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Posted at 01:59 PM ET, 09/22/2011

Farmers’ Almanac: Prepare for “wet, wild winter”


Farmers’ Almanac 2012 winter outlook ( FarmersAlmanac.com )
Get ready for a winter of “clime and punishment” says the Farmers’ Almanac. From frigid conditions in the northern tier of the U.S. to very wet and stormy conditions in the East, it predicts the upcoming winter will be an “unusually” tough one. But should we put much stock in this outlook? I’d say just a very little, and will explain.

First, let’s review the outlook summary:

The upcoming winter looks to be cold to very cold for the Northern Plains, parts of the Northern Rockies, and the western Great Lakes. In contrast, above-normal temperatures are expected across most of the southern and eastern U.S. Near-normal temperatures are expected in the Midwest and Far West, and in southern Florida.

A very active storm track will bring much heavier-than-normal precipitation from the Southern Plains through Tennessee into Ohio, the Great Lakes, and the Northeast. Because of above normal temperatures, much of the precipitation will likely be rain or mixed precipitation, although, during February, some potent East Coast storms could leave heavy snow, albeit of a wet and slushy consistency.

An active Pacific Storm track will guide storm systems into the Pacific Northwest, giving it a wetter-than-normal winter.

Drier-than-normal weather will occur in the Southwest and Southeast corners of the nation.


Typical La Nina weather conditions (NOAA.)
To make a long story short, the Farmers’ Almanac is pretty much describing the typical La Nina winter. The cold northern tier and the active northern storm track (or jet stream) it describes are all things we often see during La Nina. So from a big picture perspective, the Almanac’s ideas are going to be similar to a lot outlooks issued by different outlets given La Nina’s return. Its ideas are not novel.

These big picture predictions based on atmospheric patterns like La Nina are valid, though not without considerable uncertainty.

On the other hand, efforts to provide highly specific and highly regionalized information lack credibility or scientific basis.

There is simply no predictive skill in place-based week to week forecasts weeks to months in the future. I demonstrated last December that the Old Farmer’s Almanac (a different almanac than the Farmers’ Almanac discussed above) offered specific predictions for the mid-Atlantic and Northeast that were close to opposite what actually occurred.

That’s not to say the Old Farmer’s Almanac (or the Farmers’ Almanac) doesn’t sometimes make some good predictions. For example, last winter it called for colder than average conditions in the mid-Atlantic and Northeast during December and January and warm conditions during February. That was spot-on.

Another impressive recent prediction was its forecast for this September in the mid-Atlantic and Northeast. It called for much below average temperatures and much above average precipitation. Pretty good.

But as far as I know, neither the Old Farmer’s Almanac nor the Farmers’ Alamanc have ever published a peer-reviewed study demonstrating the accuracy (or inaccuracy) of their forecasts. The Old Farmer’s Almanac stated its forecast methodology is “closely guarded”. So there’s no way to objectively assess the accuracy of its forecasts or evaluate the legitimacy of its science. Even when it gets a forecast right, is it getting it right for the right reasons?

The bottom line is that these kinds of almanac predictions are fun to review, sometimes on-target, but, until they prove otherwise, of dubious scientific or decision-making value.

Related: It’s Old Farmer’s Almanac Time and Farmer’s Almanac forecast vs. reality in December

By  |  01:59 PM ET, 09/22/2011

Categories:  Latest, Winter Storms

 
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