Weather Watch: Thundering on about very little indeed

Plenty of rain but where was the thunder? Photo / Brett Phibbs

"Well that would have to be the biggest non-event in Auckland's history," wrote Mel Baker on WeatherWatch's Facebook page last Sunday. This comment came after a day of thunderstorm warnings and watches and not one single rumble of thunder was heard in Auckland.

Compared to many other countries, we don't really have a lot of thunder activity in our populated places, the bulk occurs on the West Coast.

There is something about thunderstorms that stirs up adrenalin in us: either it's the excitement of hearing booms and seeing brilliant flashes or it's the absolute fear of one hitting.

The problems last Sunday were:

a) The forecasters were pretty inaccurate.

b) The public don't understand what the difference is between a watch and a warning.

A severe thunderstorm watch means we have all the ingredients for thunderstorm activity but no immediate threat. A warning is when a severe thunderstorm is being tracked on radar and the government forecaster warns us of them.

However, the watches and outlooks are incredibly widespread. It's a bit like saying "there could be a heavy shower today ... in the North Island" as opposed to "in Hamilton". These outlooks cover hundreds of kilometres and sometimes, like Sunday, much of the country ... but it doesn't mean there will be much thunder.

With regards to the thunderstorms' failure to arrive, Kay Bason told us: "Love it, thanks. I don't want a tornado to whoosh me away - whoops, there goes nana!"

And Andrew Blackie wrote: "We only get them when WeatherWatch and MetService don't forecast them."

As to why MetService warned of a "high risk" for thunderstorms, I can't answer that but what I can say is the problem is thunderstorms are tricky to forecast in New Zealand.

We don't have the luxury of a great land expanse like America does, where you can see them coming from some way off. But we can certainly predict when we have the right ingredients.