DENVER — More than 600 flights were delayed or canceled at Denver International Airport on Thursday afternoon as storms moved through the Front Range.
According to FlightAware, as of 9:00 p.m., DIA had 679 delayed flights and 30 canceled flights.
Delays were affecting Southwest, United, SkyWest, Frontier and other airlines. Of the canceled flights, most were SkyWest.
A spokesperson for DIA said the airport was on a ground stop for much of the afternoon.
Another round of rain moved into the metro area Thursday afternoon, with some severe weather possible for Denver and the Front Range. Some bands of heavier rain are possible in the afternoon and evening and into Friday morning.
The National Weather Service for Boulder said in a special weather statement that wind gusts up to 30 mph and penny-sized hail were possible at DIA earlier Thursday afternoon.
In Northern Colorado, a Flash Flood Warning was in effect for the Cameron Peak burn scar until 4:30 p.m. The National Weather Service said rainfall rates were exceeding 2 to 2.5 inches an hour.
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What is Severe Weather?
According to the National Weather Service, there are five specific types of weather that can qualify as "severe." They are tornadoes, floods, lightning, hail and wind.
RELATED: What is severe weather?
A thunderstorm is considered severe when winds reach at least 58 mph and/or contains hail at least 1" in diameter. When these conditions are met, the NWS will issue a severe thunderstorm warning.
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Lightning and heavy rain are not included, but often accompany severe thunderstorms.
The National Weather Service will issue a flash flood warning when the flooding is already occurring or imminent. A flash flood watch means that conditions are favorable for a flash flood and those in the area should keep a close watch.
A tornado watch is issued by the NWS when they determine that weather conditions are favorable for the formation of tornadoes. They usually last for a long time, cover a large area and begin well before any tornadoes or other severe weather begin.
A tornado warning is issued if a tornado is indicated by radar or reported by weather spotters. They are generally for a much smaller area and only last for about 30 minutes. If a tornado warning is issued in your area, you should seek shelter immediately.
