In this decade, Colorado has averaged around 60 tornadoes a year. However, this is quite variable from year to year. A record was reached in 1996, with a a total of 98 tornadoes reported. In 1998, 38 tornadoes were reported. Increasing population, improved communications, and more trained spotters have all resulted in more reported tornadoes each decade since the 1960s.
Most of our tornadoes are weak, with wind speeds of less that 110 mph. But Colorado is occasionally visited by strong tornadoes. Six tornadoes in 1996 were comparable to the Limon tornado of 1990 in strength, with winds of 150 to 200 mph.
Tornadoes have been reported 9 months of the year, and the peak season for tornadoes extends from mid May through mid August. Two thirds of Colorado's tornadoes develop in May and June.
In Colorado, the primary threat of tornado is east of the Continental Divide along the Front Range and foothill counties. On the eastern plains tornadoes occur every year, particularly during the spring and summer. Fortunately, the loss of life is rare and property damage is usually minimal. However, as the population grows in eastern counties our vulnerability for more damaging tornadoes grows.
The severity of a tornado is based on windspeed and the amount of property damage incurred. A major problem in responding to tornadoes is the short time they take to develop, their erratic movement and the tremendous forces they expend.
- Colorado is ranked ninth in the country for number of tornadoes.
- A tornado may be the most violent phenomenon found in nature. Winds can easily exceed 200 mph.
- Colorado residents can expect an average of forty tornadoes every year.
- The June 1990 Limon Tornado caused $12 million in damages.
- Most tornadoes occur between May and July. The major threat of tornado is in the afternoon or evening hours.
- More than 75% of tornadoes occur between noon and seven p.m. Tornadoes usually move from southwest to northeast.
The National Weather Service offers training courses for volunteer severe weather/tornado spotters. NOAA weather radio can provide supplemental warning to public systems. Individuals can purchase tone-activated radios at a nominal fee.
Tornado Safety Tips
When a tornado watch is announced, it means conditions are present for a tornado.
Keep a radio/TV tuned for further information, and gather emergency supplies.
When a Tornado Warning is issued, it means a tornado has been sighted or is imminent. Take shelter immediately.
If you are at home:
Go to your basement. If you have no basement, go to an interior hallway or small interior room on the the lowest floor.
Do not remain in a trailer or mobile home if a tornado is approaching. Take cover elsewhere.
If you are at work:
If you are at school:
If you are in a car or outside:
Mitigation Tips for Tornadoes
Colorado communities, and in particular eastern plains communities, must prepare and educate residents for the possibility of tornadoes - especially in May, June and July. Mobile home parks should require tie-downs and provide alternate shelter for residents. Communities can purchase warning systems and individuals can purchase inexpensive tone-activated radios. Construction restrictions should place an emphasis on designs that can withstand tornadoes and other high winds.