March 19, 2013

Studying bubbles of air

WEATHER FORECASTING is an inexact science. Forecasters don’t often admit it, but few forecasts are accurate for more than three days ahead. And no wonder.

Weather is just great spheres of air, huge warm and cold bubbles hundreds or thousands of miles across, jostling fiercely against each other, moving up and down. Who knows where they might go next?

If you find yourself at the meeting point of two bubbles (what the experts call a front) you can expect some very interesting weather as they try to beat each other up.

Your barometer measures the atmospheric pressure inside these bubbles. High pressure means a good steady bubble and nice weather. Low pressure signifies a bad boisterous bubble and rotten weather.

So if your barometer is steady, you can expect tomorrow’s weather to be much more like today’s than anything else. If it’s falling, you can expect worse weather. The faster the fall, the sooner it will arrive. If the glass is rising, a good bubble has arrived and fine weather will follow.

You’ll find your barometer just as reliable as a weatherfax once you’ve learnt to interpret it, and a lot cheaper.

Incidentally, it’s the speed of the barometer’s rise or fall that determines how quickly and how drastically the weather will change.

Today’s Thought
To talk of the weather, it’s nothing but folly,
For when it rains on the hill, it shines in the valley.
—Denham, Proverbs

Tailpiece
Patience is most admirable when it’s in the driver behind you, but quite unacceptable when it’s in the driver in front.

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

1 comment:

Boathook Bald said...

Good post, and fully agree with your conclusion;
On a similar note, many years ago the first piece of fancy electronic equipment to be installed in the Harbour Pilots Office (where I was employed as a Cox'n) was a box which would give us all the current weather information. We all found it a lot easier, and more accurate, to look out of the window to see what was happening!