A strong trough of low pressure in the upper atmosphere moved into the southwest U.S. late on the 17th and early on the 18th.  The system was very fast moving with a strong jet of 165 kts streaming up the east side of the trough.  A short wave ejected out of the trough and raced northeast through the central U.S., reaching Illinois by the morning of the 19th.  Low pressure at the surface formed over western Kansas during the afternoon of the 18th. It moved to northeast Kansas by evening, and to near Burlington, IA by sunrise on the 19th.  A strong low level jet pushed moisture over a polar airmass that was in place over Iowa.  In addition, the atmosphere became quite unstable for December over the state, resulting in the development of thunderstorms over a large part of Iowa during the overnight hours of the 18th into the 19th.  Temperatures over southern Iowa remained in the 20s through the event, though the cold layer was quite shallow.  Temperatures aloft rose well above freezing, thus most of the precipitation that fell came in the form of freezing rain.  The freezing rain turned to sleet and snow briefly before ending.  Heavy ice accumulations occurred over southern Iowa, especially the southwest and southeast parts of the DSM CWA.  Ice accrual reached one half inch over Davis County, and around 0.6 inches in Adams Counties for the heaviest amounts.  Most of the area received between 0.25 and 0.4 inches of ice.  Spotty power outages were reported, however much of the power problems were mitigated by efforts the previous summer with tree trimming by the power utilities. Roads became very icy with all roads 100% ice covered.  Nearly all schools and many activities were cancelled for the 19th due to the ice.

Ice Storm in UNION, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in RINGGOLD, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in DECATUR, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in CASS, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in ADAIR, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in CLARKE, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in ADAMS, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in DAVIS, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in TAYLOR, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in MAHASKA, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in WAPELLO, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in LUCAS, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in MADISON, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in APPANOOSE, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in WAYNE, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Ice Storm in MONROE, IOWA
From 18-DEC-08 18:30:00 to 19-DEC-08 06:00:00 (CST-6)
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement