues to show relatively little moisture with this system. We have kept the slight chance POPs for Yosemite and the nearby Sierra Nevada and adjacent foothills during Saturday night and Sunday, as the latest model runs show decent agreement in terms of a slight uptick in probabilities over this area. Most of the moisture and dynamics will move over the Pacific Northwest and northern CA. A broad ridge of high pressure will build just off the coast of the western U.S. during early next week, including Monday and Tuesday. Temperatures will likely fall to around seasonal averages or slightly below during this period, though guidance has trended a bit warmer in terms of daily low temperatures. A drier airmass is expected over the area, so lows will likely be relatively cold in portions of the Kern County desert (lower to mid-20s in a few locales), at least on Tuesday morning, as the upper-level trough behind the Sat night/Sunday system moves over the Great Basin and southward over the desert regions of southeastern California. In addition, temperatures are expected to warm back up to several degrees above average by Wednesday and next Thursday as the ridge moves inland. A relatively dry airmass will prevail over the region, so no precipitation is expected through much of next week. Given the time of year (i.e., the first week of December), nighttime and morning fog will remain a possibility over the San Joaquin Valley. && .AVIATION...In the San Joaquin Valley, widespread MVFR visibility in haze with areas of IFR in haze and mist and local LIFR visibility in fog between 08Z Fri and 20Z Fri. Otherwise, VFR conditions will prevail over the central CA interior during the next 24 hours. && .AIR QUALITY ISSUES... On Friday December 1 2017... Unhealthy for sensitive groups in Fresno County. Fireplace/Wood Stove Burning Status is: No Burning Unless Registered in Fresno... Kern... Kings... Madera... Merced and Tulare 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.php for additional information an/or to provide feedback. && .HNX Watches/Warnings/Advisories... NONE. && public...BSO avn/fw...DS synopsis...BSO weather.gov/hanford
1 dense fog. Local standard time, as filed.
Visibility below a quarter mile was reported in Hanford. California Highway Patrol was pacing traffic in State Route 198 through Hanford eastward to the Tulare County border during the morning commute. The fog completely dissipated by late morning.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2017Every state in 2017This day in weather historyWarnings in California, December 2017
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: 723881.