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Weird doppler-radar images

  1. Dec 25, 2005 #1
  2. jcsd
  3. Dec 25, 2005 #2
    Looks like it originated from Indianapolis. I have one word: NASCAR
     
  4. Dec 25, 2005 #3
    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
     
  5. Dec 25, 2005 #4

    russ_watters

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    I don't see anything weird in that gif - to what are you referring?
     
  6. Dec 25, 2005 #5

    Evo

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    Thanks, I was wondering if I was the only one that wasn't seeing things.
     
  7. Dec 25, 2005 #6
    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.
     
  8. Dec 26, 2005 #7
  9. Dec 26, 2005 #8

    russ_watters

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    I'm not a meteorologist, but they look like thermals to me. Thermals are literally bubbles of warm air.
     
  10. Dec 26, 2005 #9

    Evo

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    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.
     
  11. Dec 26, 2005 #10
    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 :biggrin:

    Any other options?
     
  12. Dec 26, 2005 #11

    Aether

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    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
     
    Last edited: Dec 26, 2005
  13. Dec 26, 2005 #12

    Garth

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    Coronal mass ejections hitting the Earth?

    Garth
     
  14. Dec 26, 2005 #13

    russ_watters

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    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.
     
  15. Dec 26, 2005 #14

    Ivan Seeking

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    Here is the weather data for Fort Wayne that day
    http://weather.fortwayne.com/auto/f...tml?req_city=NA&req_state=NA&req_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...
     
    Last edited: Dec 26, 2005
  16. Dec 26, 2005 #15

    Ivan Seeking

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    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.
     
  17. Dec 27, 2005 #16
  18. Dec 27, 2005 #17

    russ_watters

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    Far too slow (not to mention, no damage...) to be exploding meteors.
     
  19. Dec 27, 2005 #18

    Aether

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    Last edited: Dec 27, 2005
  20. Dec 28, 2005 #19

    Aether

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    I have also (e.g., in addition to the data from the Indianapolis, IN radar station) downloaded (from the NCDC) the archived NEXRAD Level-II radar data for the time period in question which was recorded from Cincinnati, OH. Since the field of view for both of these radar stations overlap in the area where the anomalies occur, this might help sort out what went on there.

    How much do you want to bet that I can't make Mickey Mouse appear (on a NEXRAD radar image) in the clouds over Evansville? :biggrin:
     
    Last edited: Dec 28, 2005
  21. Dec 28, 2005 #20

    Aether

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    Wow! There appears to be something really going on within the atmosphere here.
    Here is the Indianapolis, IN (KIND) NEXRAD (velocity) image for 19960802_105737:
    And here is the Cincinnati, OH (KILN) NEXRAD (velocity) image for 19960802_105702:

    The concentric rings on the display are 50km apart.
     
    Last edited: Aug 30, 2006
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