Weird doppler-radar images

PIT2

Does anyone know what could have caused these kinds of doppler-radar images:

http://img452.imageshack.us/img452/909/ind23br.gif

More radar images of the same event:
http://www.softspotopening.com/

waht

Looks like it originated from Indianapolis. I have one word: NASCAR

scott1

It's moves out.It could the jetsterm(or somthing elese) breaking up the storm.That line appers in the east is probally just an error by the radar

russ_watters

I don't see anything weird in that gif - to what are you referring?

Evo

Thanks, I was wondering if I was the only one that wasn't seeing things.

K.J.Healey

I believe they refer to the single radar photo in the time sequence that has a NE direction line. Looks like simple doppler radar error to me. Its basically originating at the doppler station in the city and cuts for a few degrees along its scan path. Probably just a coloring error due to a reset or something.

There are also rings. Don't know what those could be other than coloum shaped clouds with majority moisture on the outside? remember weather doppler measures a lot of things, but im pretty sure metallic flying objects and wromholes aren't one of them.

PIT2

The weird things are those large rings appearing.
Apparently it was weird enough to make the newspaper:

http://www.softspotopening.com/Article.bmp

russ_watters

I'm not a meteorologist, but they look like thermals to me. Thermals are literally bubbles of warm air.

Evo

According to the article it's caused by birds. The meteorologist & his colleagues say they witness this about 3-4 times a year. What they thought was unusual was it was a bit early in the year for the birds to be migrating, but it did appear to be birds.

PIT2

So far weve got:

-birds (which according to the paper happens 3 or 4 times a year, but here its 5 times in 90 minutes - in the wrong season)
-thermals (anyone know how large these get? - I believe 45 miles is a bit large for a thermal(or for birds))
-nuclear bombs

Any other options?

Aether

I have studied thermals, and find russ_watters' suggestion to be an interesting one. Basically, warm air at the surface of the Earth will rise if/when the vertical temperature profile of the air above the surface is colder than about 4 deg. F/1000 ft.. Warmer than that, and you have a 'temperature inversion' which supresses thermals. The patern on the radar map could be consistent with a fast moving cold front descending from north to south across the area. It would be interesting to see the weather charts for this region at this time to see if such a cold front passed through.

Thermals can be any size. The whole Earth is continually involved with thermal convection on a global scale...

Global Scale Circulation of the Atmosphere: http://www.physicalgeography.net/fundamentals/7p.html

Garth

Coronal mass ejections hitting the Earth?

Garth

russ_watters

I'm not a big fan of the birds theory - a 45 mile circular formation would have to contain millions of birds. And it is a little big for a thermal, too, but when thunderstorms form, the cloud tops can really spread out. The 4th pic down here is probably on the order of about 20 miles in diameter. http://www.physicalgeography.net/fundamentals/7t.html

But then also, it's something like 5:00am, which is early for thunderstorm/thermal activity.

Ivan Seeking

Here is the weather data for Fort Wayne that day
http://weather.fortwayne.com/auto/fo...q_statename=NA

If it was cold it would be easier to explain. However, note that the temp dips to the day's low from 5 to 6 AM, and the wind goes to zero from 4 to 6AM. The event duration is from about 5:30 to 7:00, EST.

I have driven through those areas, much of which are mostly covered with corn fields, and there is a good deal of irrigating done. Perhaps this plays a role somehow...

Ivan Seeking

Something else is that the dew point is hovering just below the temp through those hours. A slight variation in either would result in saturation.

PIT2

On this page they show that plowed flieds create thermals:
http://www.aerospaceweb.org/question/nature/q0253.shtml

There are also things called 'ring vortices', but they are also not this big:
http://sodar.obninsk.org/Vortex/Vortex1e.htm

How about exploding meteors?

russ_watters

Far too slow (not to mention, no damage...) to be exploding meteors.