April 15-21, 2015
Midwest Weekly Highlights - April 15-21, 2015
Staying Warm
Above normal temperatures continued this week across the region (Figure 1), a trend that has stayed since the beginning of April (Figure 2). Most areas were 3-5°F above normal, while the eastern Ohio Valley was the relative hot spot at 5-7°F above normal. Overnight lows were quite mild during the period across the Ohio Valley, which aided in the well-above normal average temperatures. Despite the above normal temperatures averaged across the period, the well-below normal temperatures on April 21 will likely be the more remembered (Figure 3). Average temperatures were 10-15 degrees below normal across Minnesota and Wisconsin, while the rest of the region was in the single digits below normal.
April Showers Continue
Rain and some snowfall continued to bring ample precipitation to many parts of the Midwest this week (Figure 4). Kentucky and the Ohio Valley added even more precipitation to their spring total, where most of Kentucky is 6-10 inches above normal since March 1 (Figure 5). One to two inches of rainfall fell along the Wabash River Valley as well this week, which led to flood warnings in Lafayette, IN and south. Iowa also had a wet week as 1-2 inches of precipitation fell across most of the state, leading to above normal precipitation for the week(Figure 6). Despite the ample rainfall, few severe weather reports were seen across the region (Figure 7). The entire region wasn’t above normal this week, however. Slightly below normal conditions were seen across most of Missouri, Illinois and Ohio. Portions of Minnesota, Wisconsin and Michigan also saw below normal precipitation for the period.
Snow continues to fall in northern Minnesota & Wisconsin as well as in Michigan's Upper Penninsula (Figure 8), but most areas only accumulated an inch or less of snow. Snowfall this late in the season is not that uncommon in the far north, however, as 30-year averages show 0.5-2.0 inches of snow normally falls in the northern parts of the region over this 7-day period (Figure 9).
Flooding Continues
The western Ohio Valley can’t catch a break lately when it comes to excess precipitation. Flood warnings continued on the Ohio River from Evansville, IN and west with the Green River in Kentucky and Wabash River in Indiana also above flood stage. Waters should recede in the coming weeks as near normal precipitation is expected through the end of the month, with below normal precipitation expected for the first week of May (Figure 10).
Drought Holding Steady
Near normal precipitation kept drought conditions at the status quo this week across Minnesota and northern Wisconsin according to the latest Drought Monitor for the Midwest (Figure 11). Above normal precipitation in Iowa this week helped some areas that were abnormally dry. Unfortunately, below normal precipitation is expected to end the month in the upper Midwest (Figure 12), possibly worsening drought conditions.
Freeze Susceptibility Increasing
With southern areas of the Midwest now accumulating between 100-300 growing degree days since the last freeze this spring (Figure 12), the chances of damage to growing plants is increasing. Below normal temperatures are expected in the Midwest to end the month (Figure 14), which may cause crops, flowering trees and plants to be susceptible to freezing. To learn more on freeze susceptibility, including freeze maps and guidance, see the MRCC’s Vegetation Impact Program page.
-BJP-