Calling all weather experts!

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I'm off on a 2 week bike trip on Friday around central Europe. Spanning over the following countries.

France, Italy, Switzerland, Austria, Germany, Belgium and the Netherlands.

Highlights are a 5 day trip over the alps staring in Marsielle and finishing in central Austria.

Now, as far as I can see, the first weekend (this weekend coming) looks to be wet... None stop. My question is, can anyone give me a rough idea if the next 2 weeks are going to be cack as well? I really need to make a choice of whether to do the Alps or head down south into Spain or Italy...
 
It will be average temperatures with average precipitation and average amounts of sun.
And I'm being serious here.

Reasonably accurate forecasts barely extend to 5 days with any significant predicative value, and in unstable conditions it can be much less. Even then detailed forecasts are only possible with around 48hrs. Small trends can be observed over the 10 day line but these can have wild swings a few days out.


What you can't do is look at a single forecast and get any significant information for 2 weeks out. What you can do is repeatedly observe multiple different models outputs, from different forecast models, and examine the ensemble runs wherever possible. And then repeat this every 6 hours with the new runs. If you do this for a few days then you can start to see some more stable trends on the longer range model run to allow you to draw general conclusions, e.g. a cooler sower weather next week, or 60% chance of high pressure sunnier weather. You can't derive any specifics.

Ultimately as the length of forecast time increases then then the forecast predictive value rapidly declines to zero and the best forecast is simply the long term climatic average for the time of year. So As I said at the top, if you want to know the weather in a couple of weeks time just look up the average weather for early September.
 
Over the span of the next 4 days, the forecast for the routes I'll be making seem to be 'average'. I think once I get to Austria, I will be able to make a choice. Jump off the Alps and head to a warmer southern Italy or crack on and stick to it.
 
3 days is about the max i find forecasts are reasonably accurate. I certainly wouldn't change a cycling trip plan based off a long range forecast.

Big weather events like hurricane cristobal can give an indication further out. I suspect it's likely to be damp all across most of north-west Europe the next 5-10 days as it's side effects pass though.
 
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Vtec9k said:
3 days is about the max i find forecasts are reasonably accurate. I certainly wouldn't change a cycling trip plan based off a long range forecast.

Big weather events like hurricane cristobal can give an indication further out. I suspect it's likely to be damp all across most of north-west Europe the next 5-10 days as it's side effects pass though.
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Motorcycle. So I will be slightly better shielded from the elements lol.
 
Do you think it would be worth skipping the Alps and going to Southern Spain? Is there any fun clubbing islands down there?
 
Just got back from a 6 day trek in the French Alps, and the weather wasn't so great. Two days of sun and four days of rain we even had some light snow one evening. We would get a weather forecast for the next day each evening in whichever hut we were staying in and even that wasn't very accurate the rain never seemed to clear up even if it was forecast to do so. All the locals were pretty miffed they had some of the most rain ever recorded in July and August was shaping up to be near enough the same. Not sure what its like now but I'd pack the rain gear :(
 
Looking like more of the same at the moment - chains of low pressure (bringing rain) interspersed with brief periods of warmer drier weather.
 
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Rroff said:
Typical - when it looked like low pressure dominance for awhile its now looking like the next couple of weeks could be warm to very warm before longer term cooling sets in. (though sill made sense to hit the south first).
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See below

D.P. said:
It will be average temperatures with average precipitation and average amounts of sun.
And I'm being serious here.

Reasonably accurate forecasts barely extend to 5 days with any significant predicative value, and in unstable conditions it can be much less. Even then detailed forecasts are only possible with around 48hrs. Small trends can be observed over the 10 day line but these can have wild swings a few days out.


What you can't do is look at a single forecast and get any significant information for 2 weeks out. What you can do is repeatedly observe multiple different models outputs, from different forecast models, and examine the ensemble runs wherever possible. And then repeat this every 6 hours with the new runs. If you do this for a few days then you can start to see some more stable trends on the longer range model run to allow you to draw general conclusions, e.g. a cooler sower weather next week, or 60% chance of high pressure sunnier weather. You can't derive any specifics.

Ultimately as the length of forecast time increases then then the forecast predictive value rapidly declines to zero and the best forecast is simply the long term climatic average for the time of year. So As I said at the top, if you want to know the weather in a couple of weeks time just look up the average weather for early September.
Click to expand...
Any forecast longer than a couple of days is useless, your thinking that "its now looking like the next couple of weeks could be warm to very warm before longer term cooling sets in" is flawed.
 
Hence the use of "looking like" and "could", just typical that it looked as predictable as it possibly could be for a long chain of low pressure and only a few days later completely changed.
 
the met office can not get the weather forecast right 12hrs in advance sometimes, and you want weeks ahead lol
 
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