9:05 p.m.: As the severe-weather threat diminished for metro Denver without major storms, large hail and rowdy storms were still occurring on the Eastern Plains Thursday night, particularly south and southeast of Limon. The National Weather Service said on Twitter that earlier in the evening, a spotter reported 3.5-inch-diameter hail in Lincoln County.
Thunderstorms and rainfall also were evident on weather radar Thursday night north of metro Denver in Larimer and Weld Counties.
7:40 p.m.: Most severe storm activity is occurring east and southeast of metro Denver on the Eastern Plains, but a severe thunderstorm watch is still in effect for the urban corridor through 10 p.m.
The National Weather Service issued a severe thunderstorm warning until 8:15 p.m. for Boyero and Lincoln County, warning of baseball-sized — or even “large apple sized” — hail. It also issued a tornado watch until 1 a.m. covering a wide area from Colorado Springs to western Kansas.
At Denver International Airport, the average duration of delays was improving, to just over an hour for departing flights, but delays had grown to about 40% of both departing and arriving flights for the day, according to FlightAware.
6:18 p.m.: The FAA lifted its ground stop at Denver International Airport, allowing incoming flights to take off from their originating airports, a little before 6 p.m. But it still has ground delays in place. Delays were averaging more than 90 minutes for departing flights, with arriving flights delayed an average of 30 minutes, the FAA’s advisory said.
Flight disruptions were adding up, with 371 departing flights delayed, or more than a third of the day’s schedule out of DIA, and 44 canceled, or 4% of the daily schedule, according to flight-tracking service FlightAware. Arriving flights were delayed or canceled at similar rates.
5:20 p.m.: Denver International Airport has a “ground stop” in place, meaning that by order of the Federal Aviation Administration, incoming flights may not take off from their airports of origin until the ground stop at DIA is lifted. The designation is common when severe thunderstorms are seen as likely or imminent.
5 p.m.: According to a special weather statement from the National Weather Service, a landspout is possible in parts of Arapahoe and Douglas counties, including Centennial, Parker and Castle Pines until 5:15 p.m. No hail is expected.
4:20 p.m.: According to a special weather statement from the National Weather Service, a landspout is possible in parts of Adams and Arapahoe counties including Aurora, Bennet, Centennial, Lone Tree, Strasburg and Watkins until 4:45 p.m. No hail is expected.
Metro Denver and Colorado’s Eastern Plains face the potential of “very large, damaging hail” as another round of storms looks likely to hit Thursday afternoon and evening, the National Weather Service says.
The NWS issued a severe thunderstorm watch until 10 p.m. for all counties in metro Denver, northern Colorado and northeastern communities including Fort Morgan and Sterling. And flights at Denver International Airport faced a ground delay as of 4 p.m., with the Federal Aviation Administration delaying some takeoffs and landings ahead of storms.
The weather service said Thursday’s storms also might bring damaging winds up to 80 mph, localized flooding and the threat of tornadoes. But the main threat was hail, which could reach golf ball to baseball size in some places.
In a mid-afternoon tweet, the weather service said areas east of Interstate 25 faced the greatest risk of severe weather. It forecasted storms along the I-25 corridor between 4 p.m. and 10 p.m., and on the Eastern Plains from 5 p.m. to midnight.
Just before 3 p.m., weather radar showed that some storms were already beginning to develop in the foothills, moving east onto the plains north of Boulder and in the south metro area.
