California, 2011

Dense Fog in California, December 29 to 31, 2011

December 29 to 31, 2011 · NWS SGX · 2 events in 2 counties and zones

A shallow marine layer resulted in areas of dense fog along the coastal areas in Orange County, the San Diego coastal mesas and the Western San Diego County valleys. Visibility was a below a quarter mile in many locations for several hours in the overnight and early morning periods from the 29th through the 31st.

Where it happened

Every event with a place to put it; 1 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
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 SGX wrote it up.

A shallow marine layer resulted in areas of dense fog along the coastal areas in Orange County, the San Diego coastal mesas and the Western San Diego County valleys. Visibility was a below a quarter mile in many locations for several hours in the overnight and early morning periods from the 29th through the 31st. Operations at John Wayne and San Diego International Airports were impacted for several hours both nights.

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 Dec 29, 9:15 PM PST, 1 hour 45 minutes earlier.

Area forecast discussion, Dec 29, 9:15 PM PST, 1 hour 45 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Hazardous weather outlook, Dec 29, 3:15 PM PST, 7 hours 45 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The radar

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

Open the radar archive at this moment

Event by event

2 dense fog. Local standard time, as filed.

Dense Fog, Orange County Coastal Areas

When
December 29, 11:00 PM PST to December 31, 11:55 PM PST
Where
Orange County Coastal Areas forecast zone
Reported by
ASOS

The John Wayne Airport ASOS reported visibility of less than one-quarter mile from 2318 PST on the 29th through 0439 PST on the morning of the 30th. Visibility of one-eighth of a mile was reported from 2229 to 2317 PST on the night of the 30th and again on the morning of the 31st from 0553 to 0652 PST and from 0721 to 0947 PST. Visibility of one-eighth of a mile was again reported the evening of the 31st from 1823 to 1852 PST and again from 2053 to 2352 PST.|The Newport Beach lifeguards also reported visibility of less than 100 yards on the morning of the 31st.

Dense Fog, San Diego County Coastal Areas

When
December 29, 11:00 PM PST to December 31, 7:00 AM PST
Where
San Diego County Coastal Areas forecast zone
Reported by
ASOS
Coordinates
33.028, -116.770 (the zone’s center; the record gives no point)

The San Diego Lindbergh Field ASOS reported visibility of one-eighth of a mile from 0351 to 0528 PST on the morning of the 30th and again on the morning of the 31st from 0201 to 0250 PST. |Zero visibility was reported at nearby Coronado Cays near Chula Vista.

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 2011Every state in 2011This day in weather historyWarnings in California, December 2011

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 2026-09-30. Each event’s entry at NCEI: 356798, 356799.