Alert archive / Minnesota / Dense Fog Advisories in 2012

Dense Fog Advisory 12, NWS Twin Cities, MN

December 13, 201221 counties in Minnesota; 6 counties in Wisconsin

NWS Twin Cities, MN issued this dense fog advisory at Dec 13, 2012, 9:37 PM CST for 21 counties in Minnesota; 6 counties in Wisconsin. It was in force for 10 hr.

The area

The counties it named.

The facts

Issued: Dec 13, 2012, 9:37 PM CST (03:37 UTC)
Expired: Dec 14, 2012, 8:00 AM CST
In force: 10 hr
Issued by: NWS Twin Cities, MN

All 27 counties

Anoka County, MN, Benton County, MN, Chippewa County, MN, Chisago County, MN, Douglas County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, Lac qui Parle County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Pope County, MN, Sherburne County, MN, Stearns County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Washington County, MN, Wright County, MN, Barron County, WI, Chippewa County, WI, Dunn County, WI, Eau Claire County, WI, Polk County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 64 km from the middle of the area, began a volume at 03:40 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.6 hours before the alert went out and 63 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 792 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: -121 m²/s²
0-3 km storm-relative helicity: 52 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Twin Cities, MN wrote its last area forecast discussion before this dense fog advisory went out at Dec 13, 6:14 PM CST, 3 hours 23 minutes earlier.

Area forecast discussion, Dec 13, 6:14 PM CST, 3 hours 23 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 13, 9:21 PM CST, 16 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
921 PM CST THU DEC 13 2012

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
150330-
DOUGLAS-TODD-MORRISON-MILLE LACS-KANABEC-STEVENS-POPE-STEARNS-
BENTON-SHERBURNE-ISANTI-CHISAGO-LAC QUI PARLE-SWIFT-CHIPPEWA-
KANDIYOHI-MEEKER-WRIGHT-HENNEPIN-ANOKA-RAMSEY-WASHINGTON-
YELLOW MEDICINE-RENVILLE-MCLEOD-SIBLEY-CARVER-SCOTT-DAKOTA-
REDWOOD-BROWN-NICOLLET-LE SUEUR-RICE-GOODHUE-WATONWAN-BLUE EARTH-
WASECA-STEELE-MARTIN-FARIBAULT-FREEBORN-POLK-BARRON-RUSK-
ST. CROIX-PIERCE-DUNN-PEPIN-EAU CLAIRE-
921 PM CST THU DEC 13 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND
SOUTHERN MINNESOTA...AND WEST CENTRAL WISCONSIN.

.DAY ONE...TONIGHT

AREAS OF DENSE FOG WITH VISIBILITIES OF ONE QUARTER MILE OR LESS
WILL BE PRESENT OVERNIGHT ACROSS MUCH OF CENTRAL MINNESOTA AND
WEST CENTRAL WISCONSIN. IN ADDITION TO THE SIGNIFICANT VISIBILITY
REDUCTIONS...SLICK SPOTS ARE POSSIBLE ON ROADWAYS AND UNTREATED
SURFACES DUE TO SUB-FREEZING TEMPERATURES.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A WINTRY MIX OF PRECIPITATION CONTINUES TO APPEAR LIKELY FROM
LATE FRIDAY NIGHT INTO SATURDAY EVENING ACROSS THE OUTLOOK AREA AS
AN AREA OF LOW PRESSURE TRACKS FROM IOWA INTO WISCONSIN.
PRECIPITATION WILL LIKELY START OUT AS RAIN OR FREEZING
RAIN...DEPENDING ON THE SURFACE TEMPERATURE FOR A PERIOD FROM LATE
FRIDAY NIGHT INTO SATURDAY MORNING FROM SOUTH CENTRAL INTO EAST
CENTRAL MINNESOTA AND WESTERN WISCONSIN. IT WILL THEN TRANSITION
TO ALL SNOW FROM WEST TO EAST DURING THE DAY SATURDAY. STAY TUNED
TO FUTURE OUTLOOKS FOR REFINED DETAILS ON THIS DEVELOPING SYSTEM.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION WILL NOT BE NEEDED.

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 14, 4:37 AM CST	Winter Weather Advisory	MPX	Benton, Chippewa, Chisago, Douglas, Isanti, Kanabec and 11 more	43 hr

Nearby

Dense Fog Advisories in Minnesota, 2012 Dense Fog Advisories in Wisconsin, 2012 Every dense fog advisory in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.