Summer's Climate Ranking:
Now that we have put the month of August (warm and wet) in the record books, we might assess the overall climate pattern across the state for summer (June-August). On a statewide basis this was one of the top 4 warmest summers in history (since 1895, averaging nearly 3 degrees F above normal for all three months combined. The summer of 1988 remains the warmest in state history, but 2020 will follow close behind with 1933 and 1983. Within the climate station network of Minnesota this summer 135 daily maximum temperature records were set or tied, while 143 warm daily minimum temperature records were set or tied. The highest temperature was 102°F at Granite Falls on June 7th. In addition, Benson, Sabin, Artichoke Lake, Milan, and Morris all reported at least one day with 100°F as well.
With a statewide average rainfall of about 13.75 inches for June-August, the summer of 2020 will rank as the 17th wettest in state history (back to 1895). Many climate stations reported over 20 inches of rainfall for the summer, while some reported their wettest summer in history, including:
Ottertail with 22.03 inches
New York Mills with 18.36 inches
Hallock with 17.21 inches
Within the statewide climate station network 142 new daily record rainfall values were recorded, with many over 3 and 4 inches. There were also a number of large hail reports around the state, especially in southern and western counties.
Overall, the summer growing season was favorable for many crops this year, and not just the large-scale ones like corn, soybean, potatoes, and sugar beets. Producers also reported bumper crops of tomatoes, green beans, squash, and cucumbers. Other garden crops have done well too.
24th Annual State Fair Weather Quiz:
Even though the State Fair has been cancelled this year, Minnesota Public Radio will be hosting the 24th Annual Minnesota State Fair Weather Quiz Program on Labor Day (September 7) from 11am to noon on FM 91.1. Former Midday Host and anchor of political reporting at MPR Gary Eichten will host the show. Though we cannot give away prizes, we will take listener calls, and I will also get to ask listeners questions about weather and climate topics. It should be fun. If you cannot listener on Labor Day, the quiz will be hosted on the MPR web site to test your knowledge. Try it and see how well you can do.
Weekly Weather Potpourri:
This week NOAA features an article about the wildfires in California which have burned over 1 million acres of land. They discuss the role of drought in wildfire risk, as well as how climate change is affecting the overall risk.
Typhoon Haishen in the Wester Pacific Ocean was producing sustained wind speeds over 140 mph this week, with wave heights of 45-50 feet. It is headed towards southern Japan, where it may make landfall later in the weekend, then move on towards South Korea. The BBC reports.
A report from the University of Alaska-Fairbanks featured in Science Daily this week documents the loss of sea ice in the Bering Sea. The loss of ice has been so extreme that it is estimated to be at the smallest extent in the last 5000 years. There has been a consequential shift in atmospheric patterns over that portion of the Arctic.
This week’s AGU-EOS bulletin features an interesting article about the increased frequency of wildfires in eastern Siberia and the impact on the loss of permafrost there. There is a great deal of variability there in the rate and depth of sinking ground as a result of permafrost loss.
MPR listener question:
I know this question may surprise some listeners but when was the last time it snowed during September here in the Twin Cities?
Answer:
I know that some people get excited about the snow season, but it is a little early for that. There were traces of snow recorded during September in 2016, 2010, 20071998, 1995, and 1992. The last September that brought measurable snowfall was in 1985 (0.4 inches on the 24th).
Twin Cities Almanac for September 4th:
The average MSP high temperature for this date is 76 degrees F (plus or minus 9 degrees F standard deviation), while the average low is 58 degrees F (plus or minus 7 degrees F standard deviation).
MSP Local Records for September 4th:
MSP records for this date include: highest daily maximum temperature of 98 degrees F in 1925; lowest daily maximum temperature of 59 degrees F in 1920; lowest daily minimum temperature of 39 degrees F in 1974; highest daily minimum temperature of 73 degrees F in 1960; record precipitation of 2.08 inches in 1911. No snowfall has been reported on this date.
Average dew point for September 4th is 55°F; the maximum dew point on this date is 74°F in 1960; and the minimum dew point on this date is 35°F in 1974.
All-time state records for September 4th:
The state record high temperature for this date is 103 degrees F at Beardsley (Big Stone County) in 1922 and at Pipestone in 1925. The state record low temperature for this date is 22 degrees F at Park Rapids (Hubbard County) in 1885 and at Grand Rapids (Itasca County) in 1918. The state record precipitation for this date is 5.53 inches at Chanhassen (Carver County) in 2005. No snowfall has been reported on this date.
Past Weather Features:
The hottest September 4th in state history occurred in 1925 when 9 Minnesota counties saw afternoon temperatures reach the 100°F mark. Much of the rest of the state reported temperatures in the 90s F.
Widespread frosts were reported on September 4, 1885 bringing an end to the growing season. Many observers in central and northern Minnesota reported morning lows in the 20s F. At Moorhead the daytime high only climbed to 54°F
Strong and slow moving thunderstorms brought very heavy rainfall to portions of central Minnesota over September 3-4, 2005. From 2 to 5 inches of rain fell in the southwest Metro Area of the Twin Cities. Flooding roads and parking lots were common throughout the west Metro Area and also around Sauk Center.
Outlook:
Warming trend over the weekend with a chance for showers Saturday night, mostly in southern counties. Cooling down for Labor Day with increasing cloudiness and a chance for showers both Monday and Tuesday. Generally continuing cooler than normal much of next week as well, with periodic chances for showers.
Comments
Thanks
I just ran the numbers for 2020 meteorological summer and was surprised to find that 2020 at my home was actually a bit warmer than 1988. The June-Aug average in 2020 was 65.1F. In 1988 it was 64.9. For the 1988 - 2019 period, the average Jun-Aug temperature is 62.1F My memory tells me it was much warmer in 1988, but I think that was because there were so many hot days over 90F in July. Since 1988, days over 90F here are quite rare, and this year the high temperature for the summer was 89F. But with the higher dewpoints we seem to have now, nights were significantly warmer in 2020, which made the difference for the two meteorological summers.
I am located approximately 1/4 mile from the southeast shore of Park Lake, and my records begin in August 1987. The most significant overall trend I have been noticing is more moderate temperatures for both summer and winter, which I attribute to higher dewpoints year round. (I do not have a record of dewpoints). Another trend seems to be later onset of winter and more increased snowfall or cold in April, although this might be contaminated by a couple of unusual years for the month of April.
Joel Rosen