The seasons first widespread major storm struck the state on the 11th, and continued into the early morning hours of the 12th.  A strong upper level system intensified over the central U.S. from the 10th into the 11th.  Surface low pressure developed to the west of Iowa, and moved east into northwest Iowa by the early morning of the 11th.  The low continued across the north half of Iowa on the 11th, reaching Lower Michigan by mid day on the 12th.  Initially, the storm was quite moisture starved.  As it intensified, the dynamics of the storm strengthened the inflow, feeding the storm system.  The presentation on satellite imagery was classic by the morning of the 11th with a clear dry slot and deformation zone present.  The dry slot punched into southwest and central Iowa with a line of showers and isolated thunderstorms firing up on the leading edge of the dry slot.  Cold air rushed in on the back side of the storm.  The deformation zone curled around the back side of the low and produced moderate to occasionally heavy snow.  Temperatures plummeted as strong northwest winds swept across the state.  Blizzard conditions developed as winds increased to sustained winds of 30 to 45 MPH, with gusts to near 70 MPH at times.   Some of the higher gusts included a 71 MPH gust in Audubon, 65 MPH gust at Farnhamville and on the mile long bridge across Saylorville Reservoir, 64 MPH at Adair and Boone, 63 MPH at Carroll, 61 MPH at Creston, 60 MPH at Algona, and 59 MPH at Ankeny and Windsor Heights.  The winds caused whiteout conditions over western Iowa by the mid afternoon hours.  Boone County declared a Civil Emergency as travel became impossible in the county.  Nearly all roads were closed in the northwest quarter of the state, with travel not recommended over nearly all of the Des Moines CWA.  Interstate 80 was closed for several hours from the Nebraska border to just west of Des Moines.  Many of the counties across the northwest half of Iowa had to remove snowplows from the highways as it was to dangerous to continue until the high winds subsided.  There were scattered power outages with the storm, but numbers were on the order of a few thousand customers during the peak.  There was some freezing rain at the onset of the storm, fortunately the amounts were limited to a few hundredths of an inch at most so damage was limited.  Much of the state did not have snow on the ground at the beginning of the storm.  This limited the amount of blowing to some extent.  Measurement of the snow was difficult.  Most amounts were in the 4 to 6 inch range over the northern third and western third of the state, with 1 to 4 inch amounts common elsewhere.  A narrow area of far northern Iowa reported 6 to 9 inches of snow for the 24 hour period.  There was a wide variance of measurements however.  As an example, a total of 4.4 inches was reported at the Des Moines airport, while an observer just 6 miles to the northwest only reported 0.6 inches.  Temperatures plummeted as well.  Readings that were in the 30s to mid 40s F in the early morning of the 11th, fell to the single digits and teens by the night of the 11th and early morning of the 12th.  Wind chill temperatures fell to -10 to -30 F across the area as well.

Blizzard in GUTHRIE, IOWA
From 11-DEC-10 13:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in DALLAS, IOWA
From 11-DEC-10 16:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in CASS, IOWA
From 11-DEC-10 13:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in ADAIR, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in MADISON, IOWA
From 11-DEC-10 15:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in ADAMS, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in UNION, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in TAYLOR, IOWA
From 11-DEC-10 15:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in RINGGOLD, IOWA
From 11-DEC-10 16:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in WINNEBAGO, IOWA
From 11-DEC-10 14:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in WORTH, IOWA
From 11-DEC-10 14:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in HANCOCK, IOWA
From 11-DEC-10 14:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in CERRO GORDO, IOWA
From 11-DEC-10 14:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in WRIGHT, IOWA
From 11-DEC-10 14:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in FRANKLIN, IOWA
From 11-DEC-10 15:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in HAMILTON, IOWA
From 11-DEC-10 16:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in HARDIN, IOWA
From 11-DEC-10 17:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in STORY, IOWA
From 11-DEC-10 18:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in EMMET, IOWA
From 11-DEC-10 09:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in KOSSUTH, IOWA
From 11-DEC-10 12:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in PALO ALTO, IOWA
From 11-DEC-10 12:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in POCAHONTAS, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in HUMBOLDT, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in SAC, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in CALHOUN, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in WEBSTER, IOWA
From 11-DEC-10 15:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in CRAWFORD, IOWA
From 11-DEC-10 12:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in CARROLL, IOWA
From 11-DEC-10 14:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in GREENE, IOWA
From 11-DEC-10 15:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in BOONE, IOWA
From 11-DEC-10 17:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in AUDUBON, IOWA
From 11-DEC-10 12:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in POLK, IOWA
From 11-DEC-10 18:00:00 to 11-DEC-10 22:00:00 (CST-6)
Property damage: 150.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in BUTLER, IOWA
From 11-DEC-10 18:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in BREMER, IOWA
From 11-DEC-10 18:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in GRUNDY, IOWA
From 11-DEC-10 19:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in BLACK HAWK, IOWA
From 11-DEC-10 20:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in MARSHALL, IOWA
From 11-DEC-10 19:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in TAMA, IOWA
From 11-DEC-10 20:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in JASPER, IOWA
From 11-DEC-10 19:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in POWESHIEK, IOWA
From 11-DEC-10 21:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in MAHASKA, IOWA
From 11-DEC-10 22:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in MARION, IOWA
From 11-DEC-10 19:00:00 to 12-DEC-10 06:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Blizzard in WARREN, IOWA
From 11-DEC-10 18:00:00 to 12-DEC-10 02:00:00 (CST-6)
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Official NWS Observations