Foggy start to the day in Budapest, Hungary
This photo shows the capital of Hungary, Budapest, under a blanket of fog on a cold, winter morning. Only a 666 ft (203 m) high chimney is able to peer through the thick fog. This is an example of valley fog or radiation fog that often forms in low-lying areas on cold clear nights, especially in fall and winter. During the nighttime hours as the surface cools, if the dew point is reached, fog will hug the ground, with a layer of warmer air above — an inversion layer. In most cases, the foggy mantle is relatively shallow (tens of feet), but on occasion, it’ll extend several hundred feet above the surface. Because this phenomenon was forecast, I positioned myself high above Budapest on Harmahatar Hill (1,575 ft or 480 m high) a little before daybreak in order to capture this scene. The atmosphere above the inversion layer was quite clear, thus the Matra Mountains, some 50 mi (80 km) distant, could be seen on the eastern horizon. Photo taken on January 17, 2011.