By Judson Jones, CNN Meteorologist
A tornado, first reported as a landspout before it fully developed, could be seen from the ground and from the air Monday afternoon across Weld County in Colorado.
The landspout was first spotted near Firestone. As it moved northeast, toward Platteville, it became a “well-developed tornado,” according to trained storm spotters.
National Weather Service employees took photos of the tornado as it developed in Frederick and north of Longmont.
No injuries were reported, though there was damage, according to tweets by the Weld County Office of Emergency Management and the weather service.
“We’ll be doing a damage survey on Tuesday, June 8th and provide details as they become available,” the National Weather Service in Boulder wrote on its website. “We’ll have details, including the exact tornado path, damage assessment, and EF rating.”
“Weld County, where the tornado formed, is the No. 1 county in the US for producing tornadoes,” CNN meteorologist Brandon Miller said.
“Tornadoes in Colorado are typically short-lived and on the weaker side (usually EF-0 or EF-1 on the Enhanced Fujita Scale) and are often referred to as landspouts.”
Like their counterparts — waterspouts — that form over water, landspouts are not produced by supercell thunderstorms like the larger and more destructive tornadoes that are known to form over the Great Plains.
They are typically narrow, rope-like condensation funnels that form while the thunderstorm cloud is still growing and there is no rotating updraft, according to the National Weather Service.
“Landspouts in Colorado generally spin up in more ordinary thunderstorms that rotate due to changes in winds that occur because of the drastic changes in terrain,” Miller explains.
As Monday’s storm strengthened, the landspout-turned-tornado was visible from miles away. Denver news stations filmed the storm from helicopters — from a safe distance away. Images and videos also appeared online from people onboard flights to Denver International Airport.
It’s not unheard-of to see tornadoes from some distance in the Plains.
“In this case, there was only a single storm that formed north of Denver and the airport, which made it easier to see from the plane,” CNN meteorologist Dave Hennen said.
This storm system did cause some weather delays Monday afternoon at Denver International Airport, airport officials said via their official Twitter account.