You may be surprised to learn that counties with major cities and high-priced real estate are some of the most at risk for tornado damage.
Chicago, Houston, Plano (Dallas Metro), St. Louis and Kansas City are all in counties that rank as the most vulnerable to damage.
Gutter Gnome analysts crunched the numbers, looking at several factors:
The age of the homes, between 24.5-70 years, accounted for 17% of the rank. The share of mobile homes ranged from 0.06%-42% and accounted for 12% of the final rank. State adoption of international residential building codes, ranging on a scale from 0 (no adoption) to 18 (most adoption), also accounted for 12% of the score.
HOW YOU SHOULD PREPARE FOR A TORNADO
Cook County, Illinois, took the top spot in the overall ranking. The Chicago Metro area had a tornado risk score of 99.97 out of 100. The average age of homes was 59.7 years, and only 0.77% were mobile homes. Illinois is tied for the lowest state adoption of residential and building codes. The annual expected loss from tornadoes is $304 million.
WHERE ARE TORNADOES MOST COMMON?
Harris County, Texas, took the second spot. The Houston Metro area scored 100 out of 100 for tornado risk. The expected annual loss came in at $354 million. The average age of homes is relatively young, at 39.2 years, with 2.6% of them mobile homes. Texas has a moderate adoption of building codes.
TORNADOES HIT LARGE CITIES: THIS IS WHY
Collin County, Texas, which is northeast of Dallas, comes in No. 3. The home of Plano has a 99.94 tornado risk score and a total expected annual loss of $358 million – the most expensive. About 1.7% of homes are mobile homes, and the average age of all homes is 27.58 years.
HERE’S WHERE TORNADOES ARE MOST LIKELY TO OCCUR IN EACH MONTH
In the fourth spot is St. Louis, Missouri, with an average home age of 70 years – the oldest average home age on the list of over 900 counties. The state is tied for the least adoption of building codes. The county which includes St. Louis has a low share of mobile homes, 0.34% and a tornado risk of 98.6 out of 100.
Rounding out the top five, Jackson County, Missouri, also has a small share of mobile homes, under 1% and the average age of homes is 53.87 years. The expected annual loss for the home of Kansas City is $54.5 million with a tornado risk score of 99.59 out of 100.
YEARLY TORNADO DEATH TOLL SPIKES IN 2023 DESPITE AVERAGE SEASON
The U.S. averages about 1,333 tornadoes a year. Half of those usually form between April and June. The second tornado season comes in the fall. Canada comes in second with just hundreds.
Texas is by far America’s most active state for tornadoes, averaging 151 twisters each year. In a distant second place is Kansas, with an annual average of 91 tornadoes. This is an area some call “Tornado Alley.”
Seven of the top 10 counties with the highest total expected loss are in Texas. Gutter Gnome nicknamed the area the “Texas Triangle.”
Missouri, Kansas and Illinois counties placed high on the list because the states have not yet instituted building codes that mandate things like stronger roofs, safe rooms and impact resistant windows, explained Gutter Gnome.
WHY TORNADO ALLEY IS SHIFTING EAST