A Look Back at 2007 in Central and Southeast Illinois
Season by Season Highlights:
Winter Season (December 1, 2006 through February 28, 2007):
Temperatures -- Meteorological winter started out unseasonably cold, as heavy snow cover helped push temperatures below zero early in the month of December. However, significantly warmer weather was noted during the second half of December, with 50s and even a few lower 60s occuring by the end of the month, and above normal temperatures prevailed for a good portion of January as well.
A cold snap began during the end of January, continuing into the first half of February. While the second half of February was milder, much of central and eastern Illinois saw average temperatures for the month running from 9 to 12 degrees below normal.
Weather -- The biggest weather story was a blizzard which struck central Illinois beginning late February 12, continuing through the 13th. Snowfall totals of 8 to 14 inches were widespread in areas along the I-72 corridor, with localized totals in excess of 15 inches. Winds on the 13th gusted from 40 to 55 mph, creating zero visibility due to blowing snow and closing down many roads.
By the end of the month, the town of Rankin, east of Rantoul, had measured 31.5 inches of snow. The normal total for an entire winter in this area is around 24 inches!
Rapidly warming temperatures at the end of February resulted in ice jams occurring on some area rivers.
A couple of ice storms affected the area during the period. The first one, on January 12-13, produced ice accumulations of a quarter to half inch, primarily west of a Galesburg to Taylorville line. An ice storm on February 24 produced over a quarter inch of ice across areas west of the Illinois River, and up to a tenth inch in areas as far southeast as I-72. The worst of this particular ice storm affected northwest Illinois, eastern Iowa, and northeast Missouri. where ice totals as high as 1 to 2 inches caused extensive damage to trees and power lines, resulting in major and long-lasting power outages.
Earlier in the winter, January was fairly wet across the area, especially along the I-70 corridor where totals averaged 4 to 6 inches. Hutsonville finished the month with 9.13 inches of precipitation, including 3.80 inches from the 13-15th, and 3.50 inches on the 21st.
Spring Season (March 1 through May 31):
Temperatures -- After a period of unseasonably mild weather at the end of March, an extended period of cold weather occurred across central and southeast Illinois during the first two weeks of April. Temperatures from the 6-9th averaged approximately 15 degrees below normal; Jacksonville reported a low of 16 degrees on the 8th, the coldest temperature observed in Illinois during April. Several hard freezes occurred during this period, causing considerable tree and plant damage in areas where the warm weather had triggered an early bloom. However, by May, temperatures were averaging 4 to 6 degrees above normal for the month.
Weather -- The first of only 6 tornado touchdowns in central and southeast Illinois during 2007 occurred on March 1, when an EF-0 tornado hit Elwin, southwest of Decatur.
Flooding developed along the Illinois River late in March, due to excessive rainfall upstream. This persisted through much of April, and even into the middle of May around Havana and Beardstown, locations that typically see flooding linger much longer than other areas. Beardstown crested nearly 7 feet above flood stage on April 3, and Havana about 6 feet above flood stage.
Summer Season (June 1 through August 31):
Temperatures -- June and July averaged near to slightly below normal temperature-wise. However, the "Dog Days of August" lived up to their name, as extensive heat and humidity occurred much of the month. Average temperatures across the area for the month were 6 to 8 degrees above normal. Springfield reported an average high temperature of 90 degrees during the month. The hottest day was on the 15th. Springfield's high of 99 degrees was the warmest of the year, continuing the string of sub-100 degree high temperatures (12 years and counting). However, many other areas of central and west central Illinois did reach triple digits, reaching as high as 104 degrees in Jacksonville and Winchester.
Weather -- The main severe weather event was on August 23, when a bow echo of strong to severe thunderstorms moved out of southeast Iowa, and across the northern quarter of Illinois. A microburst in Galesburg produced damage to approximately 500 trees, and numerous buildings, due to high winds estimated to be around 100 mph across eastern portions of the city. Seven people were injured in Galesburg as the storms passed. These storms continued for several hours, and caused extensive damage in the Chicago metropolitan area around rush hour.
Otherwise, the severe weather season remained fairly quiet, with only intermittant, minor severe weather episodes.
Flooding developed along the Illinois River in late August and continued into the first part of September, as runoff and flows from extremely heavy rainfall in northern Illinois (10 to 15 inches in August) made their way downstream. River levels rose 3 to 4 feet above flood stage by the end of August, with flooding subsiding by the second week of September.
Autumn Season (September 1 to November 30):
Temperatures -- Although September as a whole average above normal, some localized freezing conditions were noted on the 15th. Although Springfield was not one of these locations, their low of 35 degrees was the coldest on record for so early in the season. A significant warmup occurred by the 21st, with high temperatures across central and southeast Illinois 50 to 55 degrees warmer than the coldest night of the 15th.
Unseasonbly warm weather prevailed into early October, with high temperatures from the 5-7th in the 90 degree range. Temperatures were averaging 10 to 15 degrees above normal. Temperatures were above normal for 23 consecutive days, from September 17 to October 9. It wasn't until November 2 before there was a widespread, hard freeze across central and southeast Illinois.
Peoria observed its 9th warmest September on record, 6th warmest October on record, and tied for its 3rd warmest autumn on record. 90 degree highs were observed there as late as October 7.
Weather -- Dry weather intensified during the late summer across southeast Illinois, with severe drought conditions spreading across areas south of I-70. Moderate drought conditions pushed northward across portions of central Illinois as well, as far north as Macomb and Canton. Rainfall in Decatur was running in excess of 10 inches below normal between March 1 and the end of October. A wetter period that began during November and continuing into December helped to alleviate the worst of the drought conditions.
Although a severe weather outbreak on October 18 produced several funnel clouds, none of them were confirmed to have touched down. The year finished with only 6 tornadoes across central and southeast Illinois, compared to the 72 which occurred in 2006.
Winter Season to date (December 1-18):
Temperatures -- Cooler than normal conditions have overall prevailed so far this month. Areas from about I-70 southward have been closer to normal, as the winter storm tracks have largely been far enough north to keep that area in the milder weather. On the 14th, high temperatures reached into the 60s in southeast Illinois, while temperatures were below freezing northwest of the Illinois River.
Weather -- Significant winter storms affected central Illinois during consecutive weekends. On the 8-9th of December, an ice storm brought accumulations over a quarter inch in most areas north of I-72, with the highest totals of 1/2 to 3/4 inches in Morgan and Cass Counties. Extensive tree damage occurred in some areas due to the excessive ice. The following weekend (15-16th), heavy snowfall of 6 to 9 inches was widespread roughly along the I-55 corridor eastward to near I-57.
Much of the lingering drought was alleviated when 1.5 to 3.5 inches of precipitation fell during the first half of the month.
Preliminary statistics for the 35-county Lincoln NWS coverage area: