Colorado Hail Swath, Not Snow, Was Visible From the Air Days After Monday's Storm

Jonathan Erdman
Published: May 17, 2018

A series of hailstorms in northern Colorado earlier this week deposited enough hail to leave swaths that appeared like areas of snow as seen from several flights.

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One strip of small hail near Wellington, Colorado, was flown over by Jane Carpenter, a pilot at Leading Edge Flight Training, located at the Northern Colorado Regional Airport. She documented the event in photos provided to KUSA 9News meteorologist Cory Reppenhagen.

A closeup (left) and wide view (right) of a hail swath near Wellington, Colorado, deposited by a hailstorm on May 14, 2018.
(Jane Carpenter, First Class Flight Training)

The hailstorm struck Monday afternoon near the town about 60 miles north of downtown Denver, producing enough small hail to cover a short stretch of Interstate 25.

A high-resolution satellite image from NASA's Terra satellite taken the following day showed the approximately 2.5-mile-long swath clearly visible under a cloudless sky east of the Colorado High Country.

The Wellington, Colorado, small hail swath, denoted by the arrow, as seen from NASA's Terra satellite on May 15, 2015, one day after the hailstorm struck near the northern Colorado town. The swath was estimated to be 2.5 miles long.
(NASA)

Carpenter flew over the swath Tuesday morning and said in a Facebook post that in 25 years of flying, she had never seen anything quite like it from the air.

A small area of the original hail swath remained on the ground into Wednesday despite a high of 83 degrees at nearby Northern Colorado Regional Airport, according to a photo shared by Carpenter.

The Wellington, Colorado, hail swath on May 16, 2018, two days after the hailstorm, as seen from the air.
(Jane Carpenter, Leading Edge Flight Training)

Merritt Dupon, who lives in the hail swath, told Reppenhagen there was up to 2 feet of accumulated hail measured in some areas.

(MORE: America Has a Distinct Hail Alley)

This wasn't the only hail swath on the High Plains.

Several inches of hail as large as quarters prompted snow plows to be called out in The Pinery, a southern Denver metro suburb.

Multiple hail swaths in northern Douglas, northern Elbert and far eastern Arapahoe counties could also be seen in satellite images as skies cleared later Monday afternoon.

Some of these could also be seen from the air, as Katie Sloop noted on her flight to Denver Monday afternoon.

A much longer hail swath, or several individual swaths, were deposited in western Kansas and might have stretched into parts of eastern Colorado Monday.

Up to 6 inches of baseball-size hail accumulated in Lane County, Kansas. The huge hailstones smashed windows in two homes north of Leoti and south of Sharon Springs.

(MORE: Hail is the Most Underrated Costly Weather Disaster)

That evening, the cold accumulated hail contrasting with warmer ground made the hail swath visible in infrared satellite imagery.

The High Plains of Colorado and Kansas are among the areas most frequently impacted by hail each year in the United States.

According to the Storm Prediction Center, hail at least 1 inch in diameter falls nine to 13 days each year, on average, along the Front Range of Colorado and High Plains of Kansas and Nebraska.

Jonathan Erdman is a senior meteorologist at weather.com and has been an incurable weather geek since a tornado narrowly missed his childhood home in Wisconsin at age 7. Follow him on Facebook and Twitter and subscribe to The Weather Channel podcast.


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