Alert archive / South Dakota / Winter Weather Advisories in 2012

Winter Weather Advisory 8, NWS Sioux Falls, SD

February 22, 201212 counties in South Dakota; 4 counties in Iowa; 6 counties in Minnesota

NWS Sioux Falls, SD issued this winter weather advisory at Feb 22, 2012, 10:39 PM CST for 12 counties in South Dakota; 4 counties in Iowa; 6 counties in Minnesota. It took effect at Feb 23, 2012, 3:00 AM CST. It was in force for 18 hr.

The area

The counties it named.

The facts

Issued
Feb 22, 2012, 10:39 PM CST (04:39 UTC)
In effect from
Feb 23, 2012, 3:00 AM CST
Expired
Feb 23, 2012, 9:00 PM CST
In force
18 hr
Issued by
NWS Sioux Falls, SD
All 22 counties

Dickinson County, IA, Ida County, IA, Plymouth County, IA, Woodbury County, IA, Cottonwood County, MN, Jackson County, MN, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brule County, SD, Clay County, SD, Douglas County, SD, Hutchinson County, SD, Kingsbury County, SD, Lake County, SD, Moody County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 13 km from the middle of the area, began a volume at 04:37 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

Aberdeen, SD (KABR), launched 00:00Z, 4.7 hours before the alert went out and 203 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-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 2012-02-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Aberdeen, SD at 00:00Z on 2012-02-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
1541 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

Nearby

Winter Weather Advisories in South Dakota, 2012Winter Weather Advisories in Minnesota, 2012Winter Weather Advisories in Iowa, 2012Every winter weather 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.