Forecast: A 71% chance of a mild winter

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NOAA CPC winter outlook favors a mild winter for the Upper Midwest.

The bets are in on the coming winter. It basically boils down to weather lore versus climate prediction science.

If you believe NOAA we should end up milder than average when the winter numbers roll in. If you believe the "Almanacs" or the woolly bear, you may dig deeper into the woodpile this winter.

Predictions from the CPC are that this will likely be a moderate strength El Nino event. (Pacific SST's +1.2 to +1.8 degrees) The Twin Cities NWS has a nice little recap of what moderate El Nino winters have brought to the Twin Cities since 1950. Five of seven moderate El Nino winter have featured mild temperatures. That's 71.4% of the time. The sum total is winter temps 3.1 degrees warmer than average in moderate El Nino years.

We may know if this winter is going to pan out mild early on. It is interesting to note that every December has been milder than average in the Twin Cities, St. Cloud and Eau Claire during moderate El Nino years.

Winter snowfall was below seasonal average most of the time. The average snowfall for the Twin Cities during meteorological winter (December-February) is 45.6 inches. The average for moderate El Nino years is 38 inches.

Here are some more noteworthy items from the NWS report:

-The large snowfall in 1991-92 at MSP was due in large part to the Halloween blizzard, followed by another large snow storm near Thanksgiving, for December through March, snowfall was below normal.

-At all 3 locations, the average temperature for the month of December was above normal for every winter listed. Even the bitterly cold winter of 1965-66 (when the average temperature at STC for January was -1.4o C!) had an above normal December temperature.

-Temperatures in January and February showed much more variability, with some of the winters having below normal temperatures for one or both of the months.

-For years where snowfall was above normal, this was largely aided by a couple of significant early season (Oct/Nov) snowfalls.

Both the Farmer's and Old Farmers Almanacs are calling for a colder than average winter in the Upper Midwest. I don't put much faith in these. But I did see a woolly bear caterpillar with the narrowest brown band in the middle I have ever seen today. Weather lore says that means a cold winter.

So it's the woolly bear and the Almanacs versus NOAA. Let's see where the weather chips fall this winter.

Right now my money is still on NOAA.

PH