A powerful mid season winter storm moved northeast out of the four corners region of the United States and into the Northern Plains.  Ahead of this system, warm and moist air streamed northward creating widespread fog and freezing fog conditions during the days leading up to the event.  Heavy riming frost began to accumulate on power lines and tower guide wires, placing heavy strain on them by the time the freezing rain arrived in the late morning and afternoon hours on Friday, January 22nd.  Along with the freezing rain, southeast winds gusting over 30 mph also created a strain on sagging power lines.  Scattered power outages were reported as early as Tuesday, January 19th due to the frost covered lines, but the majority of power line and power pole damage occurred during the evening of the 22nd and the morning of the 23rd.  The freezing rain that arrived during the afternoon and evening of the 22nd was the proverbial ���straw that broke the camel���s back���.  By the time the rain, freezing rain, and snow ended Saturday morning, January 23rd, nearly every power cooperative across central and northeast South Dakota suffered extensive power pole and power line damage. Also, several radio and television towers were downed by the icing and strong winds.
The heavy icing and strong winds downed over 5000 power poles along with 21,000 miles of power lines across South Dakota leaving thousands of households without power.  Several homes sustained substantial damage caused by broken water pipes. Power was still not restored for many customers until several weeks after the event.  Power line crews from Minnesota, Kansas, and Oklahoma were called upon to help restore power.  Several counties, along with the state emergency operations center, opened emergency shelters for people to stay.  Forty-one National Guard members were on active duty across the state helping to restore power.  Many flights were delayed or cancelled at several airports.  The ice and the wind also helped topple a canopy at a truck stop at the intersection of Highway 20 and 212.  On January 23rd, a radio and television signal transmission tower northwest of South Shore was downed along with a tower north of Reliance and a radio tower southwest of Marvin.
The hardest hit area with this storm was the Cheyenne River and Standing Rock Sioux reservations in central and north central South Dakota.  With no electricity, residents were dependent on donations of food, bottled water, blankets, heat and light sources, toiletries, and cots.  The rural water system serving the Cheyenne River Sioux Tribe was shut down resulting in the state EOC shipping water to the reservation.
The Governor asked for a presidential disaster declaration for most of the counties and three reservations. The request was for both public and individual assistance for total damages estimated over 20 million dollars for the state.

Winter Storm in HAND, SOUTH DAKOTA
From 22-JAN-10 11:00:00 to 23-JAN-10 03:00:00 (CST-6)
Reported by: NWS Employee

National Weather Service Wessington weather radio tower had collapsed from frost and ice accumulation.

Winter Storm in FAULK, SOUTH DAKOTA
From 22-JAN-10 09:00:00 to 23-JAN-10 03:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in EDMUNDS, SOUTH DAKOTA
From 22-JAN-10 09:00:00 to 23-JAN-10 02:00:00 (CST-6)
Reported by: Emergency Manager

Winter Storm in MCPHERSON, SOUTH DAKOTA
From 22-JAN-10 09:00:00 to 23-JAN-10 02:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in MARSHALL, SOUTH DAKOTA
From 22-JAN-10 14:00:00 to 23-JAN-10 04:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in DAY, SOUTH DAKOTA
From 22-JAN-10 14:00:00 to 23-JAN-10 04:00:00 (CST-6)
Reported by: Emergency Manager

Winter Storm in CLARK, SOUTH DAKOTA
From 22-JAN-10 14:00:00 to 23-JAN-10 04:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in ROBERTS, SOUTH DAKOTA
From 22-JAN-10 15:00:00 to 23-JAN-10 05:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in GRANT, SOUTH DAKOTA
From 22-JAN-10 11:00:00 to 23-JAN-10 05:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in CODINGTON, SOUTH DAKOTA
From 22-JAN-10 13:00:00 to 23-JAN-10 05:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in HAMLIN, SOUTH DAKOTA
From 22-JAN-10 13:00:00 to 23-JAN-10 05:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in DEUEL, SOUTH DAKOTA
From 22-JAN-10 14:00:00 to 23-JAN-10 06:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in CORSON, SOUTH DAKOTA
From 22-JAN-10 00:15:00 to 22-JAN-10 20:00:00 (CST-6)
Reported by: Broadcast Media

Winter Storm in DEWEY, SOUTH DAKOTA
From 22-JAN-10 00:15:00 to 22-JAN-10 20:00:00 (CST-6)
Reported by: Newspaper

Winter Storm in CAMPBELL, SOUTH DAKOTA
From 22-JAN-10 08:00:00 to 22-JAN-10 22:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in WALWORTH, SOUTH DAKOTA
From 22-JAN-10 08:00:00 to 22-JAN-10 23:00:00 (CST-6)
Reported by: Emergency Manager

Winter Storm in POTTER, SOUTH DAKOTA
From 22-JAN-10 08:00:00 to 22-JAN-10 23:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in SULLY, SOUTH DAKOTA
From 22-JAN-10 10:00:00 to 23-JAN-10 01:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in HUGHES, SOUTH DAKOTA
From 22-JAN-10 10:00:00 to 23-JAN-10 01:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in LYMAN, SOUTH DAKOTA
From 22-JAN-10 10:00:00 to 22-JAN-10 23:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in BUFFALO, SOUTH DAKOTA
From 22-JAN-10 10:00:00 to 23-JAN-10 01:00:00 (CST-6)
Reported by: Utility Company

Winter Storm in HYDE, SOUTH DAKOTA
From 22-JAN-10 11:00:00 to 23-JAN-10 02:00:00 (CST-6)
Reported by: Utility Company