In the 1990s, I saw a lightning detector in an electronics magazine I bought when I was in New London CT for a couple of weeks. I did purchase it as it used both optical detection and rf detection.
On problem we had, and I discussed it with the designer, was the optical side detected lightning on sunny days. Well, the NASA scientist that designed it, mentioned the sun reflecting off the ice crystals in the upper atmosphere as the cause. I also told him that the next model should have some form of sensitivity adjustment and maybe the optical range should be looking up. We used it as an early warning for thunderstorms moving in from the west as we lived 40 minutes from the station. I ended up anding the rf and optic dry contacts to activate the alarm and then using a retriggerable monostable with a long time constant to keep it from counting EVERY ground strike and cloud to cloud strike.
Atmospheric noise, typically from lighting was about 60 dB/uV in the LF range, in my area of operation ... which included Las Cruces. We had a secondary station in the South Central U.S. Loran Chain at Las Cruces. When we first installed that detector, there were plenty of false alarms ... so I had a few productive calls with the designer.
Anyway, welcome aboard. Have fun.