The quality controlled Iowa COOP data for March 2014 has been uploaded to the IEM. These observations are kindly provided by Harry Hillaker, our state climatologist, who passes along these notes on the month:

General Summary. Temperatures averaged 29.3° or 6.6° below normal while precipitation totaled 0.83 inches or 1.32 inches less than normal. This ranks as the 22nd coldest and 11th driest March among 142 years of records. A colder March was recorded just last year while there has not been a drier March since 1994. Snowfall averaged 6.1 inches or 1.4 inches above normal to rank as the 52nd snowiest March among 127 years of records. As has been the case for most of the winter season eastern Iowa recorded the coldest/wettest weather while western Iowa was drier with more frequent reprieves from the cold.

Temperatures. The cold weather pattern that began in mid-October continued unabated through March as well. The first few days of the month were especially cold with temperatures averaging more than thirty degrees below normal on the 2nd and 3rd. Daytime high temperatures were below zero in many areas on the 1st and 2nd. Elkader and Decorah reported the month's lowest temperatures with -24° readings on the morning of the 3rd. Lower March temperature extremes have been recorded only three times (1948, 1960 and 1962) while the same -24° reading was last seen during the month on March 12, 1998. However there were no additional subzero temperatures after the 6th. Wind chill readings dipped as low as -37° at Mason City on the 2nd and -34° at Marshalltown on the 3rd. Only one day during the month (10th) averaged more than ten degrees warmer than normal. There have now been a total of only seven days since mid-October with temperatures averaging ten or more degrees above normal while 63 days in the period have been more than ten degrees below normal. Nevertheless, there were some sure signs of spring during the month. Temperatures reached into the 70's somewhere in Iowa on five days during the month with the first occurrence of the year coming on the 9th when Little Sioux reached 74°. The highest temperature was a 79° reading on the 31st at Clarinda and Shenandoah. Considerable frost remained in the ground at month's end across northern Iowa but soils finally thawed across most of southern Iowa over the last few days of March.

Precipitation. It was a rather dry month across Iowa. Only Tripoli and Decorah managed to exceed the normal precipitation for the month while Sidney experienced their driest March of record (0.04 inches, old record 0.07 in 1956 among 72 years of data). Glenwood and Shenandoah tied with 1956 for their lowest March precipitation totals. Monthly totals varied from 0.03 at Glenwood up to 2.21 inches at New Hampton. Snowfall totals varied from 0.3 inches at Hastings to 15.5 inches at New Hampton. The bulk of the month's precipitation fell in two events at opposite ends of March. Snow fell statewide on the 1st-2nd with three to five inches common from Spencer southeast to Keokuk with a maximum amount of 8 inches reported at Zearing in Story County. The other event on the 27th brought rain statewide (with a dusting of snow in the far northwest) with greatest amounts across the northeast with Coggon (Linn County) reporting 1.24 inches.

Heating Degree Day Totals. Home heating requirements, as estimated by heating degree day totals, averaged 2% less than last March but 22% more than normal. Degree day totals so far this heating season (since July 1, 2013) are running 14% greater than normal and last season's total. A colder heating season was last recorded 35 years ago.

Severe Weather. There were a handful of severe weather reports in south central Iowa on the afternoon of the 27th with a brief tornado reported near Chariton.

The following is the number of new daily records set at COOP sites based on data back to 1951.

                 2014_____________________2013___________________
                 MAR  FEB  JAN  DEC  NOV  OCT  SEP  AUG  JUL  JUN
Maximum High:     24   26   79   21   18   31  364  160   13   43
Minimum High:    406  306  219  141  170   60    9  102  204   97
Maximum Low:       7    7   22   14   25   46  213  183   58   50
Minimum Low:     439  379  194  177  241   70   32   96  217   53
Maximum Precip:   29   91   36   41  123  138   82   44   51  103

The following is some bulk statistics on how well IEM's daily COOP data estimator is performing on a monthly basis versus this QC'd dataset.

                 2014____________2013_________________________
                 MAR   FEB   JAN   DEC   NOV   OCT   SEP   AUG
High Temp Bias   1.3   1.4   0.8   0.7   1.1   0.2   0.2   0.2
High Temp RMSE   1.8   1.7   1.3   1.0   1.3   0.7   0.9   0.8
Low  Temp Bias   2.1   2.7   1.4   1.3   1.2   1.4   1.3   1.2
Low  Temp RMSE   2.4   2.9   1.6   1.6   1.5   1.7   1.8   1.6
Precip    Bias   0.36  0.31  0.49  0.24  0.09  0.18 -0.08  0.00
Precip    RMSE   0.46  0.56  0.59  0.31  0.28  0.59  0.46  0.50