Record warmth abruptly ends:The record-setting warmth of the first 17 days of November (temperatures 13-15°F above normal) abruptly ended this week with a strong winter storm which ushered in widespread precipitation, some heavy snow, very strong winds, and cold air. For the first time since mid-October many communities will see their first below normal temperatures over this coming weekend, and central and northern Minnesota will receive the first significant snowfall, with many western counties under a blizzard warning. Although this weather event will bring an end to the historically warm pattern it is likely that with moderating temperatures for the balance of November, we will end up with one of the warmest Novembers in state history. In addition much of the model guidance suggests that the first ten days of December will be warmer than normal as well.
One additional note to add on the first half of November comes from Dave Ruschy, who for many years managed the St Paul Campus Climate Observatory. He recently noted that the first two weeks of November brought near record solar radiation. With absence of cloud cover solar radiation measured in the Twin Cities area during the first half of November was over 40 percent above average and very near the record sunniest of November 1981. Solar energy measurements at the St Paul Climate Observatory date back to 1963. This climate feature certainly affected the warm statewide pattern and helped keep soil temperatures around the state well above normal.
Winter storm brings first significant precipitation of the month:A winter storm (Thursday through early Saturday) this week brought the first significant precipitation of the month for many climate stations in the state, and for some the first significant amount since October 29th. Precipitation fell in the form of rain, sleet, and snow. Observers reported liquid amounts ranging from a quarter of an inch to three-quarters. With unfrozen soil conditions, much of the precipitation will infiltrate the soil and be stored there for the winter. In addition soil temperatures will begin to decline in earnest following the winter storm, so those who have been waiting to apply mulch to the garden may want to do so next week. Stored soil moisture is abundant and quite adequate over most parts of the state. This moisture will still be there come next spring when the agricultural and gardening season begins.
This winter storm delivered significant precipitation to the state, and it appears that another storm may deliver more precipitation next Tuesday and Wednesday before Thanksgiving.
New seasonal climate outlook:The NOAA Climate Prediction Center released a new set of seasonal climate outlooks this week. Although the first ten days of December are expected to be warmer than normal, the temperature outlook for December through February leans toward cooler than normal temperatures across the state. In fact cooler than normal temperatures are expected across the region through April of 2017. I remain skeptical about this outlook and have little confidence in it.
For the period from December through April the outlook for precipitation favors above normal values across the Great Lakes Region, including Minnesota. Given the recent historical trend for wetter than normal conditions, this outlook is compatible with the evidence in Minnesota.
Weekly Weather Potpourri:Timely this week with the onset of snow cover over the Minnesota landscape, NOAA featured a review of its monitoring program for snow and ice cover maps of the USA. These are updated daily and might be useful for the winter season in planning travel and outdoor recreational activities.
EOS this week featured an interesting article about how climate and humans have responded to past significant volcanic eruptions. It is an interesting read is still relevant to climate behavior today.
The NOAA Climate Resilience Toolkit this week features an article about using historical rainfall analysis to properly size culvert design for roads and trails. The climate data to use for such purposes is now more available than ever.
A recent paper published in the International Journal of Climatology documents changes in monsoon rainfalls in India. The records show that heavy rainfalls during the monsoon season are becoming greater in intensity (amounts) as well covering a larger geographic area of central India. The frequency, areal coverage, and intensity of hot days during the monsoon season also show increases.
BBC Weather Centre reported this week on rare November tornadoes which brought damage to parts of Wales and the English Midlands. Relatively small in scale and short-live these storms knocked down trees and caused some structural damage to buildings.
MPR listener question:Is it unusual for the first major snowfall of the season to come as a blizzard to many parts of the state. Don't we usually start winter a little more gradually?
Answer:Yes, more often than not winter settles in first with a few small doses of snowfall spread out over several weeks. But an abrupt start with an early season blizzard has occurred a number of times in our history. Some examples in our history include:
October 16-18, 1880 paralyzing blizzard in SW Minnesota
October 19, 1916 blizzard delivered 7-12 inches with 5 ft drifts in northwestern and north-central MN
November 11, 1940 Armistice Day Blizzard, first snow of the season for most of the state
October 31-November 2, 1991 Halloween Blizzard was first snowfall of the season for eastern MN
November 15-17, 1996 blizzard delivered first snow of the season to west-central MN
November 11, 1998 blizzard delivered over a foot of first snow cover to Yellow Medicine County, MN
October 24-25, 2001 a blizzard delivered over a foot of first snow cover to many areas of the Red River Valley, MN
Twin Cities Almanac for November 18th:The average MSP high temperature for this date is 40 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 25 degrees F (plus or minus 10 degrees F standard deviation).
MSP Local Records for November 18th:
MSP weather records for this date include: highest daily maximum temperature of 68 degrees F in 1904 and 1941; lowest daily maximum temperature of 13 degrees F in 1874; lowest daily minimum temperature is -4 degrees F in 1891; highest daily minimum temperature of 53 degrees F in 1953; record precipitation of 0.82 inches in 1981; and a record snowfall of 7.6 inches in 1957.
Average dew point for November 18th is 26 degrees F, with a maximum of 56 degrees F in 1941 and a minimum of -2 degrees F in 1989.
All-time records for November 18th:The state record high temperature for this date is 75 degrees F at Faribault (Rice County) in 1923. The state record low temperature for this date is -19 degrees F at Duluth (St Louis County) in 1940. State record precipitation for this date is 3.10 inches at Hinckley (Pine County) in 1996; and record snowfall is 15.0 inches at Crookston (Polk County) in 1998.
Past Weather Features:November 18, 1874 was clear and cold. The few climate stations in the state at that time reported morning lows near zero degrees F and afternoon highs only in the teens.
The coldest statewide November 18 occurred in 1914 following a winter storm which dumped several inches of snow across many parts of the state. Many climate stations in central and northern Minnesota reported subzero low temperatures, and single digit temperatures were common in southern counties. The daytime temperature never rose above 11°F at Fergus Falls.
All-time warmest November 18th in history was in 1953 when most climate stations reported daytime highs in the 60s F. Ten communities saw the mercury climb into the 70s F including Detroit Lakes (Becker County). No sign of winter was yet in the air.
November 16-18, 1958 brought a major winter storm to the state. A mixture of rain, sleet, snow, and ice fell across the state making travel very difficult. Some communities in southern Minnesota reported over 2 inches of rain, while in the far north over 10 inches of snow was reported.
Heavy snow fell across the northern counties of Minnesota over November 16-19, 1998. Many areas reported over 10 inches and a number of roads and highways were closed for periods of time. High winds blew snow into large drifts as well.