If the dew point number is within one or two degrees F you'll get fog. If the dew point is 40, and the temp is between 38-42 degrees F you'll likely have fog.
Ok. Now explain Accuweather's RealFeel temperature.
We pray our sights be straight and our aim be true We pray for no pain to the game we pursue We thank you Lord for this land We thank you for the sights from our stands We pray for safety, one and all We pray we may return next fall