California, 2002

Dense Fog in California, March 31, 2002

March 31, 2002 · NWS SGX · 4 events in 3 counties and zones

Dense fog with visibility near zero, formed over the inland valleys.

Where it happened

Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
4

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 SGX wrote it up.

Dense fog with visibility near zero, formed over the inland valleys.

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 San Diego, CA wrote its last area forecast discussion before the first event at Mar 30, 9:25 PM PST, 2 hours 35 minutes earlier.

Area forecast discussion, Mar 30, 9:25 PM PST, 2 hours 35 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

4 dense fog. Local standard time, as filed.

Dense Fog, X W San Diego Valley

When
March 31, 12:00 AM PST to 8:53 AM PST
Where
X W San Diego Valley forecast zone
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
33.028, -116.770 (the zone’s center; the record gives no point)

Dense Fog, X Sw San Bernardino

When
March 31, 1:00 AM PST to 8:53 AM PST
Where
X Sw San Bernardino forecast zone
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
34.293, -116.086 (the zone’s center; the record gives no point)

Dense Fog, W Riverside T X Nw

When
March 31, 2:00 AM PST to 8:53 AM PST
Where
W Riverside T X Nw forecast zone
Reported by
AWOS,ASOS,MESONET,ETC

Dense Fog, X W San Diego Valley

When
March 31, 10:24 PM PST to 11:59 PM PST
Where
X W San Diego Valley forecast zone
Reported by
AWOS,ASOS,MESONET,ETC
Coordinates
33.028, -116.770 (the zone’s center; the record gives no point)

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 2002Every state in 2002This day in weather historyWarnings in California, March 2002

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: 5281729, 5281730, 5281731, 5281732.