Roller Coaster Climate PatternThe climate patterns this month have been classic for Minnesota....that is to say highly variable. We started on the 1st with many reports of daytime temperatures in the 70s F. In fact over 20 western Minnesota communities reported daytime highs of 70 F or above. Then on the 4th of the month 35 Minnesota communities reported record-setting cold daytime maximum temperatures with their thermometers remaining in the 30s and 40s F all day. Windom only rose to 43 degrees F, while Cass Lake barely reached 38 degrees F for a daytime high. The next morning (October 5th) Zumbrota (Goodhue County) reported a record-tying minimum temperature of just 23 degrees F (tied 1952). The remainder of the week was cold with frequent frosty mornings. By October 9th about two-thirds of the state's weather observers have reported at least one frost this autumn.
Also over October 4-5 over 30 communities reported a trace of snowfall, while the Brainerd area reported 0.6 inches, one of the earliest measurable snowfalls observed there. More recently this week temperatures have moderated and will rise to near seasonally normal levels by early next week. Further temperatures are supposed to be warmer than normal for much of the mid-month period. It is possible many areas of the state will see 70 degrees F again with an extended Indian Summer.
Changing day length effects on temperatureAs we continue to lose daylight hours this month, you may notice an increase in the daily temperature range. Though the sun will heat the dry landscape substantially during the day (as we have seen this week), the longer nights allow for more cooling to occur, dropping the overnight lows to a greater degree than just a month ago. This produces a larger daily temperature range in the absence of significant cloud cover (note many observers reported a 30-35 degrees F temperature rise on Monday, October 6th).
Another temperature effect of day length is change in the time of day that the maximum temperature occurs. Again, in the absence of persistent cloud cover, or drastic change in air mass because of a strong frontal passage, the time of the maximum temperature is typically 5:00 to 6:00 pm in July, 4:00 to 5:00 pm this time of year (October), and during the very short days of December, the maximum temperature occurs between 3:00 and 4:00 pm.
Weekly Weather potpourri:Super Typhoon VongFong was generating wind gusts over 150 mph this week and sea wave heights of 40-45 feet. It was on a track to bring heavy rains, high seas, and damaging winds to parts of South Korea and Japan over the weekend.
Also, Cyclone Hudhud in the Bay of Bengal was expected to bring heavy rains and strong winds to east-central India over the weekend as well.
NOAA announced this week that it will host a press conference next Thursday, October 16th to discuss and delineate the winter season outlook for the USA. Several scientists from the Climate Prediction Center will be present to lead the discussion and answer questions.
The NOAA Climate.Gov newsletter also announced this week a webinar on October 16th to discuss "Climate Change and National Security." This will take place at Ohio State University and offer perspectives on how climate change may impact humanitarian relief efforts and armed conflicts.
A recent study by the University of British Columbia finds that a changing climate will have significant effects on the redistribution of fish stocks causing many species to migrate from the tropical latitudes toward the polar latitudes. This will be detrimental to the subtropical countries and cultures that rely on certain fish stocks for their basic dietary needs. There will be new opportunities for fisheries development in more Arctic regions of the ocean basins.
MPR listener question:What are the all-time October temperature extremes for Minnesota and what is the last date that a 90 degrees F temperature has ever been recorded this month?
Answer:The all-time extremes for October in Minnesota are 98 degrees F at Beardsley (Big Stone County) on October 5, 1963 and -16 degrees F at Roseau (Roseau County) on October 26, 1936. The latest date for a 90 degrees F reading in the Twin Cities is 90 F on October 10, 1928, while the latest date for the state is a reading of 90 degrees F at Canby (Yellow Medicine County) on October 30, 1950.
Twin Cities Almanac for October 10th:The average MSP high temperature for this date is 62 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 42 degrees F (plus or minus 9 degrees F standard deviation).
MSP Local Records for October 10th:
MSP weather records for this date include: highest daily maximum temperature of 90 degrees F in 1928; lowest daily maximum temperature of 38 degrees F in 1906; lowest daily minimum temperature is 25 degrees F in 1964 and 1987; highest daily minimum temperature of 63 F in 1930; record precipitation of 1.89 inches in 1898; and record snowfall 2.5 inches of snow fell on this date in 1977.
Average dew point for October 10th is 41 degrees F, with a maximum of 67 degrees F in 1949 and a minimum of 15 degrees F in 2009.
All-time state records for October 10th:The state record high temperature for this date is 93 degrees F at Tracy (Lyon County) in 1928. The state record low temperature for this date is 6 degrees F at Big Falls (Koochiching County) in 1932. State record precipitation for this date is 6.13 inches at Vesta (Redwood County) in 1973; and the state record snowfall for this date is 10.0 inches at Oklee (Red Lake County) in 1970.
Past Weather Features:October 10, 1928 was the warmest in state history with over 20 communities reporting daytime highs of 90 degrees F or greater. With winds from the east, north shore areas of Minnesota along the Lake Superior shoreline remained in the 50s F all day.
October 9-12, 1932 was cold and snowy. Many communities reported overnight lows in the 20s and 30s F, while daytime highs did not reach higher 50 degrees F at many places. Snowfall was widespread ranging from trace amounts in most places and from 1 to 2 inches at a number of southern locations.
October 9-10, 1970 brought even more widespread snowfall to the state. Many counties reported 3-5 inches, while Fosston reported 9 inches and Slayton reported 7.5 inches. The snow was short-lived and melted over a few days.