I was just watching our local 600-mile animated radar loop on The Weather Channel website when I spotted something kind of strange over by Ft. Wayne. I looked at the same radar for their area and saw it again. It was just there for one or two segments of the loop -- was that a tornado? Check it out (had to do a screen print, LOL). It's so cool having a weather forum for this kind of stuff!
Probably it's feed back from the Fort Wayne Doppler. We get lines out over Lake Erie from the local Erie PA Doppler that look like nasty squall lines sometimes and a similar doughnut pattern around the radar location. Wonderful and strange stuff.
Anomaly, yeah, exactly. They use that on Star Trek TNG a lot, too!
Screen prints using Windows software:
Press the PRT SCR key in the upper left of the keyboard. That copies whatever's on your screen to the clipboard. Then open your favorite image editor and select EDIT > PASTE. Crop it however you want, add bells and whistles, and save-as whatever file name and format you want. For the best readability, especially pages with a lot of white with text, save in a very low compression JPG (85% quality, at least). You can experiment and see how it looks by doing a save-as GIF file, too.
There are programs which automate the screen print process, including capturing entire window contents (even the part not visible without scrolling). There's a thread going into more depth about those over in Computer Talk: http://davesgarden.com/forums/t/449691/