Alert archive / South Dakota / Winter Weather Advisories in 2018

Winter Weather Advisory 2, NWS Sioux Falls, SD

January 21, 201812 counties in South Dakota; Lincoln County, Lyon County, Pipestone County, Minnesota

NWS Sioux Falls, SD issued this winter weather advisory at Jan 21, 2018, 3:41 AM CST for 12 counties in South Dakota; Lincoln County, Lyon County, Pipestone County, Minnesota. It took effect at Jan 21, 2018, 6:00 AM CST. It was in force for 36 hr.

The area

The counties it named.

The facts

Issued
Jan 21, 2018, 3:41 AM CST (09:41 UTC)
In effect from
Jan 21, 2018, 6:00 AM CST
Expired
Jan 22, 2018, 6:00 PM CST
In force
36 hr
Issued by
NWS Sioux Falls, SD

Counties Lincoln County, MN, Lyon County, MN, Pipestone County, MN, Aurora County, SD, Brookings County, SD, Brule County, SD, Davison County, SD, Hanson County, SD, Jerauld County, SD, Lake County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD

The radar

The Sioux Falls radar (KFSD), 69 km from the middle of the area, began a volume at 09:42 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

Omaha, NE (KOAX), launched 00:00Z, 9.7 hours before the alert went out and 306 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, Omaha, NE at 00:00Z on 2018-01-21Temperature 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, Omaha, NE at 00:00Z on 2018-01-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -2 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
1484 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
-2 m²/s²
0-3 km storm-relative helicity
235 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 21, 3:41 AM CSTBlizzard WarningFSDClay, Lincoln, Union, Yankton43 hr

Nearby

Winter Weather Advisories in South Dakota, 2018Winter Weather Advisories in Minnesota, 2018Every winter weather advisory in 2018

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.