Broad warm advection developed early on December 29 as a strong trough aloft sheared northeast through the central and northern Plains.  A period of strong frontogenesis shifted northeast, accompanied by a deep dendritic layer which produced snowfall rates up to an inch per hour.

Winter Storm in DOUGLAS, SOUTH DAKOTA
From 29-DEC-20 05:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: CoCoRaHS

Moderate to briefly heavy snowfall at times totaled 6.0 inches 5 miles west of Armour.

Winter Storm in BON HOMME, SOUTH DAKOTA
From 29-DEC-20 05:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Moderate to briefly heavy snowfall at times totaled 6.0 inches at Tyndall.

Winter Storm in YANKTON, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 15:00:00 (CST-6)
Reported by: Public

Moderate to briefly heavy snowfall at times totaled 6.0 inches 1 miles west southwest of Yankton.

Winter Weather in BRULE, SOUTH DAKOTA
From 29-DEC-20 04:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: CoCoRaHS

Snowfall totaled 4.3 inches at Chamberlain and 3.0 inches 2 miles south of Pukwana.

Winter Weather in AURORA, SOUTH DAKOTA
From 29-DEC-20 05:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 4.2 inches 4 miles southwest of Stickney and 2.8 inches at White Lake.

Winter Weather in DAVISON, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 15:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 5.0 inches at Mitchell.

Winter Weather in HUTCHINSON, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 15:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 5.5 inches at Menno and 5.0 inches at Parkston.

Winter Weather in CLAY, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 15:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 5.5 inches at Vermillion and 4.0 inches 6 miles southeast of Centerville.

Winter Weather in UNION, SOUTH DAKOTA
From 29-DEC-20 07:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: CoCoRaHS

Snowfall totaled 5.0 inches 6 miles north northeast of Elk Point and 4.5 inches in North Sioux City.

Winter Weather in LINCOLN, SOUTH DAKOTA
From 29-DEC-20 08:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 4.0 inches at Canton and 3.9 inches 1 mile north northeast of Harrisburg.

Winter Weather in TURNER, SOUTH DAKOTA
From 29-DEC-20 07:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 5.0 inches at Marion, 4.5 inches at Hurley and 3.8 inches at Parker.

Winter Weather in MINNEHAHA, SOUTH DAKOTA
From 29-DEC-20 08:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: Official NWS Observations

Snowfall varied from 3.5 to 5.0 inches around the Sioux Falls area, and 4.0 inches at Colton.

Winter Weather in MCCOOK, SOUTH DAKOTA
From 29-DEC-20 07:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 5.0 inches at Bridgewater and 3.0 inches 6 miles northwest of Montrose and 5 miles northeast of Salem.

Winter Weather in HANSON, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 3.5 inches at Alexandria.

Winter Weather in SANBORN, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: CoCoRaHS

Snowfall totaled 5.3 inches at Woonsocket.

Winter Weather in KINGSBURY, SOUTH DAKOTA
From 29-DEC-20 07:00:00 to 29-DEC-20 17:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 4.0 inches at De Smet and 3.0 inches at Iroquois.

Winter Weather in BROOKINGS, SOUTH DAKOTA
From 29-DEC-20 09:00:00 to 29-DEC-20 17:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 3.1 inches at Brookings and 3.0 inches at White.

Winter Weather in MINER, SOUTH DAKOTA
From 29-DEC-20 07:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 4.3 inches at Howard.

Winter Weather in LAKE, SOUTH DAKOTA
From 29-DEC-20 08:00:00 to 29-DEC-20 15:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 3.6 inches 2 miles north of Chester and 3.3 inches at Madison.

Winter Weather in BEADLE, SOUTH DAKOTA
From 29-DEC-20 06:00:00 to 29-DEC-20 17:00:00 (CST-6)
Reported by: Official NWS Observations

Snowfall totaled 3.0 inches at Huron.

Winter Storm in CHARLES MIX, SOUTH DAKOTA
From 29-DEC-20 04:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: CoCoRaHS

Moderate to briefly heavy snowfall at times totaled 6.0 inches 2 miles north of Lake Andes and 4.5 inches at Platte.

Winter Weather in JERAULD, SOUTH DAKOTA
From 29-DEC-20 05:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 4.0 inches at Wessington Springs.

Winter Weather in MOODY, SOUTH DAKOTA
From 29-DEC-20 08:00:00 to 29-DEC-20 16:00:00 (CST-6)
Reported by: COOP Observer

Snowfall totaled 4.9 inches at Flandreau.

Winter Storm in GREGORY, SOUTH DAKOTA
From 29-DEC-20 03:00:00 to 29-DEC-20 17:00:00 (CST-6)
Reported by: COOP Observer

Moderate to briefly heavy snowfall at times totaled 6.8 inches 4 miles south southwest of Pickstown, 6.5 inches 11 miles south southeast of Burke and 6.0 inches at Gregory.