Why cant we predict the weather in the UK?

Question

I have been checking the weather forecasts on two occasions for a week daily over the last two months. I found that the forecast changed pretty much daily. From Sunny, to cloudy to heavy showers back to overcast and so forth.

I am just curious why with all our technology blah blah blah we are still not able to predict the weather accurately a few days in advance. I can undrstand why long term forecasts are difficult but two days in advance it says sunshine and on the day it rains. Whats up with that?

Answer 1

we can predict the weather

Answer 2

Hi Jack Flow.  It is a very interesting question.  I am addicted to the BBC weather website - sad I know.  Certainly they have got it right for Leeds today but yesterday it said rain and it was sunny and very windy. I guess that the weather can be one thing and then change quite quickly.  Sorry I can't offer a scientific answer.

Answer 3

read up on the term 'chaos'... it basically says that just a tiny difference in starting conditions will ultimately make a large difference in the outcome (attractor)

weather stations can't accurately measure conditions at every point in the world, so if these (non-accurate) starting conditions are plugged into super-computers, the outcome (attractor) will ultimately be differenct from real life

Also look up the 'butterfly effect', that has a bit of significance as well.

*d**n, just seen that the person above me said exactly the same thing! oops*

Answer 4

Forecasts for the UK can be a little more difficult than other regions of the world for a number of reasons.  Mainly, it stems from the chaotic nature of the atmosphere, especially as it relates to the fast moving systems in the mid-latitudes.  You see, the UK can see multiple types of weather all in a 24 hours period as strong low pressure systems come onshore from the north Atlantic and streak across the British Isles.  The weather systems over the ocean are often not well resolved by models with regards to rapid development and/or a quick drop in pressure  (Evidence seen last year when no models could predict the 2 large hurricanes rapid deepening over the Carib)

The Met Office also mentions this about using models to predict weather:

Despite the vast improvements in NWP models over the years, large errors may still occur even over relatively short forecast ranges. This is due to the chaotic nature of the atmosphere which means that a small error in the initial conditions may lead to a large error in the subsequent forecast, the so called 'butterfly effect'. Because we can never know the exact truth of the initial conditions, there will always be a degree of uncertainty in the resulting forecast

Answer 5

I don't have an answer either, but I find it fascinating as a Brit that over here in Germany people do rely on weather forecasts, and most of the time it actually works.  Only this morning my husband said about someone who's coming round at 6 that they'll be sitting outside because "there's only an 8 per cent chance of rain".

Different planets.