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Tornadoes: Tornadoes in the Barren River Area
Tornado reports for the Barren River Area were collected from two
sources. The Historical Tornado Data Archive at the Storm
Prediction Center includes tornado reports from 1950 through 1995.
This source was supplemented by reports from the National Climatic
Data Center's Storm Data publication to identify more recent
tornadoes. A quality control procedure that included a review of
newspaper accounts was used in an effort to identify and correct
errors in the these sources.
Tornadoes are a well-publicized threat in the Barren River Area.
Still, the probability of any place within the 4,000 square-mile
region being struck by a tornado in a given year is small. During the
period 1950 through 2000, a total of 59 tornadoes were documented on 46
days. That is, the Barren River Area averages 1.2 tornadoes and 0.9
tornado days per year. The greatest number of tornadoes in a single
year was ten in 1997. Meanwhile 25 of the 51 years of record had no
tornado reports.
No place within the Barren River Area is safe from the threat of
tornadoes. Figure 12-1 shows the counties impacted by the 59 documented
tornadoes. Every county in the region has been struck at least once
over the past half century. As expected, the larger counties in the
region have been struck more frequently. Also, sparsely populated
areas typically have fewer reports since tornadoes that touch down,
particularly weak ones, are more likely to go undocumented.
Figure 12-1. Tornadoes and related casualties in the Barren River Area, 1950-2000.
Occurrences of tornadoes in the Barren River Area follow expected
patterns. They are most frequent in spring. The months of March,
April, and May account for 70 percent of the documented tornadoes
(Figure 12-2a). Also, most tornadoes occur in the afternoon or evening
hours (Figure 12-2b).
Figure 12-2. Tornadoes in the Barren River Area by month (a) and by time of day (b) follow expected patterns.
Fortunately, the majority of tornadoes to strike the Barren River Area
are relatively weak. The strength of a tornado is categorized
according to the Fujita scale (Table 12-1). Tornadoes in the F0 and F1
categories represent more than 60 percent of all documented tornadoes
in the region, yet they have not resulted in any fatalities (Table 12-2).
These tornadoes typically stay on the ground for only a short
distance, often less than one mile, and cause minimal damage. In
contrast, F3 tornadoes represent just over ten percent of the total,
but they have accounted for the majority of injuries and fatalities.
These tornadoes have the potential of causing severe damage to even
well-constructed houses, and they sometimes leave a path of
destruction several miles long.
Table 12-1. The Fujita scale for categorizing tornado damage.
Fujita
Scale |
Estimated Wind
Speed (mph) |
Typical Damage |
|
|
|
| F0 |
< 73 |
Light Damage - Some damage to chimneys; branches broken off trees; shallow-rooted trees pushed over; signboards damaged. |
| F1 |
73 - 112 |
Moderate Damage - Peels surface off roofs; mobile homes pushed off foundations or overturned; moving autos blown off roads. |
| F2 |
113 - 157 |
Considerable Damage - Roofs torn off frame houses; mobile homes demolished; boxcars overturned; large trees snapped or uprooted; light object missiles generated; cars lifted off ground. |
| F3 |
158 - 206 |
Severe Damage - Roofs and some walls torn off well-constructed houses; trains overturned; most trees in forest uprooted; heavy cars lifted off the ground and thrown. |
| F4 |
207 - 260 |
Devastating Damage - Well-constructed houses leveled; structures with weak foundations blown away some distance; cars thrown and large missiles generated. |
| F5 |
261 - 318 |
Incredible Damage - Strong frame houses leveled off foundations and swept away; automobile-sized missiles fly through the air in excess of 100 meters (109 yds); trees debarked; incredible phenomena will occur. |
Table 12-2. The strength of tornadoes and associated casualties in the Barren River Area.
Fujita
Scale |
Percent of
Tornadoes |
Total
Injuries |
Total
Fatalities |
| F0 |
24 |
5 |
0
|
| F1 |
39 |
25 |
0 |
| F2 |
25 |
24 |
4 |
| F3 |
12 |
104 |
8 |
| F4 |
0 |
0 |
0 |
| F5 |
0 |
0 |
0 |
Path of tornadoes across the Barren River Area are shown in Figure 12-3.
In some cases, tornadoes did not remain on the ground long enough to
create a clearly defined path of damage. In other cases, the same
tornado may have touched down more than once. The map shows the
expected orientation of tornado paths, with most paths running from
southwest to northeast or from west to east. While the region has not
been hit by an F5 tornado, history does not preclude such an event in
the future.
Figure 12-3. Tornado paths in the Barren River Area, 1950-2000.
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