Radar Question

[Danny Neal]

I posted it as an attachment. I saw this on the Lincoln radar and now the Chicago radar. Right near Preston Heights. Is there something specifically causing this high reflectivity(Smoke, factory exhaust, etc) or is it just ground clutter?

 

[Jarrod Cook]

Was that area of high reflectivity moving at all? Or was it stationary?

Most likely is ground clutter though, consiering where you're looking

 

[rdale]

That's ground clutter - you can tell by looping and/or looking at higher elevations.

 

[Danny Neal]

I know its clutter, but was it specifically caused by anything? It moved down the road and then moved back. I am familiar with with "speckled" clutter but seeing it move in a line and having that high reflectivity was weird. I know sometimes you see airplanes and perhaps cars but those are such a low reflectivity that it's almost impossible to discern. Oh well. It is cleared up now.

 

[rdale]

Could have been related to the showers downrange and it confusing the radar's clutter suppression.

 

[Mike Smith]

I am sure it is not a normal clutter pattern. It looks like some sort of processing problem or test pattern.

 

[rdale]

That's not a test pattern, it happened while strong storms were passing just south of the radarsite, so my guess is the clutter suppression algorithm wasn't handling it perfect. Notice he is VERY tightly zoomed in.

 

[Rob Herman]

Might be traffic on State Route 53. Does look like there's a hill coming up out of the river valley that would elevate the vehicles. Try looking at unsmoothed velocity data.

 

[Bryan Howell]

I'll second the vote for cars on 53. When roads line up with the radials of a radar (like it does in this case) and atmospheric conditions are just right (which they were in this case) you can actually see traffic on roadways. Usually they show up better on the radial velocity product. I've seen it on KLOT and KDMX before that I can remember off the top of my head. I have a screen shot of KDMX where you can see returns along both I-80 and I-35. I used to have it on my flash drive, but can't seem to find it. I'll look on my computer when I get home and post it up here. It's pretty neat!

 

[Joe Nield]

Chicago had an example of the automobile returns phenomenon on their website last year. You can check it out in their news archive HERE.

They show only velocity images on their story, though. It would be interesting to see if there were spikes in the velocity data along that area at that time frame.

 

[Adam Lucio]

I see that same spot of high reflectivity when I look at KLOT all the time.

I always thought it was a tall building or other structure and never payed much attention to it.

 

[rdale]

That line has been there for days now, so you can look at it whenever you want and see velocity & SW. You can also see reflect/velocity on I-80 in the bend southwest of the radar.

 

[Bryan Howell]

The bright greens and reds along I-35 northeast of the radar and along I-80 east of the radar are cars and trucks. This was after a line of storms went through, I believe.