Dense Fog in San Juan River Basin, Colorado

Dense fog was observed across the San Juan River Basin, including at the Stevens Field - Pagosa Springs Airport where visibility was reduced to less than one quarter of a mile for several hours.

On the night before the event, a winter storm brough rain and snow to the southwest Colorado valleys. Following this, a dry slot moved overhead during the early morning hours. The combination of increased valley moisture and clearing skies led to the development of areas of dense fog across the southwest Colorado valleys which lasted until precipitation returned again in the afternoon.