Bottle-necks

Our weather in New Zealand is greatly modified by the shape of the land. There are many parts of the country where the air is channeled through gaps in the terrain, and I thought I would write a little about this. Especially since it relates to the thread of my earlier posts on wind.

The Thunderstorm in History

One of the pleasures of reading history is coming across stories about the weather. Thunderstorms often figure in these. One of the most dramatic examples was recorded in the sixth century AD, by Gregory, Bishop of Tours, in his Historia Francorum (The History of the Franks).

How Lows and Highs move

In my blog post about winds aloft there is a loop of satellite images for a week in winter 2008.  It shows that the big cloud features in the mid-latitudes typically travel from west to east. In other words, the features you see on weather maps affecting New Zealand have usually started out roughly in the area of southern Australia.

The mid-July northern low

On the night of 17th July and early on the 18th, New Zealand was affected by a fast-moving and rapidly deepening depression originating in the north Tasman Sea. Sustained southwesterly winds of more than 60 knots were recorded in Colville Channel as the low passed by. Severe Weather Warnings were issued for wind in Coromandel/Great Barrier Island and rain in the eastern North Island.

Year 12 Maths

Part of my job as a teacher of meteorology is to go to NZ universities looking for future meteorologists. It breaks my heart when, sometimes I meet a person with a genuine passion for the weather who would love to work for us as a meteorologist, but just can't cope with the required maths. Unfortunately for them, professional meteorologists need to have some university maths under their belts. And this requirement isn't just a local thing - it also comes from the World Meteorological Organisation of which we are a member nation.

PINE POLLEN IN THE PUDDLE

When I was biking to work this morning I noticed prolific amounts of pine pollen in the puddles around Westhaven.

Blooming daffodils and wayward winds.

I find it fascinating that there is so much pattern in our weather, and I find it frustrating when, sometimes, chaotically, one of them behaves slightly differently, as in this case producing wayward winds for Auckland.

The Great Northwesterly Storm of August 1975

If you were in New Zealand in the mid '70s you may remember a particularly strong wind-storm that devastated many parts of the eastern South Island. It struck on 1 August 1975, doing a huge amount of damage to pine trees in the Eyrewell and Balmoral forests in particular.

To give you an idea of the power of this storm, some of the peak recorded winds and gusts were: