Alert archive / Minnesota / Dense Fog Advisories in 2012

Dense Fog Advisory 4, NWS La Crosse, WI

February 2, 20125 counties in Wisconsin; Floyd County, Mitchell County, Iowa; 6 counties in Minnesota

NWS La Crosse, WI issued this dense fog advisory at Feb 2, 2012, 1:52 PM CST for 5 counties in Wisconsin; Floyd County, Mitchell County, Iowa; 6 counties in Minnesota. It took effect at Feb 2, 2012, 6:00 PM CST. It was in force for 18 hr.

The area

The counties it named.

The facts

Issued: Feb 2, 2012, 1:52 PM CST (19:52 UTC)
In effect from: Feb 2, 2012, 6:00 PM CST
Expired: Feb 3, 2012, 12:00 PM CST
In force: 18 hr
Issued by: NWS La Crosse, WI

Counties Floyd County, IA, Mitchell County, IA, Dodge County, MN, Fillmore County, MN, Mower County, MN, Olmsted County, MN, Wabasha County, MN, Winona County, MN, Buffalo County, WI, Clark County, WI, Jackson County, WI, Taylor County, WI, Trempealeau County, WI

The radar

The La Crosse radar (KARX), 64 km from the middle of the area, began a volume at 19:53 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 12:00Z, 7.9 hours before the alert went out and 160 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: 989 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 58 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 La Crosse, WI wrote its last area forecast discussion before this dense fog advisory went out at Feb 2, 11:57 AM CST, 1 hour 55 minutes earlier.

Area forecast discussion, Feb 2, 11:57 AM CST, 1 hour 55 minutes before

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Hazardous weather outlook, Feb 2, 10:26 AM CST, 3 hours 26 minutes before

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In the hours before

Special weather statement, Feb 2, 12:33 PM CST, 1 hour 19 minutes before

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The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 1, 7:37 PM CST	Dense Fog Advisory	ARX	Adams, Buffalo, Clark, Crawford, Grant, Jackson and 7 more	40 hr

Nearby

Dense Fog Advisories in Minnesota, 2012 Dense Fog Advisories in Wisconsin, 2012 Dense Fog Advisories in Iowa, 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.