Wednesday, January 06, 2010

Weather Predictions- A Hypothesis

For all the talk of snow bringing the country to a standstill, the actual amount that has settled doesn't seem that much to me, despite the dire warnings from the meteorologists.

Back in 1987 Michael Fish famously dismissed the possibility of heavy storms- right before the heaviest storms in living memory devastated southern England- and has held a degree of notoriety for this erroneous prediction ever since.

No one ever pays a price for an excessively scary prediction, think of the Y2K experts, but failing to spot a problem earns an unwanted place in folk memory. Hence weather forecasters are more likely to overstate the severity of the weather than to understate it.


Mark said...

BBC News in particular likes to indulge in 'bad weather porn'.

The usual MO of the Beeb in these circumstances is to-

1.Pick up on a reading from a particular site (Odiham in Hants is the current example- which may indeed have actually recorded it's heaviest snowfall since the winter of discontent in 1979).

2 Then universalise this one measure of bad weather to claim that this is the worst snow/ cold spell for 30 years.

Anyone with a good memory, or decent reference books, knows these claims are pure bunkum. In London the snow was heavier just 11 months ago, and across southern England there were cold spells in 1981/82, 1985, 1986, & 1987 & 1991 which were harsher than anything we've had so far this winter.

Isn't the licence fee wonderful ?

Matthew said...

I'm always surprised how localised snowfalls are - my North London street is about 2.54cm thicker than the one a block south (facing same direction).

But yes, much 'worse' 11 months ago. I suppose it might still get worse if the forecasts are right and there's four more days to come.

banned said...

Had the first real snow for 10 years yesterday (ie can make full sized snowpersons instead of token ones with glorified frost) and the heaviest since 1981.
Happily the snowballing community had relieved my car of most of its snow covering.
Beeb local radio spent all day warning us off the roads unless our journey was "absolutly essential", schools closed, 44% of people failed to turn up for work ( fake stat ?), hardly any buses.
Load of b*ll*x. I was driving around the city all day and did a couple of visits to nearby towns with no problem at all.

It is now 04:45am, I just checked my car, no overnight frost or further snow.

Wow, was that it?

JuliaM said...

On Monday, we were promised 'the coldest weather for a decade'. Then, on Tuesday, it was declared 'the coldest weather for 20 years'.

Yesterday, we were back to 'the coldest weather for a decade' again. And that was on the same channel!

Do they think we don't note these things?

Matthew said...

That's a good point though. The difference between now and 11 months ago is that it is much colder, -5 degrees here in North London. So I guess the fallen snow isn't going anywhere.

Driving conditions here are dangerous - I took this photograph walking home last night from the tube station of a bus crash and the cars weren't doing much better

Matthew said...

Julia - on those statements it doesn't neeed a large forecast error to make them true. Say in 1999 it was -5.2, and in 1989 it reached -5.4, and they were forecasting -5.3, but we only got -5.1. Then the expectation of the coldest temperatures in 20 years turned out to be only in 10 years.

James Higham said...

With the new global cooling, we should much more of this? That would be great.

PJH said...

I find it mildly amusing that all this news of snow-fall only takes up large swathes of news time only when it happens in the south (notably in the south-east) and it happens even when the snow falls in moderation.

We've had snow on the ground since before Christmas in the North-east, and we've probably had 4+ inches of the stuff in the past few days.

Could (ala-Mock-the-Week) this be because we only have one news correspondent for the whole of the north and all the rest are based in London?


Ross said...

Mark- you're right about the MO, although ITV local news bulletins do the same.

PJH- That's true, events become less newsworthy the further they occur from London.

Malthebof said...

I think that the Met Office has become part of the drama department at the BBC. Thus all weather forecasts are over dramatised and the language used by the forecasters is very subjective