Radiation Fog

While preparing my lunch for the week, I noticed the fog had cleared from Rhinebeck.  I wondered if it cleared from the Hudson.  I saw some fog to the west in the vicinity of the river.  It was worth a shot.  

As described by Hudson Valley Weather:

"Sunday was a very interesting day meteorologically. A good part of the region saw lots of sunshine, and afternoon highs in the low to mid 50s... and in those areas, it was a gorgeous December day.

However, valley areas along the Hudson River (primarily north of Newburgh), experienced a much different day on Sunday. A dense, persistent radiation fog settled in prior to dawn on Sunday, and due to the calm winds and the Catskill mountains, north of Poughkeepsie... it never burned off. In those areas, afternoon highs didn't break out of the 30s... thanks to the dense fog trapping the cold air at the surface, and not allowing the sun to warm the air.

The Hudson Valley can have an event like this during the late fall and early winter, because the valley is sheltered by the Catskills on the west, and the Taconics to the east. After a mild day Saturday, as the cold dense air settled into the valley Saturday night, the air cooled... condensed... and radiation fog formed (due to radiational cooling). This was likely enhanced by the relatively warm Hudson River. With the very calm winds on Sunday, the fog was trapped within the valley, and simply never burned off in some areas. In ideal geographical areas, if the winds are calm for an extended period... the fog can persist for days... until the winds strengthen, and mix the atmosphere.

Here's a snapshot of the visible satellite image from 12pm on Sunday. It was feast or famine, as half the area saw sunshine and blue skies, and temps in the 50s... while the other half of the area saw dense fog, and temps in the 30s. Either way... we hope you had a nice Sunday."

Though not as interesting as the fotos taken at Breakneck, seeing the fog lined Hudson provided a wonderful view.  The views south towards Port Ewen were the most interesting, with the mountains jutting through the clouds.  Unfortunately the sun rested directly above.  Still, I consider myself fortunate to be able to get out and witness such an occasion.  

Lots of cool shadows