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Tornado season: A historical look at Colorado's unpredictable spring weather

Posted at 2:52 PM, May 22, 2019
and last updated 2019-05-26 22:16:37-04

DENVER — The severe weather outbreak Sunday that spawned tornado watches and warnings up and down the Front Range and eastern Colorado came less than a week after Denver woke up to a record low temperature of 30 degrees and late-season snow Wednesday morning.

Colorado's extreme weather events have made forecasting in the Centennial State challenging at times. From mountain tornadoes to snow in June, Colorado spring weather can get a little tipsy and should be told go home. But tragically at the same time, it can turn deadly and be destructive.

Tornado season
Colorado is entering peak tornado season. The state sees an average of 27 tornadoes during May and June, with June being the busiest month with an average of 17 tornadoes, according to the National Oceanic and Atmospheric Administration. There have been 2,125 tornado events recorded in Colorado and at least five deaths related to twisters since 1950.


The first tornado of the 2019 season hit Colorado on March 22. A "landspout tornado" touched down in Weld County. A landspout tornado is defined as a weak tornado that is caused by swirling wind being drawn up by a thunderstorm.

The most tornado-prone county in Colorado and the entire country is Weld County, which has seen 268 tornadoes since 1950. The city and county of Denver has seen 16 tornadoes in the same period, the most powerful — an EF-3 — hitting on June 15, 1988. The strongest tornado to hit the state was an EF-4 in 1977, according to NOAA.

The tornadic activity doesn't always occur in the usual places in Colorado. Although extremely rare, tornadoes and funnel clouds have been spotted on the Western Slope and in high-altitude areas.

There have been three tornado touchdowns in Park County -- June 8, 2014, August 18, 2009, and August 23, 2008. In 2011, a tornado was documented on Mount Evans with an elevation of 11,900 feet. And on June 20, 1975, an F2 tornado touched down in Pitkin County.

On Monday, the National Weather Service received a report of a funnel cloud and possible tornado over Black Ridge south of Fruita on the Western Slope. Mesa County has only had 10 reported tornadoes since 1950.

Sunday's storms spawned several tornado warnings and watches. A tornado briefly touched down near Wiley in Prowers County Sunday afternoon. The sheriff's office said the twister was on the ground for about a minute. There were no reports of injuries or damages.

Spring snowfall in Denver
It's no secret (especially to locals), the inclusion of snow in any springtime forecast in the Denver area is not that unusual. In fact, in the last ten years, the date of the last measurable snowfall for the Denver area has occurred in May more often than not. The latest date of measurable snow in Denver occurred on June 2, 1951, when 0.3 inches fell.

Here are the dates of the last measurable snow for the Denver area in the previous 10 years, according to the National Weather Service:

April 24, 2018
April 29, 2017
April 30, 2016
May 10, 2015
May 12, 2014
May 2, 2013
April 3, 2012
May 11, 2011
May 12, 2010
April 27, 2009

Prepare for severe weather
Be prepared for severe weather when it strikes. Follow these tips provided by the Colorado Office of Emergency Management:

  • Build an emergency kit and make a family communications plan.
  • Identify a safe shelter location – a basement is best, followed by interior rooms on the lowest level of the building away from windows. Mobile homes are often unsafe in a tornado – identify a neighbor's house or public shelter where you can go if a tornado warning is issued.
  • Secure outdoor objects that could blow away or cause damage during a storm.
  • Unplug any electronic equipment before the storm arrives.
  • Obtain a NOAA Weather Radio (link is external) to receive alerts about impending severe weather.
  • Sign up for reverse telephone alerts (link is external) for your county, and don't forget to include your cell phone.
  • Make sure you have sufficient insurance coverage – including flood insurance, which is separate from your homeowners or renters policy.
  • Photograph or take video footage of the contents in your home in case you need to file a claim after a disaster.
  • Store copies of your important documents in another location, such as a bank safe deposit box.