After a winter that will be remembered for freakish heatwaves, record snowdrifts, and deadly flooding, the weather is feeling less predictable than ever. Which is why, when AccuWeather announced a brand new 90-day forecast tool last week, it sounded a little good to be true.

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Is it? Yes. It’s misleading as hell, and meteorologists are not having it.

“AccuWeather is putting out a product that has no demonstrated value, and they’ve never proven otherwise,” Jason Samenow, a meteorologist with the Washington Post Capital Weather Gang, told Gizmodo.

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Weather forecasts are notorious for being wrong, and their accuracy diminishes sharply with time. Most meteorologists agree that daily forecasts beyond 7 to 10 days are borderline useless.

But not AccuWeather. The private forecasting company has spent years pushing the envelope (a euphemism for “sparking the ire of the meteorological community”) by issuing longer-term forecasts than anyone else is in the game. In 2013, AccuWeather began releasing 45-day forecasts, prompting Samenow to conduct an independent analysis of the tool. His conclusion? It’s a joke, offering no more accurate information than historical average conditions.

It’s no surprise that AccuWeather’s 90-day forecast tool is already raising eyebrows. I didn’t want to write it off immediately, so I reached out to AccuWeather to learn how accurate (get it?) the company itself believes a 90-day forecast really can be. I asked AccuWeather if it can estimate a probability that its 90-day forecast will be correct, and how the reliability of the 90-day forecast compares with that of shorter term forecasts.

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“There’s a lot of ways to look at that,” Jon Porter, vice president of Innovation and Development at AccuWeather told me, before launching into a canned response on topics ranging from information availability to proprietary weather prediction technology.

AccuWeather offered no estimate of the accuracy or reliability of its 90-day prediction tool, although Porter did stress that users have found the tool to be “valuable and interesting.” Like the 45-day prediction tool, the 90-day forecast appears to collate information from a range of weather models, as well as an extensive historical archive.

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I asked whether I could use AccuWeather’s 90-day prediction tool to plan a wedding in July. Porter emphasized that the 90-day prediction tool is more about long-term trends.

“With regard to planning a specific event, we’re always telling people not to focus on a specific day, but to look at the time period around it to get the trends,” he said. “Is it going to be a dry, cool time, or a warmer, wetter time?”

Sounds reasonable enough. At this point, I had not actually seen the 90-day forecast tool. So when Porter and I got off the phone, I went over to AccuWeather’s website to take a peek at the long-term outlook for Philadelphia. Based on our conversation, I expected to find a tool that presented weekly or monthly temperature and precipitation estimates out to 90 days, maybe even some margins of error. Instead, this is what I found:

Image: AccuWeather screenshot

There’s no nice way to say it: this forecast is nonsense. And I’m pretty sure AccuWeather knows it—the company itself told me that the 90-day forecast tool is “more about long-term trends than individual days.” How on Earth the average layperson is supposed to glean that from a tool that literally presents individual, day-by-day forecasts out to 90 days, with no obvious disclaimers, is beyond me.

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“These forecasts have no value at all,” Cliff Mass, a meteorologist and professor of atmospheric science at the University of Washington told Gizmodo. “I could give you an hour-by-hour forecast 70 years from now, but it wouldn’t mean anything.”

A long-term forecast for Ocean City, NJ Image: AccuWeather

Still, many people may be misled. For instance, confronted with today’s 90-day forecast for Ocean City, NJ, a New Yorker may well decide to book her favorite beachfront property for the 7th through the 9th, rather than risking that thunderstorm (60 percent chance!) on Sunday, July 10th.

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I’m not blaming AccuWeather for wanting to provide folks with long-term data, and it’s possible that these 90-day forecasts are somewhat better than what I’d come up with drawing random forecasts out of a hat. (How much better? I really can’t say.) But the company needs to be real with folks about what it’s offering, and display the information in a manner that emphasizes the uncertainty. During our conversation, Porter stressed that AccuWeather believes the public has a right to as much forecast information as possible.

“Meteorologists have this type of information available,” he said. “It’s a question of making the information available to the public and taking a leadership role.”

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To meteorologists, however, the idea that you can’t trust a 90-day forecast is second nature. As Samenow puts it, “I’m not going to look at models that provide data out to 90 days because I don’t think they’re any good.”

But to the average human who wants a tool that can answer questions like “What will it be like when I go on vacation?” AccuWeather’s new forecasts will surely disappoint.