Understanding the process: Why forecasting a ‘chance of snow’ more than a week out is tricky

Local News

MOUNT PLEASANT, S.C. (WCBD) – Whether you love it or hate it, snow is always a word that gets everyone talking in the Lowcountry. A quick check of your phone’s weather app on Friday may be showing a snowflake icon for next Sunday.

But don’t get your hopes up just yet. Storm Team 2 Meteorologist Josh Marthers explains what needs to happen before we see a few flakes, and why forecasting a chance of snow is too tricky more than a week out.

Phone apps showing a snow icon for next weekend – that’s eight to ten days from now – should be taken with a grain of salt. However, Josh Mathers says the pattern is right for moisture and cold air to “play games across the southeastern United States” next week.

“Does that mean a cold rain, or something else? Only time will tell, as guidance is so sloppy that far in the future,” said Mathers. “Remember, most weather apps use only raw model data to generate their forecasts, and that can lead to BIG errors, especially in the longer range.”

He says meteorologists won’t be able to determine a threat of winter weather, if any even exists, until later this weekend or early next week.

“So, at this point, I’d bank on a cold rain, and not much else,” Mathers said. “There’s a reason we don’t see snow and ice in the Lowcountry often, it’s really hard to get every single ingredient necessary this far south and so close to the Atlantic Ocean.”

We all know weather in the Lowcountry – it can change on a dime. Your best bet? Stick with Storm Team 2 for the latest update and they’ll iron out the details in the days to come.

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