One of the nice things about teaching today compared to when I started in 1982 is the availability of real-time weather-related images and animations. Here's a cool resource provided by the Space Science and Engineering Center at the University of Wisconsin-Madison. It shows 7 days of infrared satellite imagery in a 13-second loop. It moves pretty fast, but you can pause it to point out mid-latitude cyclones, Chinook arches, etc. CLICK HERE to watch it. This page provides several other viewing options, including GOES-East or West, infrared, water vapor, or visible, full-disk or continental US.
Another fun way to show current weather in motion is the WW2010 site provided by the University of Illinois. Once the page open, click on one of the image options, then select animate, choose the number of frames (4-96 hours), and then select "play" or advance the animation one frame at a time.