Skip to main content

Disparity in Winter Temperature Signal Associated with Snow Cover

Disparity in Winter Temperature Signal Associated with Snow Cover:


Last week I stated that this winter (Dec-Feb) will end up being colder than normal for most places in the state, something that has been fairly rare in occurrence over the past three decades. Approximately 90 percent of the climate stations in Minnesota will end up with an average temperature for the December (2017) through February (2018) period that is colder than average. Only about 10 percent of Minnesota’s climate stations will show a mean winter temperature that is slightly warmer than normal.

Areas of the state with ample snow cover will show the largest negative temperature departures, while areas that have been deficient in snow cover all winter will show slight positive temperature departures. Embarrass (St Louis County) which has reported significant snow cover since mid-December has reported 9 dates with a low temperature of -40 degrees F or colder. Conversely, Montevideo (Chippewa County) which has had only traces of snow cover all winter has reported 17 days with temperatures of 40 degrees F or higher.

In terms of the snow season, northern Minnesota is the place to be if you like snow for recreation. Only Isabella, Ely, Two Harbors, Wolf Ridge (near Finland, MN), and the uplands outside of Grand Marais have reported over 60 inches of snow since October of last year. Isabella (Lake County) has reported 76 inches, most in the state. Conversely many western counties including Douglas, Swift, Renville, Traverse, and Big Stone have reported less than 10 inches since last October, and a handful of stations have reported less than 6 inches, a real snow drought.

Weekly Weather Potpourri:

NOAA released this week a summary of the global climate pattern for January 2018. It was the 5th warmest January globally for the record period going back to 1880. January of 2018 was also the 397th consecutive month (back to 1985) where the average global temperature has exceeded the 20th Century average. They also highlight other climate attributes for the month.

A recent video from the Yale Climate Forum provides a discussion of how climate change is affecting extreme weather around the world. The scientists interviewed describe how increasing temperatures in the Arctic are affecting the path of the jet stream, the severity of storms, and the length of individual weather events (rain, storms, drought).

A recent paper in the journal Nature Communications describes how changes in Earth’s vegetation composition of had significant effects on climate behavior, making some areas warmer and some areas drier. Most of the climate effects are brought about by changes in the radiation balance at the Earth’s surface.

A recent paper in Reviews of Geophysics documents how tides affect the loss of ice in both the Greenland Ice Sheet and Antarctica. Tides and their actions are in turn affected by climate change, as with changes in sea level and coastlines caused by climate change in turn affect the magnitude and timing of tides.

MPR listener question

Here at Milan, MN (Chippewa County) we have received only 9 inches of snowfall since last fall, and only 1 inch so far in February. Do you know what the record lowest total amount is for the snow season here at Milan? If anybody does, we thought it would be you.

Answer:

Over the past 125 years at Milan the smallest amount of snow for a snow season (Sept-May) was in 1930-1931 when only 7.5 fell. The second lowest total was 8.4 inches in 1941-1942, and the third lowest total was 11.9 inches in 1920-1921. So if you receive no more snowfall until May, this season would rank third lowest. But that is unlikely with so much snow in the forecast over the next several days. In fact according to National Weather Service forecasts you could receive several more inches before the end of this month.

Twin Cities Almanac for February 23rd:

The average MSP high temperature for this date is 32 degrees F (plus or minus 12 degrees F standard deviation), while the average low is 16 degrees F (plus or minus 13 degrees F standard deviation).

MSP Local Records for February 23rd:

MSP records for this date include: highest daily maximum temperature of 59 degrees F in 1958; lowest daily maximum temperature of -8 degree F in 1889; lowest daily minimum temperature of -25 degrees F in 1889; highest daily minimum temperature of 40 degrees F in 1931; record precipitation of 0.63 inches in 1909 and 1977. Record snowfall on this date is 6.3 inches in 1909.

Average dew point for February 23rd is 15 degree F, with a maximum of 45 degrees F in 2000 and a minimum of -23 degrees F in 1967.

All-time state records for February 23rd:

The all-time state high temperature for today's date is 70 degrees F at Lake Wilson (Murray County) in 2000; the all-time state low for today's date is -43 degrees F at St Vincent (Kittson County) in 1889. The all-time state record precipitation for this date is 2.35 inch at Detroit Lakes (Becker County) in 1922. Record snowfall is 25.0 inches at Detroit Lake (Becker County) also in 1922.

Past Weather Features:

With over a foot of snow on the ground already a bitter cold Arctic air mass settled over the state on February 23, 1889 bringing record-setting cold to many places. Some of the low temperatures included -43 degrees F at St Vincent (Kittson County), -35 degrees F at Moorhead, -34 degrees F at Morris, -30 degrees F at Duluth, and -25 degrees F in the Twin Cities. The temperature at Moorhead that day never climbed higher than -13 degrees F.


A powerful winter storm brought a mixture of rain, sleet, and snow to the state over February 22-23, 1922. At Willmar 3.23 inches of precipitation was recorded (a record amount for February), with 14 inches of snow. Many observers reported 6-12 inches of snow, but Mora and Detroit Lakes reported over 20 inches.


Another winter storm brought mixed precipitation to the state over February 23-24, 1977. Some areas of the state reported over 2 inches of precipitation, while many observers also reported 7-14 inches of snowfall.

By far the warmest February 23rd in state history was in 2000 when most communities in the state reported afternoon high temperatures in the 50s F. In fact at least a dozen climate observers reported a high of 60 degrees F or greater, topped by 70 degrees F at Lake Wilson in Murray County.

Yet another slow moving winter storm brought a mixture of precipitation to the state over February 23-25, 2001. Many observers reported new daily snowfall records on those dates. Many climate stations reported from 10 to 20 inches, with the north shore of Lake Superior receiving over 20 inches.

Outlook


The weekend will start out relatively mild, but increasing cloudiness on Saturday will eventually bring snow to most of the state over the late afternoon and evening. In eastern sections of the state snow may linger into early Sunday morning. Widespread coverage of snow may lay down areas of 6 to 10 inches. Beginning on Monday milder temperatures will prevail for much of next week under partly cloudy skies, with a change for snow again late Wednesday and into Thursday.



Comments