I’ve been saying this for a while, but it’s only recently that I’ve realized that someone has done statistical analysis on the subject and proven my point. It’s a long read, so here are some of the highlights.
The prize for the single most inconsistent forecast goes to Channel 5’s Devon Lucie who on Sunday, September 30th predicted a high temperature of 53 degrees for October 7th, and seven days later changed it to 84 degrees — a difference of 31 degrees! It turned out to be 81 that day.
A close second was Channel 4’s Mike Thompson’s initial prediction of 83 for October 15th, which he changed to 53 just two days later. It turned out to be 64 on the 15th.
The graph above shows that stations get their precipitation predictions correct about 85 percent of the time one day out and decline to about 73 percent seven days out.
On the surface, that would not seem too bad. But consider that if a meteorologist always predicted that it would never rain, they would be right 86.3 percent of the time. So if a viewer was looking for more certainty than just assuming it will not rain, a successful meteorologist would have to be better than 86.3 percent. Three of the forecasters were about 87 percent at one day out — a hair over the threshold for success. Other than that, no forecaster is ever better than just assuming it won’t rain.
And more. Check out the article.