Textbook La Niña winter unfolding in Minnesota

This winter is following the La Niña playbook in Minnesota.

Last September I wrote about a developing La Niña event in the tropical Pacific Ocean. La Niña events show about a 70 to 80 percent correlation historically with colder and snowier than average winters in Minnesota and the Upper Midwest. They also have a bias toward milder-than-average fall weather.

So far last fall and this winter are playing out nearly perfectly by the La Niña playbook.

Temperatures

Milder-than-average temperatures prevailed in the fall for Minnesota. Here are the temperatures compared to the average for (meteorological) fall of 2021 in the Twin Cities.

• September, 3.0 degrees above average

• October, 6.1 degrees above average

• November, 2.2 degrees above average

I’ve observed that in many years La Niña-like conditions seem to kick in in the last two-thirds of winter. So far this winter’s temperature trend is following the classic La Niña pattern.

Here are temperatures compared to average so far this meteorological winter in the Twin Cities:

• December, 2.5 degrees above average

• January, 5.5 degrees below average, so far

Looking at forecast temperatures for the last week of January, it looks like our January will end up around 5 to 6 degrees below average overall. That will put our winter average temperature for the first two-thirds of meteorological winter at about 1.5 degrees below average as we move into February.

The National Oceanic and Atmospheric Administration CFS2 latest climate forecast for the month of February shows a slight bias toward colder-than-average temperatures overall for February in Minnesota.

Snowfall

So far, snowfall is running slightly above average for most, but not all, of Minnesota this winter.

Here are some select snowfall totals vs. average for Minnesota so far this winter.

• Twin Cities, 32.9 inches (5.2 inches above average)

• Fargo-Moorhead, 39 inches (11 inches above average)

• Wolf Ridge ELC (Finland), 60.7 inches (7.6 inches above average)

• Duluth, 48 inches (nine-tenths of an inch below average)

• Rochester, 21.8 inches (one-half inch below aveage)

February outlook

Right now, NOAA’s 30-day outlooks for February suggest equal chances for above- or below-average temperatures across Minnesota and the Upper Midwest:

The February precipitation outlook also favors equal chances for snow above or below average.

Overall, it appears this winter will most likely come in near or slightly colder than average across much of Minnesota, with near to above-average snowfall.

In other words, a classic La Niña winter pattern.

Stay tuned to see how February unfolds.