Where does Accuweather get its data?

August 19, 2007 1:35 PM

To what degree to private weather forecasting companies (like Accuweather) rely on US government data in creating their forecasts?

I know that the the USG, primarily through NOAA and NWS, collects meteorological information via weather buoys, balloons, observation stations, radar, satellites, etc, to use for creating forecasts (and other stuff). Do private companies get access to this relatively raw data for their own models & forecasts?

I am not asking about the use of NWS forecast products necessarily (which I figure are available to the public). I assume that these private companies do more than just rewrite NWS forecasts, and generate their own forecasts based on their own modeling--if so, where is the data coming from?

posted by Brian James to Science & Nature (9 answers total)

interesting question, but i would assume that is proprietary information.
posted by thinkingwoman at 1:46 PM on August 19, 2007

Well, we used to subscribe to AccuWeather at the University. I guess I can't say for certain, but I got the impression that they we not so much rewriting the government forecasts as they were plugging their data into their own formulae to create their own forecasts. I recall, at times, calling them up to get clarifications and being referred to specific people following specific regions. I also recall that their reports often differed from the generic reports found at free sources (and AccuWeather generally had a much better track record).
posted by RavinDave at 1:49 PM on August 19, 2007

It depends, I think. I work with aviation weather and the company we contract with supplies some of their own data and some NOAA-generated data. Things like NEXRAD and winds and icing forecasts, they take raw data from NOAA and run their own algorithms on it. NOAA or flight service-issued reports like METARs and AIRMETs/SIGMETs are not altered except to package the data in the way we want it.

NEXRAD is an interesting one to look at because there are many different ways of looking at the data. The weather radars make passes at several different inclinations and ranges, and each company makes decisions on which of those to display. There's actually a big debate in the aviation weather world right now about whether composite radar (that is, adding all the different inclinations in to one image) is more useful than looking at specific angles.
posted by backseatpilot at 2:01 PM on August 19, 2007

AccuWeather is located in State College, PA (which is why Penn State is one of the top Meteorological schools in the country.) I'm sure they use govt data, as well as their own. I think they work on the prediction based on data, but also take into consideration the national weather service.
posted by filmgeek at 2:03 PM on August 19, 2007

A major selling point of AccuWeather is not so much the generic information carried over the wire service -- but some very specific explanations of that those data mean. It's one thing to say you'll receive X temperature at Y time with Z winds -- it's another matter to say you'll get a marked increased risk of hydroplaning at 0930 as underlying ice starts to melt and NE winds kick up to 55 mph.
posted by RavinDave at 2:18 PM on August 19, 2007

My understanding is that the majority of AccuWeather's data comes from the NOAA/NWS. They might have some of their own ground-based stations or other data sources that get integrated with NOAA data (maybe from TV stations* or other independent forcasters who are also clients for their national data?), but whatever they're doing, I don't think it's that significant. Their forecasts never seem to differ much from the official NWS ones. The only difference is that where the NWS is pretty conservative, AccuWeather plays a little more fast-and-loose (the NWS errs on the side of predicting worse weather, and doesn't do some of the long-range forecasting that AccuWeather engages in, and which some meteorologists have called "throwing darts").

In large part, I think AccuWeather basically distributes the NWS's data (which includes predictions for temperature and precipitation). But that could be my cynicism getting in the way, since they've essentially tried to suppress public distribution of NOAA data, or stamp their own copyright on NWS forecasts, in the past.

* There are many TV stations that operate their own weather radar systems (e.g. WFSB's "Doppler 3000" in Connecticut) which AccuWeather might use for additional data, although I'm not sure that the independent radar sites are in any way superior to the NWS's NEXRAD system, which has nationwide coverage already. Perhaps they have some additional local resolution.
posted by Kadin2048 at 3:03 PM on August 19, 2007

Your question is interesting because the current system was nearly changed recently. Former Pennsylvania Senator Rick Santorum introduced a bill called "The National Weather Services Duties Act of 2005" that would "bar the National Weather Service from providing any service that competes with the private sector." In other words, the US taxpayers who pay for NOAA and the National Weather Service to collect the weather data from thousands of stations around the country would not be permitted to get their weather forecasts from the NWS. The NWS would instead have to provide their data for free to private forecasters from which we would have to purchase forecasts. It just so happens that the founders of AccuWeather, Joel and Barry Myers, who have their headquarters in State College, PA, were big contributors to Santorum's re-election campaign in Pennsylvania. Fortunately, sanity prevailed and the privatization of weather forecasting was defeated along with Rick Santorum.
posted by JackFlash at 3:32 PM on August 19, 2007 [2 favorites]

Response by poster: Actually yes there is sort of a political motivation to this. A libertarian might support a bill like the one JackFlash described that would bar the NWS from producing forecasts (which the private sector can do). My point is, the NWS does a lot, lot more than just spit out forecasts, and has a tremendous capital investment in meteorlogical data gathering to accomplish this. I'm interested to know if places like Accuweather basically piggy-back off NWS data collection to produce their own models and forecasts; maybe Accuweather could do just fine without NWS data. I don't know, I'm asking.
posted by Brian James at 5:25 PM on August 19, 2007

Weather forecast computer models are built by collecting weather data on a grid. The finer the grid of data samples the better the model. A part of this consists of readings taken at hundreds of airports by federal employees. The NWS also runs the Cooperative Observer Program which consists of over 11,000 people, most of whom are volunteers, although a few are paid. I doubt that you could get 11,000 volunteers to work for free for AccuWeather. They do it out of a sense of duty and altruism that most libertarians would find irrational. In addition there are hundreds of buoys that NOAA maintains in the distant oceans where much of the continental weather originates. NOAA also operates the weather satellites.

A service like AccuWeather does not have the financial means to collect these thousands of points of data independently. They simply download the raw data from the NWS and process it to produce their forecasts using their own models. The value they add is the ability to produce customized forecasts for commercial purposes. For example a car dealer may want to know which weekend in the summer is likely to have the best chance of good weather for a special sale. Or a highway construction company needs to know when temperatures and precipitation will be best for paving. Ski areas need to forecast the amount of snow on their particular mountain.
posted by JackFlash at 6:49 PM on August 19, 2007 [1 favorite]