Monday, October 24, 2016

Summer in October

Summer-like heat has enveloped the Front Range urban corridor and is expected to persist for the coming week.  A high pressure dome, centered over the Four Corners Region, is deflecting Pacific cold fronts to our north and producing downslope air flow east of the Continental Divide; these atmospheric and topographic phenomena combine to heat up and dry out the air as it drops toward the Colorado Piedmont.

Here in Metro Denver, our afternoon high is approaching 80 degrees F.  Though the October sun is lower in the sky, the intense sunshine, dry air and thin atmosphere deliver plenty of heat at the surface.  On the other hand, cloudless skies, low humidity and a high elevation combine to augment radiation cooling at night and our early morning and late evening temperatures are distinctly un-summer-like (falling into the low fifties after sunset and near 40 degrees F by sunrise).

Despite the warm afternoon weather, the autumn colors are past peak, the first winter songbirds have arrived and migrant waterfowl continue to increase in number and variety on regional lakes.  It may feel like summer at midday but the seasons are progressing and the first snow flakes in Denver are already overdue.