Dolores schools reported that they went into lockdown after a funnel cloud was spotted Tuesday five miles northeast of Cortez about 2:50 p.m.
The lockdown ended about 3:15 p.m., when the National Weather Service lifted the warning. The school reported that buses would run on their normal schedules.
Weather spotter Jim Andrus called the twister in to the National Weather Service. He watched it for five minutes, and it didn't touch down.
A tornado warning was issued for northeastern Montezuma County from 2:50 p.m. to 3:15 p.m. Residents were advised to take cover, and the warning stated that a tornado may develop at any time. Cortez and Dolores were listed as towns at risk.
Doppler radar showed a dangerous storm in the area moving northeast at 10 mph.
"I saw a funnel cloud descend 500 feet below the base of the thunderstorm," Andrus said. "By the time I called it in, it had disappeared."
The tornado was sharply defined, he said, and was confirmed by bits of clouds that could be seen rotating around it.
He said the last reported funnel cloud in the region east of Cortez was 15 years ago.
Wind shear occurring at different altitudes helps to create the twisting winds of tornados, Andrus said.
"This one came and went was not a significant threat, but it's best to keep an eye out and report them right away," he said.
Mesa Elementary School in Cortez also reportedly went into a tornado lockdown as a precaution. Students were ushered into the hallways.
A National Weather Service tornado warning alerts the public to an existing tornado or one believed to be in existence. The service advises that in the event of a tornado, residents should take cover and move to a basement, an interior room on the lowest floor of a sturdy building. Avoid windows, and if you are in a mobile home or outdoors move to the closest substantial shelter and protect yourself from flying debris.