Summer ended at 10:09 PM, Wednesday, September 22, 2010. Here are my weather observations for the season.
Extreme differences in rainfall amounts highlight my report. Duluth recorded 3.71 inches above normal for the season. Grand Marais showed 1.95 inches below normal. My reports show 3.11 inches above normal.
Grand Portage at the Canadian Border about 40 miles northeast of Grand Marais continues to experience serious drought. My sister’s home at Lake Nebagemon, Wisconsin, about 40 miles inland from the south shore of Lake Superior, recorded nearly 17 inches of rain in June, while I recorded 5.68 inches. I don’t have the official numbers for Wisconsin locations.
The storm track persisted all summer across northern Wisconsin. Lakes flooded. Crops were flattened by inches of hail. Numerous reports came every week, of violent straight-line winds and small tornadoes. My cousins farm 10 miles north of Amery, Wisconsin looked neglected when we visited on September 18, but that condition resulted of two mini-tornadoes and six inches of hail on the ground the week before. Every commercial business in Rice Lake, Wisconsin, where we spent the weekend, had new roofing in progress.
Some of these storms made national headlines. Owatonna, a city on I-35 south of Minneapolis, was one of many that suffered a disaster after flooding rains on September 23. More than 10 inches fell in one day.
Compare the data I collected on my own weather station with the summaries prepared weekly and monthly by the Minnesota State Climatology Office. I send my daily observations online to that office. The Grand Marais summary is most similar to my observations, but variations in the surface temperature of Lake Superior make a big difference.
Northeast MN regional summaries
Mean Temp Departure Precip Departure
April
Little Marais 44.2 5.2 .89 -1.20
Duluth 46.0 7.0 .75 -1.34
Grand Marais 43.0 4.6 .60 -.70
NorthEast 44.9 5.9 .86 -.78
May
Little Marais 50.8 . 2 1.89 -.80
Duluth 53.8 2.0 5.80 2.85
Grand Marais 48.0 .9 1.97 -.53
NorthEast 51.5 .9 3.29 .60
June
Little Marais 57.4 -.8 5.68 1.68
Duluth 60.0 .1 5.07 .82
Grand Marais 55.0 1.7 4.00 .59
NorthEast 58.0 -.1 4.29 .29
July
Little Marais 67.5 3.5 4.00 -.10
Duluth 69.1 3.6 3.45 -.75
Grand Marais 66.0 5.4 3.33 -.05
NorthEast 67.1 3.1 3.75 -.35
August
Little Marais 64.3 1.0 5.05 1.42
Duluth 68.2 4.5 6.99 2.77
Grand Marais 62.2 -.4 1.74 -1.39
NorthEast 65.8 2.5 5.08 1.46
September thru end of summer
Little Marais 46.3 -8.1 2.11 -1.45
NorthEast 59.7 5.3 .84 -2.72
Maintaining a table format I couldn’t figure out. Every time I click save, the columns misalign.
Here’s a link to the Minnesota Climate summaries.
http://climate.umn.edu/cawap/monsum/monsum.asp
Another link to Lake Superior Surface temperatures. Remember the headlines earlier this summer that the lake temperature was much warmer than normal? That was May. The temperature was about 50 degrees, a month early. The lake temperature took a nose dive when early gales began in mid-August. Now the lake temperature is where it should be at the end of September, upper 40′s to mid-50′s, with variations day to day and around the lake
http://coastwatch.glerl.noaa.gov/cgi-bin/stat/statistic?region=s&template=stat
