Paul Douglas, founder of Weather Nation, a weather outsourcing company in the Twin Cities, takes a dim view of the reliability of long-range forecasts.
“It’s like asking your banker what your interest rates are going to be in the middle of 2013,” he said. “Good luck with that. There are billions of variables.
“The future is wonderfully unknowable. Anybody who pretends to have an answer key for the winter to come is trying to sell you something, and I can’t stress enough, ‘Buyer beware.’”
Many weather predictors consider the temperature of surface waters in the tropical Pacific Ocean. Warmer waters than normal are called El Nino, and cooler waters are called La Nina. Together, the cycle is called the El Nino-Southern Oscillation (ENSO); together, they can have huge impacts on temperature and precipitation readings across the country.
It looked like an El Nino was setting up earlier this fall, Douglas said, but the chances of that happening have since dropped to 53%. When it does occur, an El Nino tends to push the jet stream southward, increasing the likelihood of wet weather in the south-central and southeastern US with mild, dry conditions in the northern states.
But the trends don’t always occur as predicted, as in last year’s La Nina. Many forecasters had predicted a cold and snowy winter up north, but much of the US saw record-breaking warm temperatures.
In making his predictions, meteorologist Larry Cosgrove, of the forecasting company WEATHERAmerica in Hockly, TX, considers ENSO along with other weather-influencing conditions, such as sunspot number, wind speeds in the upper atmosphere, and the severity of current droughts.
He then scouts through decades of data to find analogous years for each condition and throws all the data into what he calls his own “whirring blender technology” to determine his upcoming predictions, which he says are accurate 60-70% of the time.
And here’s his prediction for this year: A tough winter in New England and the Northeast, cold and wet weather through January and February.
The middle of the country from Colorado to Ohio and south to Oklahoma and Arkansas can expect plenty of snow and ice.
Minnesota and Wisconsin will be cold but not extremely snowy as the storm–track bears further south.
And he says the west will probably be mild.
He expects “a quick exit to spring, and a very warm spring at that” beginning in March.
“If I had to zero in on one period (that) snow and ice-lovers would really like, it would be the week of Christmas and New Year’s through January up to Valentine’s Day. That’s the strike zone.”
The Farmer’s Almanac predicts mild and dry for the upper Midwest, cold and dry for New England, and snowy and cold for the Mid-Atlantic and Ohio Valley into the Carolinas.
Douglas says the Almanac is right about half the time.
Source: Discovery News, November 9, 2012