A Sign of Fall Valley Fog

Sunday morning dawned mostly clear and cool in Vermont and other places in the northeastern United States.

Fog in Burlington last March
Morning fog is actually most
common in late summer and fall.  

Some valleys, especially near rivers or other bodies of water, were socked in with fog, however.

The fog would burn off by midmorning in all places, so the rest of today is going to be nice.

The areas of fog are one sign of autumn.

The ground and the water have been soaking up the summer heat for months now. Nights are starting to get a little cooler as we approach autumn.

The cool nighttime air comes in contact with the warm, moist ground. The moisture combined with the cool air condenses, and you get fog in the valleys.

This morning fog will now be quite common in the calm of many early mornings now into October.

On the bright side, if you wake up to dense fog, chances are the day will be gorgeous.  The morning fog, which always burns off as the sun gets higher in the sky,  usually comes when there is a high pressure system nearby or overhead. And high pressure usually brings sunny weather.