November and Fall Season Climate Summary
November ended on Tuesday of this week. The month generally brought warmer than normal temperatures, as well as a mixture of above and below normal precipitation.
Temperature-wise, the mean monthly temperature for November ranged from 2 to 5 degrees above normal across the state. On a statewide basis it ranked as the 19th warmest November in history (back to 1895). The highest temperature reading in the state was 74°F at Granite Falls (Yellow Medicine County) on the 6th, and the lowest reading was -13°F at Camp Norris (Lake of the Woods County) on the 25th. Within the state’s climate network there were 9 daily maximum temperature records tied or broken during November, including 62°F at Lamberton and Windom on the 24th.
Precipitation was mixed for the month, with northern areas of the state reporting mostly above normal values, and the rest of the state reporting mostly below normal values. Within the state network of climate stations, the extremes of total November precipitation ranged from just 0.12 inches at Milan to a little over 4 inches in Grand Marais. The heaviest precipitation occurred over November 11-12, with over 40 climate stations reporting new record daily amounts ranging from 1 to 2 inches. Portions of Saint Louis, Roseau, Koochiching, and Beltrami Counties reported over a foot of snow for the month.
Drought conditions improved only slightly during the month as nearly 27 percent of the state landscape (all in the north) remains in Severe to Extreme Drought at month’s end.
Taking a look at the autumn season (September-November) it was much warmer than normal across the state. In fact on a statewide basis, it was the 4th warmest autumn in history (back to 1895), with over 60 percent of the days delivering above normal temperatures.
Here is a listing of the temperature ranking for the autumn season for selected locations around the state:
3rd warmest for the Twin Cities
4th warmest for Big Falls
5th warmest for International Falls, Brainerd, and Morris
6th warmest for Duluth and Rochester
7th warmest for Saint Cloud
8th warmest for Pipestone
The autumn season ranked as the 26th wettest historically on a statewide basis. Some of the areas reporting the most surplus precipitation were in western Minnesota where 10 to 12 inch totals were reported.
For the first 11 months of 2021, the statewide mean temperature ranks 3rd warmest (tied with 2016 and 1998). Only 1987 and 2012 were warmer. For precipitation, the statewide average precipitation for the first 11 months of 2021 is less than 23 inches, the driest such period since 2006.
Weekly Weather Potpourri:
Speaking of warm autumn seasons, the BBC Weather Center reported this week that Northern Ireland recorded its warmest autumn in history. This followed its 3rd warmest summer in history, when a number of temperature records were set.
A study from MIT recently published in Nature Communications shows that there has been an increase in the frequency of Tropical Cyclones in the North Atlantic Basin over the past 150 years. The study was produced under the leadership of Dr. Kerry Emanuel, a leading hurricane researcher well-known for his books and previous studies. In the study it is shown “that most of the variability of North Atlantic tropical cyclone activity over the last century was directly related to regional rather than global climate change.”
The Joint Typhoon Warning Center expects Tropical Cyclone Jawad to bring especially heavy rains to portions of Eastern India this weekend. The storm is expected to travel a parallel path along the coastline, bringing up to 8 inches of rain and wind gusts up to 70 mph to some highly populated areas.
MPR listener question:
You mentioned previously that recent Decembers have shown a remarkable warming trend. How many of the last ten years have brought warmer than normal Decembers to Minnesota? And do you think this December will be warm too?
Answer:
A very strong warming trend in December is evident as 9 of the last 10 Decembers have been warmer than normal in Minnesota (though 2017 was marginally so). But 2015 was the warmest December in state history, nearly 12 degrees F above normal. The only December of the most recent 10 that was cooler than normal was 2013. I do think there is a good chance that this December will be warmer than normal as well. The latest outlook from NOAA suggests that at least the southern portions of Minnesota will see a warmer than normal December.
Twin Cities Almanac for December 3rd:
The average MSP high temperature for this date is 33 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 20 degrees F (plus or minus 11 degrees F standard deviation).
MSP Local Records for December 3rd:
MSP records for this date: highest daily maximum temperature of 62 degrees F in 1962; lowest daily maximum temperature of -1 degrees F in 1886; lowest daily minimum temperature of -19 degrees F in 1940; highest daily minimum temperature of 43 degrees F in 1962; record precipitation of 1.05 inches in 1953. Record snowfall is 7.4 inches in 1934.
Average dew point for December 3rd is 19°F; the maximum dew point on this date is 54°F in 2012; and the minimum dew point on this date is -22 degrees F in 1940.
All-time state records for December 3rd:
The state record high temperature for this date is 72 degrees F at Canby (Yellow Medicine County) in 1941. The state record low temperature for this date is -38 degrees F at Itasca State Park (Clearwater County) in 1927. The state record precipitation for this date is 2.42 inches at Big Falls (Koochiching County) in 2013. Record snowfall is 17.7 inches at Two Harbors 7NW (Lake County) in 2013
Words of the Week: Afterheat and Aftersummer
These are very old terms used to refer to the warm pleasant days in the late autumn (at or after Indian Summer). It was thought that the residual heat of summer stored in the ground was released under sunny skies and helped produce temperatures that were well above normal for the late autumn. Though the soil does indeed accumulate and store heat during the summer months, periods of late autumn warmth are more often attributed to advection - the regional-scale transport of heat carried in the surface winds from one area to another. Temperatures which reach 10 to 20 degrees above normal this time of year cannot be generated locally by the low sun beating down on the Earth or by heat released from the ground.
Past Weather Features:
The coldest December 3rd on a statewide basis was in 1927 when all places in the state except a few southern counties reported subzero temperatures. Many areas in the north were recording minimum temperatures in the minus twenties and minus thirties. The afternoon high only reached -2°F at Campbell (Wilkin County)
Perhaps the warmest December 3rd in state history was in 1998 when over 50 Minnesota communities reported afternoon highs in the 60s. Many golf courses were open and busy. Many areas enjoyed three consecutive days in the 60s F (December 2-4), and several took their lunch citizens took their lunch breaks outside.
Northeastern Minnesota was caught in a strong winter storm on December 3, 2013 when 8 to 16 inches of snow fell, closing some sections of Hwy 61 along the north shore of Lake Superior. It proved to be the start of a snowy month for many north shore communities where 30 to 40 inches of snow fell before the end of December.
Outlook:
Cooler over the weekend with temperatures closer to normal, and a chance for snow late Saturday and into early Monday. This winter storm could deliver 6 inches to a foot of snow in portions northeastern Minnesota. The weather will be a bit colder and drier for the balance of next week.
Comments