May 2019
Monthly Overview - May 2019
Wet
May precipitation for the Midwest
(Figure 1) ranked as the 3rd wettest in history (since 1895). Totals were near or below average in the Ohio River Valley and the northern third of Minnesota but well above average elsewhere (Figure 2). Large parts of Iowa, Missouri, Illinois, and Upper Michigan received more than twice their normal rainfall. May was the 10th straight month with above-normal precipitation for the region. May precipitation in Missouri set a new record while Iowa and Illinois ranked among the top-5 wettest in their histories. Spring precipitation for the Midwest
(Figure 3) ranked as the 7th wettest while the 6-month (December to May) and 12-month (June to May) periods both set new records for the region. Every 12-month period since January to December 2018 has set a new record for the region. All nine Midwest states ranked among the top-10 wettest for both the 6-month(Figure 4) and 12-month
(Figure 5) periods ending in May.
A Mix of Warm and Cool
May temperatures ranged from below normal in the northwest to above normal in the southeast (Figure 6). Temperature departures of up to 5°F below normal in parts of Minnesota warmed to as much as 4°F above normal in the southeastern parts of Kentucky and Ohio. Spring temperatures in the Midwest
(Figure 7) had a similar pattern with departures from normal ranging from 4°F below normal in Minnesota to 2°F above normal in Kentucky.
Major Flooding
Flooding was both extensive and persistent throughout May in the Midwest (Figure 8). Major flooding along the Mississippi and Illinois rivers, as well as many tributaries, were problematic throughout May. The Quad Cities, which span the Mississippi River along the Iowa and Illinois border experienced record long major flooding that lasted more than 30 straight days. Heavy rains in mid-May had rivers that had begun to recede rising again to major flood stages. Major flooding on the Mississippi stretched from the Quad Cities to St. Louis as May came to a close
(Figure 9).
Drought Stays Away
The lack of drought in the region continued through May. The entire year, January to May has been drought free in the Midwest. The string of 22 straight weeks extended the record without drought (US Drought Monitor began in 2000). The abundant moisture in the region this spring had even wiped out all areas of abnormally dry in the US Drought Monitor. The string of 12 straight weeks ended with a small area of abnormally dry emerging in northwestern Minnesota in the third week of May (Figure 10). Outside of this 12-week stretch, there were only two other weeks since the Drought Monitor began in 2000 with no abnormally dry areas in the Midwest.
Severe Weather Ramps Up
May saw widespread severe weather in the Midwest
(Figure 11). With well over a thousand reports of severe weather, including a string of days from the 14th to the 29th with at least a dozen reports each day. The reports peaked on the 22nd with more than 300 reports. Only five days, all early in the month had no reports of severe weather. Tornadoes were reported don 13 days in May across seven of the nine states, sparing only Kentucky and Wisconsin. Particularly hard hit were Missouri on the 21st and 22nd, Iowa, Illinois, Indiana, and Ohio on the 27th, and Iowa on the 29th.
Winter Hangs on in North
Winter kept a hold in the upper Midwest into May with both freezing temperatures and snow. Freezing temperatures (Figure 12) were reported in northern areas of Minnesota, Wisconsin, and Michigan throughout the first three weeks of May and then again in northeastern Minnesota on the 28th. Snow fell in the same northern areas on the 1st-2nd, 9th, and 20th-21st with Duluth setting a May record for a storm total snowfall of 10.9 inches on the 9th
(Figure 13).
Planting Delays Continue
Spring planting continues to be delayed by the wet weather in the region. As of June 2nd, corn planting trailed the 5-year average by more than 50% in Illinois, Indiana, and Ohio and trailed by more than 25% in Michigan, Missouri, and Wisconsin (Figure 14). Soybean planting also lagged by more than 50% in Illinois, Indiana, and Ohio with lags of more than 25% in Iowa, Michigan, Minnesota, Missouri, and Wisconsin
(Figure 15).
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