TIME weather

Why Experts Get Storm Predictions Wrong—and Why You Should Still Prepare Anyway

It's not easy to predict a snowstorm

Weather forecasters and public officials warned millions to take cover as a blizzard approached the East Coast with the promise of several feet of snow in some areas over the course of the weekend. The power may go out, flights will be canceled and snowfall records could be broken, reports say.

All the hype has left some locals predicting that the storm may be a repeat of last year’s “snowpocalypse” that in urban centers ended up being more of a normal snow day—if that—than an Armageddon level event. Despite the snowpocalypse-induced skepticism, meteorologists and natural disaster experts still urge residents in the path of a storm to heed warnings to prepare. But they also acknowledge that hype can quickly outpace reality.

“One of the things that the meteorological community doesn’t do very well is convey when there is uncertainty,” said Sean Sublette, a meteorologist at Climate Central. Sometimes the hype itself will snowball, he says, and when it gets rolling “it will be difficult to stop.”

No model predicts a storms with 100% accuracy and predicting the strength of a large system at a given place and time can be difficult. As a result, meteorologists can say some things about this weekend’s upcoming storm with near certainty, while other factors still remain up in the air. For example, the blizzard is highly likely to hit Washington D.C. hard with a strong likelihood of extensive damage. But other questions, like how much snow the storm will bring to New York City, are more difficult to answer this early.

Last January’s “snowpocalypse” is just one example of how even a minor misstep can seem like a major meteorological miss. The storm largely spared New York City of the predicted devastation, but New Yorkers might be surprised to know that it did leave two feet of snow just 30 miles to the east on Long Island. That separation makes a tremendous difference for millions of Manhattan residents and the officials charged with protecting them, but represents a tiny deviation for climate experts tasked with making forecasts. “It’s such a small distance, considering we’re sampling the entire atmosphere,” said Sublette. “That’s the challenge the weather enterprise faces.”

Read More: Why We’ll Keep Having Weird Weather in 2016

Snow bands—a small concentrated area typically no more than 30 miles across—can make it even more difficult to predict how much snow or rain will fall in a particular area. These areas can dump several inches of snow in a short amount of time before moving elsewhere.

But just because weather predictions can sometimes be off doesn’t mean they’re not worth taking seriously. Forecasts get more accurate with time and warnings 24 hours before a storm should be considered more seriously than several days before projected landfall.

Those who are skeptical of media reports hyperventilating over the latest “snowmageddon” can even bypass the hype and do the research for themselves. Less flashy forecasts straight from the National Weather Service provide solid information without the tabloid flourish.

Read More: Here’s Where to Buy a House In the U.S. That Will Be Resilient to Climate Change

If disaster response experts have one message to those in storm-targeted areas, it’s to prepare anyway. “You can’t be certain, but the cost of preparing is pretty minimal,” said Russ Paulsen, American Red Cross executive director of community preparedness and resilience services. “There’s a lot better chance that this storm is going to significantly inconvenience your life than the odds were for people who played the Powerball.”

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