Wednesday, June 24, 2015

Supercell over Denver

Though we enjoyed a warm, sunny day in Metro Denver, a stationary front stretched across northeastern Colorado, adding instability to the atmosphere.  As the daytime heating peaked in late afternoon, thunderstorms began to form above the Front Range, drifting eastward across the urban corridor.

About 4:30 PM, one of these storms suddenly intensified.  Drawing in heat and moisture from the surrounding Piedmont, it rapidly grew into a massive supercell, rising to an altitude of 50,000 feet.  Soon, torrential rain, hail, 60 mph winds and intense lightning ravaged the northern 2/3 of the Metro area.  Moving slowly to the ESE, the storm dropped two inches of rain in 30 minutes, triggering flash floods.  While radar and the observation of weather spotters indicated the presence of a tornado, no evidence of a touchdown (i.e. surface damage) has yet to be documented.

Within an hour, the storm was moving off across the Eastern Plains and had lost some of its intensity.  Here on our Littleton farm, in southwest Metro Denver, we received torrential rain but were spared any wind or hail damage. However, until that stationary front lifts to the north or drops southward through our region, it will be a focal point for recurrent storm development.