California, 2020

Dense Fog in California, February 1, 2020

February 1, 2020 · NWS HNX · 2 events in 2 counties and zones

High pressure persisted over the region for another day as February began. Just as during the previous two mornings, dense fog formed toward the center of the San Joaquin Valley and persisted until late morning in portions of Kings and western Fresno Counties.

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
2

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.

High pressure persisted over the region for another day as February began. Just as during the previous two mornings, dense fog formed toward the center of the San Joaquin Valley and persisted until late morning in portions of Kings and western Fresno Counties.

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 Jan 31, 3:43 PM PST, 9 hours 42 minutes earlier.

Area forecast discussion, Jan 31, 3:43 PM PST, 9 hours 42 minutes before
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Event by event

2 dense fog. Local standard time, as filed.

Dense Fog, Foggy Bottom

When
February 1, 1:25 AM PST to 9:35 AM PST
Where
Foggy Bottom forecast zone
Reported by
ASOS

Visibility below a quarter mile was reported in Hanford.

Dense Fog, Tulare County

When
February 1, 6:45 AM PST to 7:40 AM PST
Where
Tulare County forecast zone
Reported by
AWOS

Visibility below a quarter mile was reported in Visalia.

What these are

Dense Fog
Fog reducing visibility to a quarter mile or less, filed where it caused accidents or disruption.

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

The same day elsewhere

More

Every storm in California in 2020Every state in 2020This day in weather historyWarnings in California, February 2020

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 2026-10-01. Each event’s entry at NCEI: 867253, 867254.