Climate
Illinois has a continental climate, with large temperature extremes not moderated by either mountains or oceans. Weather is influenced primarily by cold Canadian Arctic air in the winter, and warm, humid air from the Gulf of Mexico in the summer. High temperatures in the south of the state are about 10 to 12 °F. warmer than the north. Average annual temperature is 47 °F. in the north and 58 °F. in the south. Temperatures greater than 90 °F. occur about 45 days per year in the south, and 12 days per year in the north. Temperatures below zero °F. occur one day or less per year in the south, and 12 days per year in the north. Annual rainfall is 34 inches (860 mm) in the north and 46 inches (1,200 mm) in the south.
Prevailing winds are from the west. Average wind speeds "blowing off the prairie" are greater in the Chicago area. Statewide, the wind speeds average 8 to 12 miles per hour (13 to 19 km/h),and is greater in the winter than in summer.
Snowfall averages 30 inches (760 mm) in the north and 10 inches (250 mm) in the south, although the actual snowfalls vary greatly by year. In some years, southern Illinois receives very little snowfall, and may never get typical winter weather.
Most of the state has four distinct seasons. The southernmost part of the state is heavily forested and the trees are noted for having beautiful fall colors.
Tornadoes are a common hazard, primarily in the central part of the state, with peak months in June and April. Freezing rain is most common in central Illinois.
Read more about this topic: Geography Of Illinois
Famous quotes containing the word climate:
“When we consider how much climate contributes to the happiness of our condition, by the fine sensation it excites, and the productions it is the parent of, we have reason to value highly the accident of birth in such a one as that of Virginia.”
—Thomas Jefferson (1743–1826)
“Then climate is a great impediment to idle persons; we often resolve to give up the care of the weather, but still we regard the clouds and the rain.”
—Ralph Waldo Emerson (1803–1882)
“The climate has been described as “ten months winter and two months mighty late in the fall.””
—Administration in the State of Colo, U.S. public relief program (1935-1943)