|
SEVERE
WEATHER FACT SHEET
   
There are a number of severe weather hazards that affect
Illinois, including thunderstorms, tornadoes, lightning,
floods and flash floods, damaging winds and large hail. Severe
weather hazards have the potential to cause
extensive property damage, injury and/or death.
Tornadoes
A tornado is a violent, rotating column of air extending from a
thunderstorm to the ground.
Most tornado damage paths are less than 100 yards wide and a couple of
miles long, but
can be up to a mile wide and 50 miles long.
Most tornadoes occur in the spring, but they have occurred every month of
the year.
In 2002, 35 tornadoes occurred in Illinois.
In 2003, a record setting 120 tornadoes occurred in Illinois,
resulting in two deaths, 81
injuries, and more than $40 million in damage. The previous
record was 107 set in 1974.
In 2004, 80 tornadoes occurred in Illinois, resulting in 9 deaths and 23
injuries.
There is an average of 39 tornadoes per year in Illinois.
Thunderstorms
Severe thunderstorms can produce tornadoes, damaging winds, lightning,
hail or heavy rain.
Thunderstorms are most likely to happen in the spring and summer.
In Illinois, severe thunderstorms frequently occur in the late afternoon
or evening.
Most lightning deaths occur in open fields, and under or near trees.
Ninety-six people have been killed by lightning in Illinois in the past 40
years.
In 2001, Illinois ranked second in the United States for lightning
fatalities.
In 2003, large hail resulted in nearly $20 million in property and crop
damage in Illinois.
The largest hailstone in 2004 was in McLean county, 8 miles north of
Bloomington/
Normal, near the town of Hudson where 4.25” hail fell on the
afternoon of July 13th.
Flooding
Flooding is the number one severe weather killer nationwide.
Nationally, 75 percent of the presidential disaster declarations
are the result of floods.
Floods can take several hours to days to develop.
The most dangerous type of flooding is a flash flood. Flash
floods can sweep
away everyone and everything in their path.
Most flash floods are caused by slow-moving thunderstorms, and occur most
frequently at night, in mid to late summer.
Fourteen people in Illinois have died from flash floods since
1995. Most of the deaths
occurred in vehicles |
