June 24-30, 2006
Midwest Weekly Highlights - June 24-30, 2006
Cool End to June
Temperatures were near to below normal across the
entire Midwest the last week of June (Figure 1).
Temperatures averaged from 3°F to 5°F below
normal across
the central portion of the region, and were near to slightly above
normal only along the far northern fringes of the Midwest
from
northwestern Minnesota across to northwestern Wisconsin and a small
portion of the eastern Michigan U.P. Much of the Midwest was dry this
week, with rainfall from 10 percent to 50 percent of normal (Figure 2).
Only northern Illinois, the southern two-thirds of Wisconsin, and
northern lower Michigan received normal to above normal rainfall.
Although thunderstorms occurred almost daily in the Midwest, coverage
was in general spotty and the significant rain did not fall where it
was needed most in western Missouri through central Iowa and across
northern Minnesota and Wisconsin. The June
27 U.S. Drought Monitor expanded the area of Moderate drought from the
previous week in Missouri and Iowa, and the Abnormally Dry area in
Minnesota and Wisconsin (Figure 3).
Severe Storms Dot the Region
A strong upper level trough of low pressure slowly crossed through the Midwest this week, providing the lifting motion and cold air aloft needed for thunderstorm development (Figure 4). Severe weather was reported somewhere in the Midwest on all but one day this week. Most of the severe weather reports were for large hail and damaging winds, although a few small tornadoes were also reported. On June 24 one or more waterspouts were observed on Lake Winnebago in Calumet County, WI. On that day 1.75 inch hail caused extensive crop damage in Murray and Lyon Counties, MN. Thunderstorms winds snapped the blade off of a wind turbine in Lincoln County, MN. Thunderstorms winds downed trees and power lines in Iowa and Wisconsin.
On June 25 a tornado was reported southwest of Lafayette, IN (Tippecanoe County), but as of this writing no damage reports were available. Thunderstorms over northern Illinois produced heavy rain, causing street flooding in some areas. Another tornado occurred in Minnesota on June 26, where it was reported to be sucking up water from Dead Lake (Otter Tail County). In Illinois on this date 1.00 inch to 1.25 inch hail caused crop damage in McLean and Richland Counties in Illinois, and 2.00 inch hail was observed in Logan County. On June 27 there were two reports of a tornado (possibly the same one) near Newport, MI (Monroe County). The tornado overturned a parked tractor-trailer truck but apparently caused no other damage. Hail piled up to as much as four inches deep near Cadillac, MI (Wexford County), with some hail stones the size of ping pong balls.
As the upper level trough began to move out of the region on June 28 the storms became more numerous across Indiana, Michigan, and Ohio (Figure 5). By June 29 the Midwest weather was dominated by a large high pressure area, and this was the only day without reported severe weather. As the high moved to the east and southerly flow brought warmer and more humid air back into the Midwest on June 30, severe storms occurred again in Minnesota. Iowa, Missouri, Illinois, and Indiana as the next cold front pushed into the Midwest from the Northern Plains.
SDH