21 December 2008

Crazy December Storm Track

Posted by Dan Satterfield

If your reading this blog from anywhere  in the Northern Hemisphere, you know how crazy the weather has been in December. Here in the Southeast USA, we have had warm and dreary conditions, with nearly 11 inches of rain in Huntsville. This is not a record though. Back in 1990 we had over 18 inches!

The West, and North have had bitter cold, and snow for most of the month. Blizzards in Seattle, Detroit, and heavy lake affect snow in Michigan, and New York.

Here in the Tennessee Valley, we finally got just a dose of what has been the rule up North. Bitter cold arctic air has moved in, and as I type this on Sunday night the first day of Winter, it is -7C!

So what happens next you ask? Well first let me explain why it has been so warm here, and cold elsewhere.

The storm track locked into a pattern in early December. (See below). This kept us wet and mild, while most of the country had snow, and cold.

The pattern broke this weekend, and the cold made it into the East and South.

It will not last though. The long range guidance is all advertising a return to the storm track of the last two weeks, with cold and snowy weather in the North and West, and mild wet weather in the southeast.

The image below is the storm track forecasted by the WRF model, for Christmas Eve. The upper left panel is the storm track, and the bottom right is the forecast of precipitation for the 12 hour period during the day. I’m always happier with the jet stream to my south….I love SNOW!



The map below is courtesy Penn State Meteorology.