A rapidly forming low in the Tasman Sea could become a “weather bomb” before the weekend according to WeatherWatch.co.nz.
The term “weather bomb” is often misused by media outlets to describe any stormy weather however it should only be used to describe a rapid deepening of a low pressure system.
“It's the weather equivalent of having a tyre blow out" says head weather analyst Philip Duncan. "The air pressure plummets and conditions quickly become unstable".
Weather bombs in New Zealand tend to cause isolated but severe damage.
A weather bomb in Patea, South Taranaki, back in March caused extensive damage as hurricane force winds blew out roofs, walls and toppled trees.
Mr Duncan says the chances of this low becoming a “weather bomb” are fairly high at this stage. "The models we're looking at show the air pressure dropping from around 1000hPa on Thursday evening to 976hPa on Friday morning, possibly lower".
The low is expected to generate big seas on the western coastline, torrential rain for the West Coast and severe west to north west gales for eastern and central New Zealand.
"We still have to wait another day or two to confirm but no matter how you look at it, it seems likely a nasty low will develop in the Tasman Sea overnight Thursday and into Friday - then weaken across the weekend as it passes over New Zealand".
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