February 15-21, 2005
Midwest Weekly Highlights - February 15-21, 2005
Winter Weather Follows Hints of Spring
The week of February 15-21 started with a warm
and stormy period and ended with cold and snowy
conditions. A substantial amount of rain fell
early in the week as far north as southern
Michigan, while snow dominated the last days of
the period. The wettest area was split between
southern Michigan and southern Kentucky, both of
which had received 1-1.5 inches of rain (Figure 1). Another swath of 0.5 to 1.0 inches of
precipitation is visible from southeastern
Minnesota to central Michigan, where
precipitation exceeded normal over a wide area (Figure 2). In contrast, the west-central and
southwestern Midwest were much drier than normal
for the week. The Minnesota-Michigan
precipitation swath is largely due to a major
winter storm that dumped 6-12 inches in this
area on the 20th and 21st (Figure 3). The week
ended with an influx of cooler than normal air.
Combined with warm conditions in the southern
portion of the region during the beginning of
the week, the northern half of the Midwest was
cooler than normal, and the southern half warmer (Figure 4). Having had record warmth on the
15th, southern Missouri ended up 4-8°F above
normal for the week, while northern Minnesota
was 8-14°F colder than normal.
Warm and Wet Start to Week
A series of two cold fronts entered the region
from Canada starting early on the 15th. By
midday, a low pressure center along the first
front had entered Missouri, providing a strong
southerly flow ahead of the frontal boundary.
Daily maximum temperatures reach the low to mid-70s in southern Missouri, Illinois, and Kentucky
(Figure 5, Unisys). High temperature records of
75°F and 73°F were set in Missouri at the West
Plains and Vichy-Rolla airports, respectively.
However, the precipitation skipped most of
Missouri and formed ahead of the low,
concentrating especially in southern Michigan
(Figure 6, University Corporation for
Atmospheric Research - UCAR). Interestingly,
two separate lines of weak thunderstorms formed
in central Illinois, providing a pair of
thundershower opportunities to eastern Illinois
and western Indiana. After the second cold
front passed a day later, temperatures plunged
to below seasonal norms.
Snow Returns
In addition to lake effect snow after the early week events, another cold front barreled into the region from Canada on the 19th, bringing some light snow (less than a few inches) to Iowa, Wisconsin, and Illinois (Figure 7, UCAR), and reinforcing the cold air in place. On the 20th, a strong low tracked into the region from Wyoming (Figure 8, College of DuPage). The storm was amply supplied with Pacific moisture, and drew more from the Gulf of Mexico as it crossed the region. Winter storm warnings were issued from Minnesota through Michigan (Figure 9, Storm Prediction Center). Moderate to heavy snow fell in the cold sector north of the low (Figure 10, UCAR). A wide swath received more than 6 inches of snow (Figure 11), while individual locations reported storm totals as high as 14 inches in central Michigan. Green Bay, WI, and Duluth and Rochester, MN, set new daily snow fall records for either the 20th or 21st of February. The storm at the end of the season strained many municipal snow removal budgets that were low on funds due to frequent snows in January. In the Detroit area alone, more than 75 weather-related accidents were reported, and 154 flights were cancelled. Many other accidents were reported in Michigan, including two weather-related fatalities. Hundreds of weather-related accidents were reported on the roads of southeastern Wisconsin, including two more fatalities. Waukesha County alone had 239 accident reports. However, the snow that fell in eastern Minnesota did not make up for a generally dry winter. The city of St. Paul, MN, declared only its second snow emergency of the season, but even with the 5-6 inches of snow from this storm, the Minneapolis-St. Paul area is still having its 15th least snowy winter since the 1890s. The week ahead is not looking very moist, and may also be marked by gradual warming in the Midwest.