December 1-10, 2006
Midwest Weekly Highlights - December 1-10, 2006
Winter Chill
Settles in Over Midwest
Much colder weather settled in over the Midwest in the wake of the
storm that raked the region November 30-December 1. Temperatures
averaged from 2°F below normal in eastern Ohio to 13°F below normal in
southwestern Missouri. (Figure 1).
The location of the coldest weather
mirrored the deep snow cover laid down by the storm of November
30-December 1 (Figure 2). Precipitation was much above normal across
the central portion of the region due to the storm at the start of the
week (Figure 3), but once the storm departed the region late on
December 1, precipitation this week was generally confined to
lake-effect snow areas as the cold air streamed over the still warm
waters of the lakes (Figure 4).
The heavy precipitation on November
30-December 1 provided relief to dry areas of the central Midwest, but
much of northern Minnesota into northwestern Wisconsin remained
entrenched in Extreme Drought as depicted in the December 5 U.S.
Drought
Monitor (Figure 5).
Storm Continues to Pound Region on December 1
Although the impact of the major winter storm was largely felt on November 30th, the storm affected much of the region east of the Mississippi River through December 1. Some of the heaviest snow fell during the early morning hours of December 1 from southeastern Wisconsin through western and central Illinois (Figure 6). Blizzard conditions occurred between about 6:00 a.m. and 11:00 a.m. CST within 3 to 5 miles of the Lake Michigan shoreline in the Wisconsin counties of Milwaukee, Racine, and Kenosha. Northerly winds gusted to 35 to 40 mph in this area, with visibilities reduced to zero to one quarter mile. Ahead of the cold front arcing out ahead of the low, strong to severe thunderstorms developed across Ohio and Kentucky. During the early morning hours scattered severe thunderstorms caused minor damage in far southeastern Indiana, and later in the day some tree and power line damage was reported in far eastern Kentucky and southeastern Ohio. In the wake of the cold front, strong winds gusting from 50 to 60 mph, produced by the intensifying storm center over the Great Lakes, caused some roof and tree damage and scattered power outages in some western Ohio counties.
Most of the snow was over in the lower Midwest by noon CST on December 1, while precipitation continued over southeastern Wisconsin and much of Michigan (Figure 7). By late in the afternoon of December 1 the storm center was departing northeast out of the Great Lakes (Figure 8) leaving a wide swath of snow and ice, and more than a half million customers without power in Missouri and Illinois.
Aftermath
The effects of this early winter storm were felt long after it departed the region. On the afternoon of December 1, Ameren Energy, which serves a large portion of eastern Missouri and central Illinois, reported more than a half million outages serving 2.4 million customers (Figure 9). Damage to power lines and trees was extensive. Repair crews were hampered by incredible accumulations of ice (Figure 10, Figure 11) and sub-freezing weather which prevented any of the ice from melting. Low temperatures on December 2 dropped to the single digits in southwestern Missouri (Figure 12), where Joplin reached a new record low of 6°F, breaking the old record of 7°F in 1985. Vichy-Rolla set a new record of 11°F, breaking the old record of 12°F set in 1979. On December 3 high temperatures were in the low to mid 30s in Missouri and only in the teens in Illinois, Iowa, Minnesota, and Wisconsin (Figure 13). Springfield, IL set a record low high temperature on December 3 of 17°F, breaking the old record of 18°F set in 1893. Peoria, IL reached only 17°F, tying the record low maximum set in 1929. On the morning of December 4 a number of new low temperature records were set or tied in Missouri and Illinois. Joplin, MO dropped to 10°F, breaking the old record of 13°F set in 1989. Vichy-Rolla, MO had a minimum temperature of 7°F, shattering the previous record of 14°F set in 1966. Four deaths were attributed to cold weather in Chicago, most elderly persons. The area enjoyed a brief warm-upon December 6 when temperatures finally managed to climb above freezing (Figure 14). Ameren Energy still reported more than 96,000 outages on that day (Figure 15). By late on December 8 most of those affected by the storm had power restored (Figure 16).
In
addition to the snow and ice, flooding was observed on rivers in Ohio,
Indiana, and Illinois from the heavy rain that preceded the snow. The
Illinois River at Havana reached 14.42 feet on December 8,
0.42 feet above flood stage.
Lake Snow Machine Switched to "High"
December 7 winter storm warnings were issued for counties in
northeastern Indiana and counties along the western shore of lower
Michigan for lake effect snow as far north as Cadillac (Wexford
County), and lake effect snow occurred all the way
up to
Traverse City, MI. Snow and winds gusting to 25 to 30 mph along and
near the Lake Michigan shoreline counties produced blowing and drifting
snow that made travel difficult to impossible through much of
the day. The National Weather Service reported an estimated
21 inches of snow in Bloomingdale, MI and 20 inches Grand Junction, MI
(both in Van
Buren County). Fennville (Allegan
County) also reported 20
inches of snow. Twelve to 15 inches of snow were reported at a number
of other locations in Van
Buren and Ottawa Counties.
Lake-effect snow warnings were also in effect for northeastern Ohio counties of Ashtabula, Cuyahoga, Geauga, Lake, Medina, Portage, Summit and Trumbull late December 7 into the morning of December 8. By the late evening of December 7, 5 to 9 inches of snow had piled up in some areas.
Last Shot of Cold Air...For Now
The lake-effect snow accompanied the last blast of Arctic air to sweep over the Midwest this period (Figure 17). Daytime temperatures on December 7 were only in the teens to mid 20s as far south as the Ohio River. However, by December 9 the center of the large cold high had moved to the southeast U.S., and southwesterly surface winds picked up over the region. High temperatures on December 9 reached the mid 50s from southwestern Missouri north to southwestern Minnesota, and the upper 30s to mid 40s over the remainder of the Midwest.
SDH