Meteorologists: Please Consider Sidelobe Contamination in Doppler Data...

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...and stop issuing tornado warnings on them. 

We have discussed, multiple times, the deteriorating trend in National Weather Service tornado warning statistics. One thing that could be done immediately to lower the unacceptably high "false alarm rate" would be for NWS meteorologists to learn about "sidelobe contamination" (outstanding, highly useful paper, here) and cease issuing warnings on it. 

Here is an example from early this evening where the warning should probably have not been issued. Please click to enlarge. 
At upper left is a weak echo region ahead of a pendant echo. By itself, it is an area worthy of examination. However, the rotation is not geographically coincident with the pendant (upper right) which shouts "side lobe." The blue circle was drawn in the same location in all four panels. Further, the spectrum width (lower left) is near zero and there is no correlation coefficient lowering (lower right). When one combines the unimpressive radar presentation that with no reports of tornadoes in the area, this is a tornado warning that probably should not have been issued and it certainly should not have been continued.

A more egregious example was about 20 minutes ago. In this tornado warning the rotation is, metaphorically, in the middle of nowhere. 
There is no reflectivity associated with the rotation. This is a tilted supercell and the rotation aloft is being detected by the radar's sidelobes. 

A friend just posted on Twitter that there have been 17 tornado warnings issued this evening but, so far, just three reports of tornadoes. The sidelobe issue accounts in large part for the discrepancy.

What should all of these look like in a valid tornado warning? See below from December 10, 2011.
Everything is in the same geographic area. 

While on the topic, could we stop issuing tornado warnings that look like this?
If the adjacent office will not fill in the middle, perhaps the tornado warning should not be continued. 

Attention to both of these issues will lower the false alarm rate and improve the credibility of the tornado warning system. 

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