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Answer: Since fog is composed of tiny droplets, or in the case of ice fog tiny frozen crystals, separated by significant amounts of air, it could not and does not form a solid mass in the air, even when the particles themselves are frozen. The point regarding the air being less than freezing, though, is that water needs an appropriate surface upon which to initiate freezing at 32 degrees F, and droplets suspended in air will not typically freeze at that temperature unless they encounter something called an ice nucleus. Even then, with small droplets the ice nuclei are usually most effective at causing the droplets to solidify at temperatures below about 14 degrees F.
Nov. 6, 2009 | Tags: clouds, cold, visibility/fog/dust

Answer: It's pretty difficult to imagine any way in which the number of fogs in August would have any predictive value regarding snow events in the winter, apart from the fact that around here we typically have a few notable fogs in August and a few notable snows in winter, so over time the numbers could be similar. Also, one has to ask how dense the fog has to be to "count" as a "fog," (visibility under 3 miles, 1 mile, a half-mile?) and what counts in winter as a "snow" (a brief flurry, a trace of snow, measurable snow, an inch or more?). To answer your original question, though, fog was reported at the RDU airport on 24 days in August, with the visibility in fog falling below one quarter mile only twice. At Fayetteville, fog was reported on 28 days, with visibility below a quarter mile on three days.
Oct. 25, 2009 | Tags: folklore, past weather, visibility/fog/dust