Is binning the lightning distances really the best way to display that info?

That’s right. A “1” translates to “overhead” according to the technical data sheet provided by the Franklin sensor manufacturer. In our experience, we’ve found the values reported by the Franklin to contain quite a bit of uncertainty. That’s why we report the “1” value as “0-5 km” in the apps. Reporting anything else would be inconsistent with the data we’ve seen. We try to err on the side of caution.

Note that we have improved the ability to calibrate and fine-tune the Franklin sensor in the Tempest device and we will likely need to re-evaluate how we report lightning (for the better) in the forthcoming Tempest apps