Peter and Lynne Hill, of Mosgiel, asks :-

Is there a specific time of year when NZ is more vulnerable to lightning strikes?

Craig Rodger, an atmospheric physicist at the University of Otago, responded.

Since August 2000 lightning activity in New Zealand has been monitored by the New Zealand Lightning Detection Network (NZLDN) which is operated by the MetService, and owned by Transpower. It is designed to detect cloud to ground lightning, which are the most hazardous to people and technology.

From the networks start date through to the end of 2016 the NZLDN has detected slightly more than 3 million lightning strokes.

While that sounds like a lot of lightning discharges, it equates to one lightning stroke in the New Zealand region roughly every 167 seconds (i.e., slightly less than 3 minutes) - in comparison, one average there are 44 lightning flashes across the globe ever second! So only one cloud to ground lightning discharge in every 7348 occurs in New Zealand - the remainder are elsewhere in the world. Lightning is comparatively rare in New Zealand.

NZLDN data allows us to directly answer your question. In New Zealand lightning is most common at the height of summer, in December and January. One quarter of the lightning in New Zealand occurs in those two months.

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