Big selection of weather maps from Prof. Jon Kahl at University of Wisconsin in Milwaukee
Ohio State weather server. Timely, useful graphical and textual weather data incl. GEOS satellite images.
Click US map or select region/city.
National Weather Service flagship: Interactive Weather Information Network has tons of data - text/graphical format.
A simple text based weather service using city codes.
Complete source of graphical weather info. For professionals and casual users. Graphics and data displayed as a meteorologist would expect. Detailed explanations for novices.