Midwest Weekly Highlights - May 1 - 10, 2007

From too much to not enough...

The first part of May saw temperatures above normal across entire Midwest, with the southwest and central portions showing the greatest departures - up to 10 °F above normal. And the coolest areas, Michigan and Ohio, were still 1-4°F above average (Figure 1).

However, precipitation was the main story for this time period as the Midwest was a study in contrasts. The western states were slammed with heavy rainfall and flooding while a swath from Chicago to the Ohio valley only received a quarter of the expected rainfall (Figure 2). The drought impacted areas of northern Minnesota, Wisconsin and the Upper Peninsula of Michigan again missed in rains that occurred early in the month (Figure 3).

Wet & Wild

High pressure that seemed to be stationary off the Eastern U.S. for much of the week had a heavily influence the weather pattern (Figure 4).

As a result of the heavy rains, flooding has occurred in both Iowa and Missouri (Figure 8). While not reaching 1993 stage heights, the National Weather Service reports that this event will be in the top three. At least nine levees have broken and more than twenty have been overtopped, allowing floodwaters to ravage cities and agricultural areas.

With fields underwater, some corn yields may be in jeopardy this year as planting has been halted in the affected areas and there are concerns fields may not dry out in time. Iowa and Missouri both are 20 - 40% behind the 2002 - 2006 corn planting average. This is in contrast to the rest of the Midwest that made great strides in planting during the first part of May. Illinois, Indiana, Kentucky and Minnesota all are now at near-normal to normal - almost doubling the percentage of acreage planted in most locations during the past week.

Flooding is expected to continue through much of next week. Cities, such as St. Louis, are expected to see some flooding as the flood wave moves south along the Missouri and Mississippi Rivers (Figure 9).

Hot & Dry

'Red Flag' Warnings were issued across northeastern Minnesota this past week as warm, windy and dry conditions continued to keep conditions favorable for fires. Authorities noted these conditions as "Explosive" near the Gunflint Trails, which is north of Grand Marais (Figure 10), where mandatory evacuations were ordered. The fires have engulfed over 55,000 acres and fighting fire will be quite difficult as only 5% is currently contained. Over 450 personnel are battling the blaze that has caused close to 2 million dollars worth of damage according to the Minnesota Incident Command System.

Northeast Minnesota is still classified as D3, or in extreme drought, according to the U.S. Drought Monitor (Figure 3). Conditions have not improved over the area since early April. Conditions have also begun to deteriorate across Northern Wisconsin and the western sections of the Upper Peninsula. They were downgraded from D0 to D1, or abnormally dry to moderate drought in intensity. Conditions will not be improving much over the short term as precipitation did not form over the region and the outlooks call for continued warm and dry conditions.

MCP/SSS