Sunday, September 21, 2014
Inquirer Daily News

45-day forecast!?

AccuWeather going way, way, out on forecasting limb.

45-day forecast!?

If you’re planning to take off  the week of Sept. 15 and spend time around here, the weather is looking fabulous every day except Thursday, the 19th, at least according to AccuWeather.

About a third of an inch of rain is in the forecast for that day, with an additional 0.6 at night, with 11 hours of rainfall total. The forecast is for real.

To howls of skepticism, AccuWeather this week began issuing 45-day forecasts. For those of you keeping score, that’s half a season!

One commenter on the AccuWeather site said the news release announcing the new, very extended forecasts read as though it walked out of the Onion, the well-known parody sheet.

Jason Samenow, meteorologist for the Capital Weather Gang, wrote, “In reality, it is simply peddling a useless product to people who don’t know better.”

“There’s little forecast skill beyond 10 days,” says Eric Horst, head of the Weather Information Center at Millersville University.  

Ten days! Some of our readers may be asking, can the weathermen tell what’s going to happen in the next 10 hours, or the next 45 minutes?

“That’s understandable,”  Jonathan Porter, an AccuWeather meteorologist who is  director of innovation and development, said of such skepticism.

Without divulging trade secrets, Porter said the outlooks will be compiled through a combination that includes  computer models; “teleconnections,” for example, the likes of the El Nino Southern Oscillation in the tropical Pacific, which affects weather in the United States, and old-fashioned climatology.

In short, a blend of short-range and seasonal forecasts.

Did we ever tell you how amusing the atmosphere finds long-range outlooks?

Porter said the real value of the outlooks would be to give the public some idea of “trends,” whether a given period would be cooler or wetter than normal.

The implication is that the outlooks shouldn’t be taken quite literally.

That said, the outlook for each day in the period is quite specific, with highs and lows and precipitation amounts.

Porter said the object of the specificity is to make the forecasts “relatable to people.”

He didn’t mention this, but we suspect that if the forecast draws more online traffic, no one at AccuWeather would complain.

Tony Wood Inquirer Weather Columnist
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Tony Wood Inquirer Weather Columnist
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