What to know about Colorado's deadliest natural disasters, including key safety tips

Spring in Colorado is a mishmash of weather, and that chaotic weather produces the convergence of many of the state's greatest natural disaster threats, including flash floods, wildfires, avalanches, tornadoes, lightning and hail.

Larimer County has a long and deadly history with many of these disasters, which are a threat year-round.

Here's a look at the top five natural disasters in regard to biggest threat to human life and safety, plus how to prevent becoming a victim.

Flooding has killed more people in Colorado than any other natural disaster

• Deaths: More than 500 people have died in floods in Colorado since the turn of the century, according to Western Water Assessment at the University of Colorado.

• Prime months: June to September but can also occur in April and May.

• Larimer County connection: The county has been home to multiple killer floods, including the deadliest flood in state history and the most recent flood deaths. The Big Thompson Flood on July 31, 1976, killed 144 people. The most recent flash flood deaths came in the Cameron Peak Fire burn scar. The latest killed a mother and young daughter on Crystal Mountain up Rist Canyon on July 15, 2022. Four family members died in the Upper Poudre River in the Black Hollow Flood on July 20, 2021.

• Safety tips: In July 2022, the Larimer Emergency Telephone Authority added new ways to receive flash flood alerts. Subscribe to alerts at nocoalert.org. Purchase a NOAA weather radio that reliably broadcasts weather service warnings, watches, forecasts and other hazard information 24/7 and continually monitor. If in a prone area — even if during rain you don't see flooding — be prepared to swiftly move to higher ground because there may be a delay in the flooding reaching you. Do not attempt to cross floodwaters by walking or with a vehicle.

Avalanches are second-most fatal natural disaster in Colorado

• Deaths: Since 1950, 319 people have died in avalanches in the state, nearly double the next closest state and accounting for around 25% of U.S. avalanche deaths.

• Deadly season: This season alone, Colorado accounts for 10 of the 22 U.S. avalanche deaths. The state averages six deaths per season.

• Prime months: January through March are deadliest, but months on either side of those also claims lives. During the 2021-22 season, the final death of the season occurred May 29, 2022, on Mount Meeker in Rocky Mountain National Park.

• Larimer County connection: More than 10 people have died in avalanches in Larimer County, mostly in the Cameron Peak and Rocky Mountain National Park areas. Pitkin and Summit counties have had by far the most people killed in avalanches, both with more than 40.

• Safety tips: Check the detailed avalanche forecast on the Colorado Avalanche Information Center's website, avalanche.state.co.us, before your trip and continue to monitor the conditions at your location. Go in groups but have only one person travel through potential avalanche terrain at a time. All members of the group should be equipped with avalanche safety gear, including an avalanche transceiver, probe pole and shovel, and be trained to effectively use them.

From the archives: New Colorado avalanche forecast tool makes avoiding killer slides easier

Lightning causes third-most deaths in Colorado, and Larimer County ties for most deaths

• Deaths: 100 since 1980, ranking Colorado near the top five nationally on average.

• Prime season: May through September are the deadliest months. Most often occur on weekends, especially Saturdays, from noon to 6 p.m.

• Larimer County connection: The county is tied with El Paso for most lightning-related deaths, with 10 since 1980, and is second to El Paso (84) in injuries with 76 since 1980, according to the National Weather Service.

• Last time: The last lightning death in Larimer County happened Aug. 19, 2016, near Red Feather Lakes. In Fort Collins, two men were fatally struck by lightning on the Colorado State University campus in July 2008.

• Colorado lightning strikes: Colorado averages just less than 500,000 cloud-to-ground lightning flashes per year, which ranks 32nd by per square mile among states.

• What are the chances?: About 10% of those struck by lightning die, leaving 90% with various degrees of disability. The odds of being struck in a given year are roughly 1 in 1.2 million. The odds of being struck in a lifetime (80 years) are 1 in 15,300.

• Thunder to lightning count: You can roughly calculate the distance by counting the number of seconds between the flash of lightning and the sound of thunder, and then divide by five; 5 seconds = 1 mile.

Here are a few lightning safety myths and the facts to remember instead:

• Myth: Crouch if caught outside during a thunderstorm. Fact: Crouching is no longer advised because it doesn't make you any safer outdoors. Lying on the ground is worse. Run to a substantial building or vehicle.

• Myth: If it’s not raining or there aren’t clouds overhead, you’re safe from lightning. Fact: Lightning often strikes more than 3 miles from the center of the thunderstorm and up to 15 miles.

• Myth: Rubber tires on a car protect you from lightning. Fact: It's true that most often vehicles are safe from lightning, but it is the metal roof and metal sides, not the rubber tires, that protect you because when lightning strikes a vehicle, it goes through the metal frame into the ground — so don't be touching anything metal inside. The same goes inside a house, so stay away from corded phones, electrical appliances, wires, TV cables, computers, plumbing, metal doors and windows.

• Myth: Taking shelter under a tree is safe. Fact: Height, pointy shape and isolation are dominant factors of where a lightning bolt will strike, so this is not a good option.

Wildfires are Colorado's fourth-deadliest natural disaster, and firefighters bear the brunt of fatalities

• Deaths: Since 1950, 47 people reportedly lost their lives in wildfires, including 29 firefighters or firefighter pilots. Fourteen of those firefighters lost their lives July 6, 2014, when overrun by flames while fighting the South Canyon Fire on Storm King Mountain near Glenwood Springs.

• Prime season: Historically, June and July, but that has changed in recent years. Seven of the past eight wildfires exceeding 10,000 acres since 2020 have occurred outside of that time frame, with the other wildfire starting July 31.

• Larimer County connection: It's home to multiple wildfires, including the state's largest — the 2020 Cameron Peak Fire, with a burn perimeter of nearly 208,913 acres — and sixth-largest — the 2012 High Park Fire, which had a burn perimeter of 87,284 acres. Four of the last six firefighter pilots to die have lost their lives in the county, three in two separate crashes fighting the 2002 Big Elk Fire near Estes Park and one during the Kruger Rock Fire near Estes Park in November 2021 in what is believed to be the state's first fixed-wing aircraft night firefighting mission.

• Safety tips: Don't leave campfires unattended and make sure to extinguish campfires until cold to the touch. Properly extinguish and dispose of cigarettes. Obey fire restrictions. Clear vegetation at least 30 feet away from cabins and houses, ensure roof has a Class A fire rating and remove all leaves, needles and other debris from decks, roofs and gutters.

Tornadoes/hail are distant fifth in natural disaster deaths but cause extensive damage

• Deaths: Five tornado fatalities and one hail fatality since 1950.

• Prime season: About 75% of tornadoes occur in May, June and July, and the bulk of hail comes in June and July.

• Larimer County tornado connection: The Windsor tornado on May 22, 2008, started in Weld County but strangely moved northwest into Larimer County, just missing Fort Collins. The EF3 tornado was on the ground for 39 miles with wind speeds in excess of 165 mph, causing an estimated $147 million in privately insured damages and $193.5 million overall, making it the state's costliest tornado damage in state history. It injured 78 people and killed one, which was the last tornado fatality in Colorado.

• Larimer County hail connection: On July 30, 1979, a storm that produced, at the time, a record 4.5-inch hailstone resulted in the death of 3-month-old Jolene Kappelma. She was struck in the head by a hailstone while in the arms of her mother, who was seeking shelter from the storm inside the McDonald’s at 1250 W. Elizabeth St., according to the Coloradoan. According to NOAA records, since 2000 only four people have been killed by hail nationally.

• Colorado tornado count: The state averaged 46 tornadoes per year from 1992 to 2021, with the majority of those occurring in Weld County, according to the National Weather Service Storm Prediction Center. More than 90% of tornadoes are EF 0 or 1, the lowest on the Enhanced Fujita Scale.

• Deadliest tornado: On Aug. 10, 1924, a tornado killed 11 people, including nine children at a gathering on a farm northeast of Thurman in Washington County. It is the deadliest tornado on record in the state.

• Costliest hailstorm: A May 8, 2017, hailstorm caused more than $2 billion in damages in the Denver metro area.

• "Hail Alley'': The intersections of Colorado, Nebraska and Wyoming usually have the most hailstorms, averaging seven to nine hail days per year, according to NOAA, but the Denver metro area is not far behind.

• Safety shelter tips: A basement or lowest floor of a building offers the greatest safety. Next are interior rooms such as a bathroom, closet or interior hall on the lowest floor. If you have time, close all doors to your area for greater protection. If possible, get under something sturdy like a heavy table and protect yourself from flying debris with pillows, heavy coats, blankets or quilts. Do not stay in a mobile home.

• Outdoor safety tips: If there is no shelter nearby, get into the nearest ditch, low spot or underground culvert. Lie flat, covering your head with your hands. Vehicles are not safe places. Only remain in your vehicle if there's no better protection, but do not take shelter under a highway overpass.

This article originally appeared on Fort Collins Coloradoan: Colorado's deadliest natural disasters and how to avoid them