The image of Colorado that comes to mind for most includes snowcapped peaks, frosted evergreens, and skiers happily cruising down the slopes. Certainly, this vision is what our tourist industry likes to project and, fortunately, we do have a winter season that offers much more cold weather enjoyment than in many other parts of the country.

Our cold season extends far longer than most, thanks to the fact that Colorado is the state with the highest average elevation. The first hints of winter often appear at the same time many neighboring states are still sweating out the dog days of summer.

By the beginning of September, the weather in Colorado starts the annual shift from a summer pattern to a mix of fall and winter. Just a week or two after Labor Day, something seems to be missing in our Colorado weather routine -- the nearly daily round of afternoon summer thunderstorms!

The shorter days and lower sun angle bring an end to the thunderstorm season, as the decrease in daytime heating prevents the strong convective lifting that helps afternoon storms to pop up. In addition, the middle and upper levels of the atmosphere are comparatively warm after the long summer, so the air becomes relatively stable -- cooler near the ground and warmer aloft.

Although the official end of summer is not until the third week of September, for most in Colorado, the real psychological end of summer is marked by the Labor Day weekend.

After Labor Day, weather thoughts turn away from thunder and lightning and start to center on the annual golden glow of the aspen and the fall of the first snow. Usually the gilded glory of the forest is accompanied by light, early snowfalls in the high country; one morning, usually just shortly after the start of football season, a thin veil of fresh snow will suddenly show up on the high peaks along the Continental Divide. Often it disappears by midday, but it marks the beginning of a new snow season for our mountains and serves to remind us that the warmth of summer is drawing to a close and that the cold season will soon be upon us.