October 2005
Midwest Overview - October, 2005
A Very Warm Start, A
Cold End
A pattern of southwesterly flow aloft allowed summer-like weather to
continue through the first half of October with several days of warm
and unusually humid weather (Figure 1). Temperatures were
well above normal, with average daily temperature departures
as much as +8°F in northern Michigan (Figure 2).
However, it was clear that autumn and winter were not far
behind when a rapidly intensifying storm moved out of the Northern
Plains and into the northern Midwest the first week of the month.
The storm produced blizzard conditions in the Dakotas, snow
in northwestern Minnesota, and torrential rains in central Minnesota
and northwestern Wisconsin. The cooling behind the storm was
temporary, and mild conditions returned to the Midwest The weather pattern changed markedly the third week of
October as a trough of low pressure became established over the eastern
U.S. (Figure 3). This pattern produced northwest flow over
the Midwest, and the result was two weeks of colder than
normal weather. Temperatures the last two weeks of the month
ranged from 3°F to 4°F below normal in eastern portions
of the region to 2°F to 3°F above normal in
northwestern Minnesota (Figure 4). Temperatures for the month
were near normal across much of the Midwest, and 2°F to
3°F above normal from northern Wisconsin across the Michigan
Upper Peninsula and northern lower Michigan (Figure 5).
Extended periods of dry weather during the month allowed harvest
activities to proceed at full speed, and by the middle of October both
corn and soybean harvests were ahead of the 5-year averages in most
areas. Precipitation was well above normal across Minnesota
and Wisconsin, largely as a result of the storm the first week of the
month (Figure 6).
Precipitation was also above normal across
most of Ohio, and near normal across northern Missouri. The
remainder of the region received 50 percent or less of normal of normal
October rainfall, with southern lower Michigan the driest area with
less than 25 percent of normal precipitation. Detroit, MI
recorded only 0.13 inch of rain during October, making this the
driest October on record and the second driest month ever. The
previous record of 0.30 inch was established in 1892. The record
driest month in Detroit is February 1877 when only 0.04 inch of
precipitation was observed. Flint, MI received only 0.33 inch of
rain this
month, tying the record driest October (first set in 1944). A
cold front produced a large area of rain
across the southern half of the region on October 31, but those totals
are not reflected in the October statistics. (Note: The rain
that occurred on October 31 is reported on November 1). Moderate to
Severe drought conditions persisted in parts of Iowa, northern
Illinois, and southern Wisconsin. With the growing season now
over, drought impacts will be mostly hydrological.