January 25-31, 2008
Midwest Weekly Highlights - January 25-31, 2008
Far From Quiet
The last week in January found the Midwest in the bulls eye of a very strong cold front, resulting in a very dramatic shift in temperatures within as little as a few hours. The week had average temperatures range from around 0°F in the far northwest of Minnesota to low 30°F readings along southern Missouri, Illinois and Kentucky (Figure 1). The warmest area was southwestern Missouri where temperatures hovered near 40°F. Missouri, west central Illinois and northern Michigan were the only locations to see temperatures above normal. Continued warm air surging ahead of a cold front helped to bring and keep temperatures well above normal to start the week. Cities like St. Louis Missouri saw record high temperatures in the 70's (Figure 2). Most of Missouri ranged from near normal to over 3°F above normal during the last week of January (Figure 3). Areas in Missouri, Iowa, Indiana, Ohio and Kentucky recorded temperatures ranging from 6°F below normal to around 2°F below.
A fair amount of the precipitation that fell through the week came as snow across the northern half of the region (Figure 4), while areas in Missouri, Iowa and Minnesota received little to no precipitation. The western areas of the region received as little as 0 to 10% of the normal for this time of year (Figure 5). Areas further east benefited from the passage of the cold front as over an inch of precipitation fell across the central area of the Bluegrass State, Indiana and Michigan (Figure 6). Drought conditions were unchanged across the Midwest during the final week of the month (Figure 7).
What Starts Well ... Ends ... Not So Well
The final week in January began with high pressure slowly drifting off towards the Atlantic. The backside of the high created southerly winds for most of the region. This allowed temperatures to reach incredible highs for this early in the year. St. Louis, Missouri reached 73°F on the afternoon of the 29th. That reading was not an all time high, but the temperature falls shortly following it were nearly a record breaking event. A strong arctic cold front swept across the area following the record temperatures. The front was accompanied by isolated thunderstorms over the region, snow and considerable blowing and drifting of the snow. The combination of rain, thunder, high winds, sleet, freezing rain, snow and blowing snow made travel extremely hazardous. It is not too often that a tornado watch and a blizzard/winter storm warning exist within a few counties of each other, but that in fact was the case on January 29 in the central Midwest (Watch/Warning Map).The snow and blowing snow produced white out conditions at times as winds gusted close to 50 mph. There has only been one other time (January 24th of 1943) in St. Louis that the temperature fell more than 58°F (all of the way down to 15°) in a matter of 24 hours (Figure 8). This event in 2008 tied for second with January 18th 1996 where temperatures fell from 65°F to 7°F. Areas around St. Louis saw the most dramatic drop in the Midwest - nearing a 60°F drop on that day . Many areas around the Midwest saw temperatures drop over 25°F in an hour (Figure 9) and there were even atmospheric pressure falls of over 7mb per hour. There were 4 reports of tornados in Illinois, Missouri and Indiana. Numerous trees fell as winds gusted as high as 81 MPH.
Many ice jams are occurring along Illinois rivers as an accumulation of ice restricts the flow of the river water. In early January, northern Illinois and northwest Indiana experienced heavy rainfall combined with warm temperatures that melted the existing snow causing near record flooding on some streams. Although water levels have receded since the near record levels, they remain above normal for this time of year. These higher than normal flows are resulting in more substantial flooding when an ice jam forms. The recent sub zero temperatures have increased the ice thickness. The worst ice jams are occurring near I-55 and on the Kankakee River.
Daily Records January 25 - 31
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