309,959,570 Lightning Strikes in Six Months
UPDATE: As Mike Smith pointed out: "the high number of strikes in the Upper Mississippi Valley... they had a much worse than normal tornado season in the area and the amount of lightning corresponds to it."
Vaisala, the original lightning detection company that I have profiled before, sent this map showing nearly 310 million lightning strikes on Earth (specifically 309,959,570, they tell me) in the last six months via their Global Lightning Dataset:
The map looks similar to those from NASA's satellite estimates, but because it's only 6 months of data, it doesn't line up perfectly, and these are ground-based, not satellite sensors.
Here's a zoom of the United States. The map shows the density of lightning strikes, with the maximum purple in the Missouri area being 32 strikes per 20 kilometers. You can easily see how mountains (the Rockies & Appalachians) stand out because they have very little lightning. This is because air moving up the mountains from the west drys out, and because the geography disrupts the storms' circulations.
