Tuesday, October 16, 2012

How much value does Winter forecasting provide?

During the 2011-12 snow season, the Twin Cities picked up 22.3 inches of snow, which was the ninth least snowiest season ever.


Many prognosticators were expecting much more snow during this La Niña period.  AccuWeather, a national private weather service, made perhaps the boldest and strongest statement when it issued it’s 2011-12 winter forecast in October 2011.


The Midwest was expected to be hit hard by Old Man Winter that season, according to this weather service.  AccuWeather’s long-range meteorologist, Josh Nagelberg, declared, "People in Chicago are going to want to move after this winter."


When it was all said and done, AccuWeather missed the forecast by nearly three feet of snow, and not too many Midwesterners were overly anxious to leave town.

AccuWeather Forecast Actual Error
MSP 56” 22.3” 33.7”

The long-time trusted publication since 1818, Farmers’ Almanac, released it’s seasonal winter forecast, indicating a very cold, but average snowfall.


It was anything but cold for the Twin Cities. We experienced the fourth warmest winter on record. The 30-year average (or normal) for snowfall in the Twin Cities is 54 inches.


Farmers’ Almanac did not fare much better when it came to last season’s snowfall prediction with a similar forecast as AccuWeather.

Farmers’ Almanac Forecast Actual Error
MSP 54” 22.3” 31.7”

Locally, KSTP-TV meteorologist, Dave Dahl, proclaimed the Twin Cities would see a whopping 75 inches of snow for the season!

Screen shot 2011-10-28 at 9_31_51 PM

Unfortunately, Dahl was off by more than four feet of snow.

KSTP-TV Forecast Actual Error
MSP 75” 22.3” 52.7”

Local weather bloggers Paul Douglas and Paul Huttner had very similar predictions with near average snows. Douglas called for 50 to 55 inches of snow, while Huttner guessed 55.

Paul Douglas Forecast Actual Error
MSP 50-55” 22.3” 27.7-32.7”
Paul Huttner Forecast Actual Error
MSP 55” 22.3” 32.7”

A local statistician, Rigil Kent, for the The Minnesota Forecaster attempted a more data-driven, historical approach to snow forecasting.  He determined that 62.1 inches of snow would fall.  The winter didn’t play by the rule of probabilities.

Rigil Kent Forecast Actual Error
MSP 62.1” 22.3” 39.8”

The most accurate snow prediction I could find last season is attributed to the owner, and weather enthusiast of The Minnesota Forecaster, Bill Stein.  His prediction involved the amount of shedding by his dog, of all things.  His 43.1 inches call was closest to 22.3 inches of actual snow, but more than 20 inches off the mark.

Bill Stein Forecast Actual Error
MSP 43.1” 22.3” 20.8”

The private sector did not fare all that well with winter outlooks, so how did NOAA do?  Not much better.  Their revised 2011-12 forecast issued in December 2011 called for above normal precipitation for much of the northern tier of the continuous United States.


What does this all mean?  Winter forecasting should be taken with a grain of salt.  It is nothing more than just a guess.  Weather often doesn’t play by a regular set of rules, whether it’s an El Niño, La Niña, or neutral year.  Weather patterns can disrupt these seasonal influences.  In addition, predictions from local members of the media are not any better than national ones.

Willing to take a shot on how much snow will the Twin Cities see in 2012-13?  Post your guess below!


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