Dense Fog in California, January 14, 2021

Name: Dense Fog in California, January 14, 2021
Start: 2021-01-14T00:10
End: 2021-01-14T01:55
Location: California

January 14, 2021 · NWS HNX · 1 event in 1 county or zone

High pressure remained dominant over central California for several days. Clear skies and light winds prevailed across the San Joaquin Valley during the afternoon and evening of January 13.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

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 remained dominant over central California for several days. Clear skies and light winds prevailed across the San Joaquin Valley during the afternoon and evening of January 13. By the early morning of January 14, areas of dense fog formed along the State Route 99 corridor between Madera and Turlock. The fog lifted into a low cloud deck before sunrise.

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 13, 5:11 PM PST, 6 hours 59 minutes earlier.

Area forecast discussion, Jan 13, 5:11 PM PST, 6 hours 59 minutes before

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Event by event

1 dense fog. Local standard time, as filed.

Dense Fog, Merced and Madera

When: January 14, 12:10 AM PST to 1:55 AM PST
Where: Merced and Madera forecast zone
Reported by: ASOS

Merced reported visibility below a quarter mile.

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

Every storm in California in 2021 Every state in 2021 This day in weather history Warnings in California, January 2021

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: 928792.