Weather Watch: December 11: Electrical storms get sky-watchers excited

Electrical storms are an impressive sight. Photo / Brett Phibbs

Like last year, December marks a sudden shift in the weather pattern, bringing heat, humidity, rain and thunderstorms to the upper two-thirds of New Zealand.

While the changeable spring-like pattern slowly dies away, the sudden surge of tropical warmth, especially over the top half of the North Island, has been quite dramatic.

The main reason for the change is that highs are no longer tracking north and are now crossing central New Zealand. That has opened the floodgates to the sub-tropics.

Thunderstorms have been the main feature this week in both main islands.

"Thunder and lightning here in coastal Taranaki at 4am on Tuesday scared the calves on to half the farm and there's been 40mm of rain since last night," Shelly Bolland wrote on the WeatherWatch.co.nz Facebook page.

Other readers, spurred by nature's own energy, quickly started talking to one another.

Lisa Mckelvey: "Awesome lighting display."

Niki Hill: "Lisa, I'll be at your place soon, lol."

And following a severe thunderstorm warning for Hawke's Bay, Nicole Matthews wrote: "I want one 2. Stupid chch never gets thunder ... ask Hawkes Bay if they would trade some earthquakes for just one good thunderstorm."

Thunderstorms are exciting - and in some places, like America, they kill more people than any other severe weather, including hurricanes.

Like many readers, I love thunderstorms but have seen first hand how frightening one can be if it spawns a tornado.

Speaking of tornadoes, a funnel cloud formed near Hamilton this week. It didn't turn into a tornado - the cloud needs to touch the ground to do that - but it is a reminder that with severe summer thunderstorms comes the risk of tornadoes.

Many of us as kids were taught to open windows on the sheltered side of a house when a tornado moves in - but research these days shows that is the worst thing you can do. They move so fast that while you're busy worrying about windows, the storm may already be hitting your home. Stay away from windows and get into a closet or small space inside your house.

Luckily, tornadoes are few and far between in New Zealand, but tornado safety advice should be heeded.