March 2021 Weather Summary

General Summary

Temperatures averaged 42.3 degrees or 6.4 degrees above normal while precipitation totaled 2.65 inches, which is 0.50 inch above normal. March 2021 ties 1977 as the 12th warmest March in 149 years of statewide observational records. This was also the 34th wettest March on record. A warmer March last occurred in 2012 while a wetter one occurred just last year.

Temperatures

Unseasonably warm temperatures blanketed Iowa during March with positive departures of up to eight degrees reported in western Iowa. The remaining portions of the state observed monthly averages between two to six degrees.

March’s statewide average maximum temperature was 52.5 degrees, 6.3 degrees above normal while the average minimum temperature was 32.0 degrees, 6.4 degrees above normal. Desoto (Harrison County) reported the month’s high temperature of 78 degrees on the 29th, 21 degrees above average. Elkader (Clayton County) reported the month’s low temperature of 7 degrees on the 2nd, nine degrees below average.

Heating Degree Days

Home heating requirements, as estimated by heating degree day totals, averaged 6% less than last March and 19% less than normal. Heating degree day totals are running 3% more than last year at this time and 2% less than normal.

Precipitation

A majority of the state’s National Weather Service co-op stations reported near to slightly above average precipitation during the month. The wettest conditions were found across portions of southwestern Iowa with above normal totals of up to three inches.

Monthly precipitation (melted snow and sleet plus rain) totals ranged from 0.89” at Estherville Municipal Airport (Emmet County) to 5.61” at a gauge near Pacific Junction (Mills County). In terms of snowfall, a majority of the stations across Iowa reported below-average totals with a preliminary statewide average of 2.2 inches, 2.5 inches below normal tying 2019 as the 27th lowest March total in 134 years of snowfall records; 2020 saw less snow. Muscatine (Harrison County) measured the highest accumulation of 10.0”.

Severe Weather

Iowa experienced a relatively quiet month in terms of severe weather with only two days of severe weather reports. A strong low pressure center over the upper Midwest swung its attendant cold front through Iowa during the afternoon of the 10th. Stronger thunderstorms formed in south-central Iowa with a few severe- warned thunderstorms pushing into eastern Iowa; Osceola (Clarke County) reported hail up to an inch in diameter.  The second severe weather event was also produced by a strong low pressure system spinning into Iowa from Missouri on the 24th. A brief spin-up tornado was observed near Fort Madison (Lee County) that caused some tree and shed damage.

US Drought Monitor

Drought and abnormally dry conditions contracted across Iowa during March as above-average precipitation helped ease dryness. The initial drought depiction at the beginning of March showed 52% of the state covered in D0 (Abnormally Dry) to D3 (Extreme Drought) conditions; the largest share was D0, which covered the northeastern to southwestern one-third of Iowa. Extreme drought continued to cover around 3% of northwestern Iowa. Multiple large-scale weather systems moved through Iowa as the month progressed, gradually chipping away at all categories. Much of southwestern Iowa saw a one-category improvement though in mid-March with a reduction of D1 (Moderate Drought) and D2 (Severe Drought) conditions on the southeast periphery of the existing northwest Iowa core by the end of the month. As of the last week of March, D0-D3 conditions covered 41% of Iowa, the lowest extent since June 30, 2020

Justin Glisan, Ph.D.
State Climatologist of Iowa
Iowa Dept. of Agriculture & Land Stewardship
Wallace State Office Bldg.
Des Moines, IA 50319
Telephone: (515) 281-8981
E-mail: Justin.Glisan@IowaAgriculture.gov


Weather By Districts

 
 
  TEMPERATURE (F) HEATING DEGREE DAYS PRECIPITATION (inches)
                      SNOWFALL
  March 2021 March 2021 Since Jul., 1, 2020 March 2021 Since Jan.1, 2021 Mar 2021
DISTRICT Average Departure* Average Departure* Average Departure* Average Departure* Average Departure* Average
                       
Northwest 40.2 +7.1 769 -196 6421 -263 2.23 +0.35 3.74 +0.55 5.5
North Central 40.0 +7.2 775 -201 6495 -239 2.09 +0.13 3.62 -0.03 5.9
Northeast 39.6 +5.5 787 -170 6478 -129 2.38 +0.41 4.25 +0.16 4.3
                       
West Central 42.9 +7.2 694 -189 5986 -200 3.24 +1.13 5.39 +1.68 1.8
Central 42.5 +6.6 706 -178 6074 -98 2.25 +0.06 4.04 -0.09 1.6
East Central 41.8 +4.5 719 -144 5996 -11 2.28 -0.00 4.60 -0.17 2.0
                       
Southwest 45.5 +7.1 616 -192 5621 -98 3.91 +1.68 6.10 +2.03 0.0
South Central 45.2 +7.0 625 -184 5636 -42 2.88 +0.59 5.25 +0.83 0.0
Southeast 44.6 +5.1 642 -155 5610 +36 2.91 +0.34 5.83 +0.43 0.0
                       
STATE 42.3 +6.4 711 -172 6059 -94 2.65 +0.50 4.68 +0.56 2.2
* Departures are computed from 1981-2010 normals.
The weather data in this report are based upon information collected by the U. S. Dept. of Commerce, NOAA National Weather Service.