Thursday, February 21, 2013

Thundersnow in Missouri

Winter Storm Q lived up to its forecast, dumping a foot of snow in Columbia.  The powdery flakes began to fall about 7:30 AM and, by late morning, snow was accumulating at a rate of 3 inches per hour, accompanied by frequent lightening and thunder.

Thundersnow, an uncommon phenomenon, is most likely to occur in late winter or early spring, when a potent storm system mixes relatively warm, moist air at the surface with cold, drier air aloft; the lightening and thunder usually develop during periods of intense snow, as occurred today.

A dry wedge has entered our region over the past hour and should last until "backside" flurries pass through later this evening; since the storm's central low is moving rapidly off to the northeast, we may miss any additional precipitation.  Nevertheless, the heavy blanket of snow, which stretches from west-central Kansas to western Illinois, should put a significant dent in our prolonged drought.  Unfortunately, to our south, a swath of ice, from eastern Oklahoma to the Ohio Valley was not as beneficial and severe thunderstorms, some tornadic, continue to rumble along the Gulf Coastal Plain.