Temperature and Precipitation Anomalies. The Midwest had a typical precipitation total for the region in July, ranking 47th wettest on record. However, it was not uniformly distributed, but fell mostly in Minnesota, eastern Iowa, and northern Wisconsin and Michigan. Bands in these areas received 5-10 inches of rain during the month (Figure 1). Along the Ohio River axis, conditions were much drier, receiving less than 50% of normal rain (Figure 2). Some areas of the southern Great Lakes and in the western Midwest were also similarly dry. While Minnesota had its 10th wettest July in 108 years, Ohio had its 14th driest. To compound matters in the dry areas, temperatures were well above normal throughout the Midwest, which had its 10th warmest July on record. No state ranked less than 25th warmest for the month. The temperature departures ranged from just 1-2°F in southern Missouri to 4-6°F in northern Michigan, with most of the Midwest being 2-4°F above normal (Figure 3). The dry areas during July continued a pattern started in June, and so developed abnormally dry to moderate drought states by the end of the month (Figure 4, National Drought Mitigation Center - NDMC), impacting substantially crop health. Hot and dry conditions coincided with the corn fertilization season over much of the Corn Belt, causing substantial losses in yield potential for the season.

Extreme Events and Impacts.

July 10, 2002: Lake Erie Tragedy Belies Relatively Calm Severe Weather Season.
Four weather-related fatalities occurred on the shore of Lake Erie on July 10, when a strong north wind caused an especially high wave action and dangerous rip tide at Nickel Plate Beach, Huron, OH. Four swimmers attempting to rescue a fifth person drowned, while the person who was originally caught by the rip tide survived. The beach had been closed to swimming due to the strong winds and dangerous surf. There was also some severe weather on July 9 and 10 as a cold front moved across the region from north to south. On the evening of the 9th, severe thunderstorms near Indianapolis caused a multiple-semi truck pile-up on I-65, causing 1 death. A very strong squall line swept through central Iowa the following morning (Figure 36, NWS), causing numerous traffic accidents and small power outages. The severe weather season as a whole, though, has been very mild in the Midwest this year. For the U.S., there have been 60% reductions in both numbers of tornadoes and numbers of killer tornadoes compared to the last 3 years. Unfortunately, 6 of the 11 recorded U.S. tornado deaths have occurred in the Midwest: 4 in Illinois, and 1 each in Missouri and Kentucky. The total of 6 to date is quite a bit less than the Midwest region average of 29 tornado deaths per year established between 1950 and 1994. The year 1986 holds the record for the smallest number of tornado deaths in the U.S. with 15, and this could be challenged this year.

July 15-23, 2002: Dryness and Increasing Impacts.
While the severe weather was not welcomed in Detroit, the accompanying rain was appreciated, given the burgeoning drought in the area of southern Michigan and northern Ohio. Most counties in southeastern Michigan continue to be under water use restrictions due to a lack of water pressure at the periphery of the system. Outdoor use of water was banned between 6 and 9 AM and 6 and 9 PM, the peak hours for water use inside residences. Across the Midwest, rain was appreciated by farmers, especially those in the narrow zones between "not enough"; and "flash flooding". Prior to the rain on July 21-23, USDA agricultural surveys on July 21 indicated tremendous percentages of the farmland in the Midwest were short or very short of topsoil moisture: Ohio 83%, Michigan 81%, Illinois 78%, Indiana 72%, Iowa 68%, Wisconsin 68%, Missouri 64%, Kentucky 47%, and Minnesota 31%. Significant corn yield losses are now assured in the Western Corn Belt in eastern Nebraska and southwestern Iowa, while the rains this week may have saved substantial yield potential where they fell. However, the Corn Belt locations that received rain this week are not out of the woods yet, and all areas will require more weeks like this one to even approach the 5-year yield normals. Those areas in the Corn Belt that missed significant rain during this period will likely face substantially reduced yield expectations even with a return to wetter conditions.

July 28-31, 2002: Multiple Severe Windstorms to End the Month.
Severe weather damage was widespread during the last four days of July. On the 28th, 10,000 homes and businesses lost power in eastern Iowa, flights were delayed at Minneapolis-St. Paul International Airport, 20,000 utility customers lost power in western and central Michigan, and flash flooding occurred in a number of counties in central Illinois. On the 29th, 17,000 customer lost power in the Indianapolis area and 24,000 residences lost power in Greater Cincinnati as the front continued to the east. Crop damage and downed trees were common in all these areas due to high winds. The most severe weather occurred on the 30th, marching through southern Minnesota, central Wisconsin, and north Lower Michigan. Several tornado sightings were reported in central Wisconsin, and straight-line wind gusts were measured in excess of 50 mph at several recording stations, and estimated to be 80 mph at other locations. Substantial trees were downed, including one at a Boy Scout camp near Oshkosh that fell on a tent and killed one scout and severely injured another. More than 20,000 lost power in Wisconsin, and some out buildings and homes were damaged. The line of thunderstorms then crossed Lake Michigan and brought winds measured at up to 77 mph to Traverse City and other locations in northern Lower Michigan. More than 14,000 homes were without power there. On the 31st, the action shifted further north, and two separate lines of storms raked the Minnesota Arrowhead and the Upper Peninsula of Michigan. The storms caused wind damage with 70 to 90 mph winds, knocking out power on the Keweenaw Peninsula for 10,000 customers. Heavy rain accompanying the storms caused flash flooding in many locales, and flooded the lower level of the Delta County Jail.