A cold airmass was in place over Iowa as arctic high pressure slipped east of the state during the early morning hours of the 27th.  A strong upper level shortwave lifted out of the southern Rockies, racing northeast at 50 kts, during the overnight hours of the 26th and early morning of the 27th.  Temperatures were below freezing over northeast Iowa at sunrise on the 27th.  The southwest part of the state was in the mid to upper 30s at that time.  Very dry air was in place initially with dewpoint temperatures in the teens.  Very warm air moved aloft with 850 mb temperatures of +2 to +5 C.  A large area of rain developed southwest of Iowa with the approach of the shortwave.  As the area moved northeast into Iowa the precipitation fell in the form of freezing rain.  Temperatures that were above freezing fell to freezing or below due to evaporational cooling with the rainfall.  Much of Iowa received at least one tenth of an inch of ice, with most of the east half of Iowa receiving two tenths of an inch or more.  The heaviest ice accumulation was over the northeast part of the Des Moines CWA, roughly north of U.S. Highway 30 and along and east of the I-35 corridor.  These areas received general ice accumulations of one quarter to one third of an inch with spotty half inch amounts north of the Mason City area into Worth and Winnebago Counties.  Roads became treacherous with the freezing rain with numerous accidents reported.  In addition, walking became very dangerous.  In the Des Moines metro area there were at least 35 people treated for injuries caused by falling on the ice.  Tree and power line damage was limited due to the light winds during the event.  Several hundred homes lost power over the far northeast part of the CWA, with only very spotty outages elsewhere.  It was fortunate that the ice storm occurred on a non-business day.  Though there were many events cancelled, the impact was reduced since it was on a Sunday.

Ice Storm in STORY, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in MARSHALL, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in WINNEBAGO, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in TAMA, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in BUTLER, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in BREMER, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in WORTH, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in CERRO GORDO, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in HARDIN, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in WRIGHT, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in GRUNDY, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in FRANKLIN, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in BLACK HAWK, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ice Storm in HANCOCK, IOWA
From 27-JAN-13 06:00:00 to 27-JAN-13 19:00:00 (CST-6)
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter