Analysis valid 1:00pm EST 13 Jan 2011
There are two main systems that dominate the current weather discussion for today. First, a low pressure system stationed off the coast of the Northwest is pumping rain and moisture onshore, bringing heavy rainfall amounts to northern California, Oregon, and Washington. Secondly, a band of snowfall is moving east-southeast through Minnesota and Iowa towards Illinois and the Great Lakes Region. The 500mb vorticity map shows vertical motion support for both systems through positive vorticity advection. The 850mb map also shows vertical motion support for preciptation with warm air advection in both locations. In addition, the 850mb map shows a warming trend for the Great Plains moving east towards the Ohio River Valley.
today's current weather graphic was produced by Kevin Van Leer and Talon Atwell