Weather warning: brace for a deluge of words

19:05, Jun 22 2013

It was a "once-in-50-year storm", it was "the most snow in a generation", it was the "strongest wind for years". Was it perhaps also "the most overblown weather language in a lifetime"?

Days before the first snowflake hit the country last week, there were already reports of the magnitude of the coming storm - and the hyperbole began falling as heavy and long as the forecast rain. head weather analyst Philip Duncan admitted the language of weather was a curious thing, and the public could be bombarded with grandiose descriptions of weather that in reality was not significantly worse than it had been in previous years.

For instance, he said, last week's storm was similar to that which hit in August 2011.

When there were reports of a "once in 100-year flood" happening in consecutive years, he did some digging to find out how that could be the case.

"It's a statistical calculation - it's one of those funny things," Duncan said.


Often when the power of a storm was stated, meteorologists would use the statistical likelihood of it repeating rather than measuring it against other weather events over the years.

MetService spokeswoman Jacqui Bridges said they would only make comparisons with the past when the storm had gone, and even then it was difficult to make sweeping statements.

Last week, some people compared Wellington's wild weather to that at the time of the Wahine disaster 45 years ago, but while waves were a similar height, the winds were not as strong.

Bridges said most of the "worst storm since . . ." quotes came from residents in affected areas, relying on their memories rather than scientific equipment.

Duncan, who set up WeatherWatch in 2005, said "emotive language slipped out" in the early days.

Bridges said the key was to get the correct information to people without embellishments.

"It's important we don't cry wolf," she said.

Duncan agreed it was important to focus on language and erring on the side of conservatism was always safest.

Sunday Star Times