How far ahead in the future can modern weather forecasting reliably predict the weather?

Question

I want to know how accurate weather prediction systems are, how many days can people accurately forecast the weather, and the percentages in general of their accuracy.

Answer 1

Based on forecast scores and experience, about 2 to 5 days. Some local locations during certain parts of the year, you may be able to do well up to 5 to 7 days.

Some people who had the same question as you, did their own "study". But one must note that some of these studies do not follow some of the strict rules and guidelines that are required for a more accurate results. Here are some links that you may want to look at.

http://216.109.125.130/search/cache?ei=UTF-8&p=accuracy+forecast+temperature+scores++noaa&fr=yie7c&u=www.omninerd.com/2007/02/08/articles/69&w=accuracy+forecast+temperature+scores+score+noaa&d=Zliv2-rnO2JO&icp=1&.intl=us

http://www.forecastadvisor.com/blog/

http://pajk.arh.noaa.gov/info/articles/survey/accuracy.htm

Answer 2

Although most TV stations give 7 day forecasts, they are highly unreliable after 3 days. There are too many things that can effect the weather and make it change for any forecast to be accurate any longer than 3 days. In fact, most pilots check it several times a day in order to not have problems while flying. This is why most forecasters never say there is a 100% chance of anything. They know they can't be completely right and they always leave themselves some room to say that they weren't completely wrong, since they didn't say it was a 100% chance when they made the forecast.

Answer 3

Too many variables to answer your question precisely. Depends on the location, and the type of weather you are predicting. A forecast of sunny weather can often be predicted a week in advance. A prediction of 100% chance of rain in 24 hours can only have an accuracy of 50%. The range is anywhere in between.

Answer 4

My first comment is that I don't really believe you are asking a question, but making a statement. YA is intended for actual questions. Otherwise I think you're making a good point, that most people seem not to understand. I think they also don't understand how much weather forecasts have improved in the last 20 years. EDIT: One answerer said: "Because according to the AGW crowd, you don't need to know all of the boundary conditions. You just need to know that CO2 is driving the warming and thus your models are perfect. Or at least that is what I seem to see the consensus as doing. "If you disagree with the AGW crowd then you are an outcast." I don't understand how people that don't believe in AGW expect to convince other people of their beliefs by lying. No one has EVER claimed that the models are perfect, or that boundary conditions are not needed. Perhaps it is only the liars that become outcasts.

Answer 5

Excellent question. It is addressed in a popular book by James Gleick called "Chaos - Making a New Science" which you can probably pick up at your nearest library. The maximum practical limit appears to be around 14 days as first studied by Dr. Edward Lorenz. The reasons for this limitation are explained in Gleick's book.

Answer 6

i don't think weathermen predict very well where i live. but i would say two days only. although they try to predict up to 8 days ahead and they never seem to be right....they try to guess way to far ahead when they can barely get the next day right.

Answer 7

3 days but you could formalise pattens up to 3 weeks.

Answer 8

7days a week

Answer 9

half hour...... and they are usually right 10% of the time.

Answer 10

not sure