Accurate forecasting

[Jeff S]

Just read this. What I would like to know is how they can forecast weather so far in advance. After all they can't seem to get it right one day in advance. Or here I'd love to be a meteorologist. Even if they are wrong they are right. Bring on the freeze, the grayling love it frosty

 

Freezing Weather 'Here by Monday'

 

The cold spell is expected to bring snow

 

One of the coldest winters in recent memory is about to hit Britain, according to weather experts who correctly predicted this summer's washout.

 

The first cold snap will arrive on Monday, with regular cold fronts sweeping across the country until Christmas, according to forecasters at Metcheck.com.

 

Further prolonged bitter spells are expected to follow in the New Year.

 

Andrew Bond, senior forecaster for the group, said: "From what we are predicting, Britain could see its coldest winter of the century so far.

 

"It is time to ditch the wellies for woollies. This winter will be a lot more cold and less wet than previous winters. The cold snap next week is nature giving us a taste of what is to come in the next few months."

 

He added: "We are confident that we will see a higher than average frequency of northerly weather types, bringing not just colder weather but a more frequent snowfall than we have experienced in recent years."

 

Mr Bond predicted bitterly cold winds in the South and snowfall in the North and said there would then be a very cold spell between November 22 and 27.

 

Other forecasters are more cautious in their predictions for winter.

 

Daniel Adamson, senior meteorologist for the PA WeatherCentre, said: "We can't predict more than 10 days ahead with any accuracy, and there is nothing to suggest that it's going to be exceptionally cold at all."

 

Oh there it is in the fine print.

 

[ 13. October 2004, 12:03 PM: Message edited by: Jeff S ]

[darrell.cook]

Us "Brits" like to have a moan, governments and weather forcasters can always look out But - Weather forcasting really is cr*p don't you agree ?

I studied the forecast for last Saturday, because I was fishing, The Tuesday forecast changed completely by Friday and when Saturday came it bore no resembelance to either !!

[Jeff S]

I have noticed that British weather usually is forcasted sunshine with possible rain or gray with occasional sunshine. How can you go wrong with that?

[Paul_D]

What always baffles me is that the 7 day forecast given on the BBC's Country File program is usually spot on but the BBC's day to day forecasts given by the same people are often very inacurate. :confused:

[Guest gus angus]

Because I do all my fishing from a boat, I watch the weather forcasts like hawk, I use metcheck, the met office, online weather and study the charts from wetterzentral (german site) between the three I usually know with a fair degree of confidence if we will be going two days before the event, take all three and get an average you won't be far wrong,and I don't listen to the ones on the telly, they don't even look out the window. having said all that, should I have to? with their budgets and technology we should have spot on forcasts every day

[Jim Roper]

Someone will blame it on global warming!

[Steve Burke]

There's major difference between how short term and long term forecasting is done.

 

Short term forecasting takes the current weather situation and works out how it will change. Even in the UK where weather is notoriously difficult to predict, these short term forecasts are usually fairly accurate up to about 5 days ahead - certainly enough for me to plan which day or days to go fishing.

 

Long term forecasting looks at such things as sea temperatute, whether there's an El Nino etc and predicts whether it'll be hotter/colder, drier/wetter than average. These are much less accurate than short term forecasts. In fact as a result, many forecasting companies won't stick their necks out and don't issue long range forecasts.

 

I suspect that the PA Weather Centre don't issue such forecasts. They do the forecasts on ITV's Teletext and I have to say I'm not very impressed with their accuracy in East Kent.

 

I have a great deal more faith in MetCheck, who I reckon have the best weasther site on the internet. I haven't seen their long range forecast in detail as I gather it's not being released to other than their fee-paying premium customers until Monday. However, as with all long range forecasts, I'll be taking it with a pinch of salt!

[Leon Roskilly]

To forecast accurately, you need to track just about every parcel of air, and sea current, and every interaction between them and what's arriving from the sun, and the movement of every cloud.

 

In short there are just too many parameters to track to ever be able to do it with a high degree of certain accuracy, no matter how much you spend.

 

But fortunately systems can be tracked, and their behaviour is predictable, but only to a certain extent.

 

(Until a butterfly unexpectedly flaps it's wings!)

 

Sometimes with more certainty than at other times.

 

Basically, you build a model and run it forward.

 

Then you introduce some slight changes and run it forward again, and do that several times.

 

If each run comes out with broadly the same answer, the situation is 'non-chaotic' and you can be reasonably confident of a general forecast, maybe up to 10 days ahead.

 

Other times, those small changes will result in totally different forecasts in the next 24 hours.

 

In which case the weather situation is 'chaotic' and there can be very little confidence in the general forecast

 

Now, even when there is confidence in the general forecast, locally things may be very different to what's happening just a few miles away.

 

A 'slight risk' of rain will be cursed by the angler who forgot his brolly and was drenched in a downpour, whilst a guy a few miles away who enjoyed hot sunshine all day is cursing the weatherman for persuading him to carry al that heavy wet gear!

 

Learn a bit about what drives the weather, learn how local conditions affect that (we have a ridge nearby where the weather can be totally different all day, depending on wind direction and which side of the ridge you are fishing!), and take into account what the weather people are saying, and why they are saying it.

 

Then do your own forecast (and still get wet!)

 

Tight Lines - leon

[Jim Roper]

About seven year ago, I was doing a DTP course where the lecturer had been a meteorologist in the Navy.

At the beginning of December has asked how he could put a bet on it being a 'white Xmas', as he had never bet in his life.

He got it right!

Don't know if he got his bet on or not!

All I remember is that he left before we finished the course to teach weather forecasting to officers in the Saudi airforce.

 

I think a lot of forecasting is done by remembering what happened the last time all the variables, thousands of them, were like they are at the moment.

A bit like chess, I suppose!

[Guest gus angus]

must agree with Steve on METCHECK they are very good in comparison with the rest.