General Summary. Temperatures averaged 26.0° or 6.6°above normal while precipitation totaled 0.63 inch or 0.29 inch less than normal. This ranks as the 17th warmest and 34th driest January among 140 years of records. This was the warmest January since 2006 and driest since 2003.
Temperatures. Mild weather was the rule for most of the month as below normal temperatures were confined to only nine days (2nd, 12th-14th and 17th-21st). Daily maximum temperatures of 59° or higher (5th, 6th, 10th, 16th, 30th and 31st) were equally frequent as minimum temperatures below zero (13th, 14th, 18th-21st). Daily high maximum temperature records were equaled or exceeded on six dates (4th, 5th, 6th, 10th, 11th and 30th). The month’s highest temperatures were 68° readings at Sioux City on the 5th and at Shenandoah on the 30th. The frequent high temperatures were in major contrast to last January when no location in the state exceeded 45° during the month. The persistent warmth resulted in dangerously thin ice cover on lakes and ponds with at least three drownings from people falling through the ice reported late in the month. On the other extreme Elkader and Spencer reported low temperatures of -21° on the morning of the 21st. Estherville reported the lowest wind chill value at -30° on the morning of the 19th.
Heating Degree Days. Home heating requirements, as estimated by heating degree day totals, averaged 23% less than last January and 15% less than normal. Degree day totals thus far this heating season (since July 1, 2011) have averaged 16% less than one year ago and 14% less than normal.
Precipitation. January 2012’s monthly statewide average precipitation total was the lowest for any calendar month since November 2007. Only a few northern Iowa locations exceeded normal for the month. Preliminary totals varied from 0.10 inch at Guthrie Center and Osceola to 1.59 inches at Lansing. Snow was more substantial than in previous months this winter, but still less than normal in most areas. The exception was in northeastern Iowa where some locations received nearly double the usual January snow amounts with Guttenberg reporting the most with 17.5 inches. However, totals were far below normal in the southwest where Logan recorded only 0.6 inch of snow. The largest snow event of the month came on the 20th when amounts of four to seven inches fell over most of the northeast one-half of Iowa. Much of the eastern one-third of the state also saw 3 to 5 inches of snow on the 11th-12th. A statewide average of 6.6 inches of snow fell during the month which is 1.1 inches less than normal and ranks 56th lowest total among 125 years of records. At month’s end snow cover was restricted to northeast and extreme northern Iowa.
Winter Season. This winter season has been exceptionally mild in comparison to recent years, having followed five consecutive snowier than usual winters and four consecutive colder than normal ones. The statewide average snow fall total through the end of January has been 10.0 inches or 9.1 inches less than normal for this point in the season. This ranks as the 19th lowest season-to-date total among 125 years of records (lowest total in 9 years). Temperatures since December 1 have averaged 27.9° or 6.7° above normal. This ranks as the 8th warmest December-January period among 139 years of records (warmest in 10 years).
Harry Hillaker, State Climatologist
Iowa Dept. of Agriculture & Land Stewardship
Wallace State Office Bldg.; Des Moines, IA 50319
Phone: (515) 281-8981 |
