The Farmers’ Almanac got it right. The Feds didn’t. No one can escape this winter has turned into a doozy for much of the eastern two-thirds of the U.S.
The giant “blocking” pressure system or “ridge” in the West – cutting off the Pacific’s pivotal moisture feed to California and spiriting a rush of warmth into Alaska – has repeatedly directed frigid air from the Arctic on a single lane smack into the central and eastern U.S.
The frequent polar vortex intrusions have meant wave after wave of cold and snow from the Northern Plains to the Mid-Atlantic. Cold weather milestones and snow tallies have amassed in impressive form. Consider these statistics:
- Chicago has had its 5th snowiest winter on record, with 67.9 inches (normal year-to-date 26.7″); it has also had 22 subzero days, 4th most on record
- Philadelphia has had its 3rd snowiest winter on record, with 58.4 inches (normal year-to-date 16.4″)
- New York City (Central Park) has had its 7th snowiest winter on record, with 57.1 inches (normal year-to-date 18.1″)
- Indianapolis has had its snowiest winter on record, with 52 inches (normal year-to-date 21.2″)
- Detroit has had its 3rd snowiest winter on record, with 77.3 inches (normal year-to-date 30.3″); it’s also having its 5th coldest winter on record to date, with an average temperature of 20.3 degrees
Incredibly, the National Weather Service office serving the Upper Peninsula of Michigan (including Marquette) in Negaunee recorded a 75-day streak with temperatures at or below 32 degrees – all the way back to December 5, which finally ended today.
The unrelenting cold helped ice on the Great Lakes expand to 90 percent coverage last week, the highest level since 1994.
Related: Frigid Winter Locks Great Lakes in Ice (Mashable)
The harsh winter flies in the face of the seasonal outlook published by NOAA, which said winter temperatures could go either way, but gave the edge to warmth. Both Business Week and the Atlantic published articles exposing the flawed prediction. Writes Business Week:
[NOAA’s Climate Prediction Center] grades itself on what it calls the Heidke skill score, which ranges from 100 (perfection) to -50 (monkeys throwing darts would have done better). October’s forecast for the three-month period of November through January came in at -22.
Before we’re too hard on NOAA, consider The Atlantic’s apt summary on why seasonal forecasting is so hard:
Meteorology has made tremendous strides with predicting temperature and precipitation within 24- and 48-hour periods. But once you get past eight days, chaos reigns. And when you get out past a week, and you’re predicting climate’s effect on temperature, your estimates become exquisitely sensitive to the smallest consequential changes. In fact, the Butterfly Effect—the idea that a butterfly’s wings in Brazil can trigger a tornado in Texas—comes from a 1972 paper on chaos theory by Edward Lorez, a former meteorologist.
The trouble with predicting the next three months of temperatures is that weather is a dynamic system, where small changes can yield huge variances in outcomes. After a little more than a week, predictive models are swarmed by the butterfly wings of chaos.
NOAA, for its part, stressed the difficulties in developing this year’s winter outlook, during its public release. Consider my discussion of NOAA’s outlook published in November:
Strong climate patterns that offer long range predictability are absent this year, NOAA said.
“It’s a challenge to produce a long-term winter forecast without the climate pattern of an El Niño or a La Niña in place out in the Pacific because those climate patterns often strongly influence winter temperature and precipitation here in the United States,” said Mike Halpert, acting director of NOAA’s Climate Prediction Center.
(Note: Our own Capital Weather Gang winter outlook is not going to turn out well, and we’ll offer comment on that after the winter is over.)
The saying goes if you throw enough darts, you’ll eventually hit a bulls-eye. So the Almanac can celebrate its solid winter temperature prediction for parts of the country, but that success has to be considered in a context of numerous other forecasts which have fallen short.
The bottom line is that – irrespective of the source – seasonal forecasting is a relatively young, immature science and should be viewed with some skepticism.
As cold and snowy as it has been, more is on the way and more records may fall. Computer models since yesterday have forecast another arctic blast for the eastern two-thirds of the U.S. next week.
NOAA’s outlook for the period 6-10 days from now is unmistakably cold.
The reaction of a forecaster from the National Weather Service in Chicago to what he’s seeing on the weather maps?
[COMPUTER MODELS] PAINT SUCH A BLEAK … DISMAL … COLD… AND POTENTIALLY SNOWY PICTURE NEXT WEEK THAT ITS LIKELY TO LEAVE MANY WINTER WEARY SOULS READY TO CURL UP INTO THE FETAL POSITION AND BEG FOR MERCY FROM OLD MAN WINTER!