A site that compares weather forecasts to actual weather?

June 7, 2011 1:06 PM

Is there a site that compares actual weather records (recorded temperature, precipitation, etc.) with various online weather forecasts to show which forecasts are more reliable?

Preferably, it would always show the last n days, not just a sample of historical data. I don't want to know how accurate site X used to be a couple of years ago, but how accurate site X is now in comparison to sites Y and Z now.

posted by pracowity to Science & Nature (3 answers total)

Check out Weatherspark. It graphs actual weather data historically, and you can compare several services (NOAA, WWO, etc).
posted by sprocket87 at 1:24 PM on June 7, 2011

I can't provide you with a website, but anecdotally, I remember attending a seminar a few years ago in college where the speaker, in anticipation of giving the seminar, tracked all the Minneapolis news sources (TV, newspaper, etc.) for several months to compare the extended forecast to the actual weather that happened on each day. Although the weather reports differed, they were all about equally wrong more than 3 days out. In fact, as my memory serves, most actually did worse than random chance at predicting the weather. The conclusion was that anything outside the 3-day forecast window is nothing more than a novelty.

This doesn't get you any closer to an answer, but if such a website doesn't already exist, someone should make one....
posted by wondercow at 8:53 PM on June 7, 2011 [1 favorite]

Oh, for what it's worth, here is the abstract for that seminar. The speaker was Jim Hansen from MIT. If you emailed him, I wouldn't be surprised at all if he had the answer to your question already worked out. He was a really engaging speaker (I still remember his talk 7 years later now) and gave the impression of being pretty approachable.
posted by wondercow at 9:04 PM on June 7, 2011