The fog reduced visibility to nearly zero in some locations.
The Sky6 cameras were proof of that.
What an amazing shot of the skyline. You can clearly see the fog that is reducing visibility to near zero in some spots this morning. You can also see the sun rising. We'll see some sun mixing with the clouds today. @6abc pic.twitter.com/TqZ1F18GeG— Karen Rogers (@karenrogers6abc) September 25, 2020
The fog made the Philadelphia skyline disappear at times.
According to AccuWeather: "Fog is essentially a low cloud and can either form in place or physically move into an area."
The National Weather Service issued a dense fog advisory for the entire region until 10 a.m.
"Not every locale is seeing dense fog but throughout the region there are areas of dense fog with visibility near or below a quarter mile," the NWS said.
Areas of fog have developed across the region and should persist through mid morning. If you are driving this morning, please exercise caution for rapidly changing visibility. #mdwx #pawx #dewx #njwx pic.twitter.com/d6ZgzqlkMF— NWS Mount Holly (@NWS_MountHolly) September 25, 2020
The fog will give way to some sunshine for the rest of Friday. Then the rain moves in for Saturday.