Crystal Spring, Pensilvânia

...LOCALLY DENSE FOG WILL REDUCE VISIBILITY... Clouds are touching the tops of the ridges, making a fog that is reducing visibilities to less than a quarter of a mile in spots. Please use caution if you are driving overnight, especially over the ridge tops. Be prepared for significant changes in visibility over a short distance, slowing down as necessary. The clouds and fog likely won't improve much overnight, but will slowly improve during the morning.