Midwest Weekly Highlights - October 1-7, 2012
Rain in Southern Midwest and Snow in the Upper Midwest
During the first week of October, parts of the southern Midwest received significant precipitation while a good portion of the upper Midwest did not receive any precipitation (Figure 1). A band of at least 1" of precipitation fell across the Ohio River Valley, with areas just north of the river receiving 1.5" to 2.5" of rainfall. This made for precipitation totals that were 150% to 300% above normal (Figure 2). Several daily precipitation records were set as a result of the significant precipitation in the southern Midwest. A large area encompassing southern Minnesota, Wisconsin, and northern Iowa did not receive any precipitation throughout the week.
Portions of the upper Midwest received their first measurable snowfall of the 2012-2013 season. During the middle of the week, from October 3rd through the 5th, several stations reported snowfall in northern Minnesota, northern Wisconsin, and Upper Michigan (Figure 3), producing totals that were a several inches above normal for this time of year (Figure 4). The heaviest snow during this early season snow event fell in Roseau County in Minnesota where there was just over 12" of snowfall reported. Snowfall totals in Wisconsin and Upper Michigan ranged from 0.1" to 2".
Below Normal and Widespread Freezing Temperatures
Cooler temperatures spread across the Midwest during the first week of October. Average temperatures were significantly below normal across much of the region, especially in the western Midwest where there were departures of 7°F to 10°F below normal (Figure 5). Further to the east, temperatures were closer to normal and in some locations in eastern Ohio and eastern Kentucky, slightly above normal. Even greater departures from normal are found when looking at maximum temperature (Figure 6). In Missouri, Illinois, western Kentucky, and portions of Indiana, maximum temperatures were 9°F to 13°F below normal.
In western Iowa, minimum temperatures were unusually low during the last couple days of the week for all but far eastern Iowa. Battle Creek, Iowa (Ida County) reported a low of 12°F on Saturday morning (Figure 7).
As a result of the cooler than normal temperatures during the first week of October, many stations in the southern Midwest reported their first 32°F freeze of the fall season (Figure 8). There were several first 28°F freezes reported as well across the central portion of the United States (Figure 9). Many stations reporting their first 32°F and 28°F freeze are at least one week ahead of the typical median date for first freeze (Figure 10). During the week, there were several daily temperature records set, many of which were record lows later in the week.
Producers took advantage of dry periods between rain events to continue harvest activities. Corn harvest is well ahead of the 5-year average in all nine states. The states with the most progress are Missouri, Kentucky, Illinois, and Wisconsin, with over 90% of the crop harvest in Missouri. Most states are running 30% to 40% ahead of the 5-year average. Soybean harvest ranges from 76% complete in Minnesota, which is 73% ahead of average, to under 20% complete in Missouri.