Well we had our first snowstorm of the season and it was a big one. No easing into the winter of 2022-2023 for us.
Big storms in November are not as common as you might think. Some of our most notorious storms do happen in November but they’re pretty rare. The last real big one was the Halloween Blizzard of 1991, which many people forget fell mostly into Nov. 1, but began on Oct. 31. The Armistice Day Blizzard of November 11-13, 1940 is another notorious storm that dumped 16.8 inches of snow and killed 154 people, 49 in Minnesota.
One of the trademark tales of November storms are huge temperature swings. In the Armistice Day Blizzard temperatures plummeted from the 40s and 50s into the teens. There were many a tale of duck hunters caught in the elements, dying, some heroically finding their way to safety.
Our recent storm saw highs in the 50s Friday and Saturday and even 43 on Monday before dumping 8.4 inches of snow less than 24 hours later.
While big snows (8 inches or more) are actually not that common in Minnesota, if they’re going to happen, your better chance is in November or March. That’s because the atmosphere is warmer and a warmer atmosphere holds more water vapor available to make for bigger snowfalls. That’s why the nor’easters dump huge amounts of snow. Minnesota is white for a chunk of the winter mainly because it’s cold enough to not melt off our snow rather than us receiving a whole lot in a season.
If we sort November snowfalls in the Twin Cities that are 8 inches or more (within a 24-hour midnight to midnight period), we see there aren’t a whole lot:
There are only about 8 in 142 years of records. Now the key here is that this is measuring midnight to midnight 24-hour totals. Some storms fall over two days, but this is a quick, easy way to sort out the data to get the basic idea that big snows aren't all that common in November.
We just happen to be lucky enough where we did have a big storm just a few years ago in 2019. November 26-27 that year dumped 9.2 inches of snow in the Twin Cities. Before that however 2001 was the only other November snowstorm to be bigger than this year’s since the 1991 blizzard of Oct. 31-Nov. 1.
Often times these big snowstorms push snow totals for the whole month up into top spots. This year is the 2nd snowiest November in 25 years and the 16th snowiest overall (of 142 years) with a total 13.0 inches. The normal November snowfall is just 6.7 inches using the 1991-2020 average, which is even skewed a bit high thanks to the snowiest November ever of 1991 with 46.9 inches!
Monthly snowfall totals of more than 15 inches (38 centimeters) have occurred almost two-and-a-half times more in the Minneapolis-St. Paul area since the Metrodome was built in 1981 compared to the 50 years before its construction, according to the Union of Concerned Scientists.
Even though the biggest snowstorms are not very frequent, we are seeing snowfall overall in the month of November gradually increase as November temperatures warm. Again, this is because a warmer atmosphere holds more water making storms bigger, producing more precipitation.
While Minnesota is warming rapidly, it’s still cold enough – most of the time – in winter to produce snow versus rain. Of course, that snow/rain line is trickier in November and March but if you time the cold out just right, you get big snow.
When we look at the winter overall, we see a dramatic difference. If you add a couple inches to each winter month, of course it’s going to add up. While trend lines are helpful (the zig zag line shows the 5-year running average), sometimes just looking at two different averages can really tell the story. The average seasonal snowfall for the first 80 years of Twin Cities records (1880-1960) was 41 inches. Since 1960, that average is 54 inches, more than a foot more of snow per winter!
Winter enthusiasts know full well this is not translating to deeper snow pack everywhere. That’s because, with warming winter temperatures, that snowpack is less dependable and often melting or seeing rainfall events in between, much more than historically. For the time being, northern Minnesota remains cold enough to hold onto some of that extra snow and snow cover is actually increasing.
If you’re a snow lover, let’s hope this isn’t it for big storms this season. Too often in recent years, it has been. Last winter (2021-2022) we had our biggest storm early in the season on Dec. 11 with 11 inches (that all melted and we had tornadoes a few days later!) and in 2020 we had an 8.7-inch snow on Dec. 23. The remainder of both winters were pretty lackluster, so a big storm early doesn’t mean anything about what’s ahead.
There are some hopeful signs for December with a potential blocking pattern developing, which you’ll hear more about from me in the coming days.