April Temperatures Ranged from Below to Above Normal across Midwest
April temperature departures ranged from below-normal in the Great Lakes region to near- to above-normal elsewhere (Figure 1). Northwest Minnesota and northern Michigan saw monthly temperatures that were 3-5°F below normal, while southwest Missouri was 3-4°F above normal. A majority of the region was within 2°F of normal April temperatures.
The monthly departures resulted from highly variable temperatures throughout the month. The first half of April was unseasonably cold for a majority of the Midwest (Figure 2). However, the second half of the month was a mix of significantly above-normal temperatures across the region during the third week
(Figure 3) and a strong contrast between departures in the lower and upper Midwest at the end of the month (Figure 4). The range in April temperatures can be seen in the daily temperature records, with a majority of the record low temperatures falling during the first half of the month and the opposite for record highs
April Precipitation Varied and Above-Normal Snowfall in Upper Midwest
Above-normal precipitation fell across the western and northern portions of the region, with near- to below-normal precipitation elsewhere (Figure 6). Monthly precipitation totals ranged from as little as half an inch in southern Wisconsin to as much as 6-8 inches in northwest Missouri (Figure 7). A majority of the region received at least 2.5 inches of precipitation, and the statewide values were within 0.5 inches of normal April precipitation.
Due to unseasonably cold temperatures the first half of the month, some of the precipitation fell as snowfall in the Upper Midwest (Figure 8). Measurable snow (greater than or equal to 0.1 inch) fell as far south as southern Ohio, with the highest monthly snowfall accumulation of 20 to 25 inches in the Upper Peninsula of Michigan. Much of the Upper Midwest snowfall occurred during the first week of April, but the second week saw some snowfall as well, particularly in northern Ohio. The amount of snow falling in early April was above normal for this time of year for most places
(Figure 9). Portions of northern Michigan were 10 to 17.5 inches above normal, while the snow in northern Ohio was 2.5 to 7.5 inches above normal.
14-Week Drought-Free Streak Ended in April
After a 14-week stretch of drought-free conditions, moderate drought was reintroduced into the region in mid-April. As of the April 26th Drought Monitor, 2.28% of the region was experiencing moderate drought (D1), while 18.06% was considered abnormally dry (D0) (Figure 10). The 14-week stretch with no Midwest drought was the longest such period in the history of the U.S. Drought Monitor, which began in 2000. The lack of drought was good for the region heading into the growing season.
Midwest Crop Planting Progress
The warmer conditions the second half of the month, and near- to below-normal precipitation in many places, proved favorable for planting corn and soybeans in many states across the Midwest in April. Corn planting was first reported in Missouri, Kentucky, and Illinois on the April 11th USDA Crop Progress report. As of May 1st, all nine Midwest states reported corn planted with most above the 5-year average (Figure 11). Missouri had the highest percentage of 89% planted (42% above the 5-year average), while 60% of corn was reported planted in Illinois, Iowa, Kentucky, and Minnesota. Planting soybeans did not start in the region until late April, but all nine Midwest states as of May 1st had reported some soybeans (2-11%) planted.
Quiet Severe Weather Month
Based on climatology, the threat for severe weather increases in the Midwest as April progresses. April 2016 exhibited this pattern, with the final nine days of the month (April 22-30) having by far the most active severe weather days (Figure 12). There were only a few scattered severe weather reports in the three weeks prior. All nine Midwest states experienced some form of severe weather (i.e. hail, high wind, or tornado) during the April 22-30 time frame, with a majority of the reports concentrated in the southern-most states. Read more about the specific severe weather events in the Week 4 Midwest Climate Watch report.
Extension Climate Specialist for the MRCC and Illinois-Indiana Sea Grant.
The Iowa Climatology Bureau also contributed to this report.
The Missouri Climate Center also contributed to this report.