February similar to January temperature pattern:Just like January, the month of February started with warmer than normal temperatures which prevailed over most of the first week of the month. Now the mid month period is bringing single digit and below zero F readings, colder than normal temperatures. But like January, this will be followed by warmer than normal temperatures during the second half of the month. Mid-week low temperatures around the state were sub-zero in many areas, including -25 to -35°F at a few northern locations (including -35°F at Cotton and -32°F at Embarrass).
For January and February of 2016 so far the frequency of sub-zero F temperatures is less than average. Here are the average number of sub-zero nights per month for selected Minnesota climate stations with the number of nights measured so far in 2016 (through February 12) shown in parentheses......
January: Duluth 11 (1); International Falls 16 (14); Embarrass 18 (12); Saint Cloud 14 (9); MSP Airport 11 (9); Rochester 10 (9)
February 1-12: Duluth 11 (6); International Falls 12 (5); Embarrass 15 (5); Saint Cloud 10 (2); MSP Airport 7 (0); Rochester 6 (2)
Recall just two winters ago these cities had the following number of sub-zero F nights during January and February of 2014: Duluth 42; International Falls 45; Embarrass 51; Saint Cloud 41; MSP Airport 36; Rochester 37.
February 7-8 brought blizzard conditions to many parts of southwestern and south-central Minnesota, but without the heavy snowfall that the February 2-3 blizzard brought. Nevertheless despite the lighter snowfall amounts some schools and roads were closed in southwestern counties. Over the first 12 days of the month many observers have reported from 4 to 12 inches of snowfall, on course to post a snowier than normal month. Over the past 10 years February has brought above normal snowfall seven times to most observers around the state, so this year may be following that trend.
Modest soil frost depths:This winter season started late and has mostly brought above normal temperatures, despite the cool trend of this week. In addition much of central and western Minnesota has recorded snow cover of at least a few inches. As a result soil frost depths are not as deep as normal for this time of year. Sampling frost depths from around the state this week shows 12 inches at Waseca and Morris; 8 inches at Lamberton and St Paul, and just 6 inches at Pipestone. Normally this time of year would bring frost depths ranging from 25 to 35 inches. Given the current situation frost may leave the soil earlier than normal in the spring this year.
Weekly Weather Potpourri:With a nod to this weekend's Valentine's Day, NOAA issued an interesting article on climate and chocolate on their climate.gov web site this week. The premise for this article is that growing regions around the world are likely to shift around due to climate change, and this could have an impact on the quantity and quality of the cocoa bean used to make chocolate.
Also this week the NOAA-Climate Prediction Center announced new online tools to examine their climate outlook maps and products. These new tools offer better quality maps and allow for easier access to different time periods ranging from 3-7 days out to as far 12 months ahead.
Earlier this week came a new study about how climate change might affect trans-Atlantic flight travel. This study by Paul D. Williams was released in Environmental Research Letters. Based on climate model projections there will be an increase in the mean wind speeds in the polar jet stream, that blows west to east aloft over the North Atlantic Ocean. Using an expected increase in mean wind speed of about 15 percent, this will shorten the typical air travel time between New York and London to 5 hours and 20 minutes. Conversely it will increase the travel time between London and New York to about 7 hours. More details appear at the Science Daily web site.
According to the Joint Typhoon Warning Center (JTWC), there were three tropical cyclones in the southern oceans this week, but only one was expected to gain significant strength. Tropical Cyclone Winston is expected to produce wind speeds up to 140 mph this weekend and wave heights over 40 feet. It is tracking west of the Polynesian kingdom of Tonga in the South Pacific Ocean and may bring heavy rains and high seas there early next week.
MPR listener question:Last week I read your remarks about the coldest ever temperature in Minnesota, -60°F at Tower on Groundhog's Day (Feb 2) of 1996. My wife and I were wondering what was the high temperature that day, and was that a record as well?
Answer:The high temperature at Tower on February 2, 1996 was -16F which is also the record coldest maximum temperature for February 2nd at that location. The statewide record coldest maximum temperature was also set that date at Hallock (Kittson County), Minnesota with an afternoon high of -31F (after a morning low of -46F). This was one of the coldest maximum temperatures ever measured in state history, the coldest being -39F at Roseau on February 8, 1899 (after a morning low of -45F). February 9, 1899 was actually the coldest day in Minnesota history with an average temperature at Detroit Lakes of -43.5F (low of -53 and high of -32F).
Twin Cities Almanac for February 12th:The average MSP high temperature for this date is 28 degrees F (plus or minus 12 degrees F standard deviation), while the average low is 12 degrees F (plus or minus 15 degrees F standard deviation).
MSP Local Records for February 12th:
MSP weather records for this date include: highest daily maximum temperature of 59 degrees F in 1990; lowest daily maximum temperature of -5 degrees F in 1905 an 1936: lowest daily minimum temperature is -30 degrees F in 1875; highest daily minimum temperature of 34°F in 1908, 1928, and 1984; record precipitation of 0.42 inches 1984; and record snowfall of 3.2 inches in 1940 and 1965.
Average dew point for February 12th is 11 degrees F, with a maximum of 37 degrees F in 1984 and a minimum of -28 degrees F in 1967.
All-time state records for February 12th:The state record high temperature for this date is 63 degrees F at Windom (Cottonwood County) in 2005. The state record low temperature for this date is -50 degrees F at Roseau (Roseau County) in 1914. State record precipitation for this date is 1.86 inches at Brainerd (Crow Wing County) in 1922; and record snowfall is 17.0 inches at Fairmont (Martin County) in 1965 and at Orwell Dam (Otter Tail County) in 2013.
Past Weather Features:Arctic high pressure produced the coldest ever February 12th in 1914. At least 17 Minnesota climate stations reported a morning low of -40°F or colder. Snow cover ranged from 8 to 20 inches for mid February of that year, and it was one of the coldest months of February in state history.
February 9-12, 1965 brought heavy snows to Minnesota with many observers reporting from 10 to 20 inches of snow. Some schools in central and southern Minnesota counties were closed as a result of the heavy snows.
A mid February rain storm came to the state over the 11th and 12th in 1984, bringing amounts ranging from a half inch to one inch of rain. A few southern Minnesota observers reported hearing a little thunder as well.
The warmest February 12th in state history occurred in 1990, enhanced by the relative absence of snow cover across southern portions of the state. Most observers in central and southern Minnesota saw afternoon temperatures climb into the 50s F, while 10 cities reported a high temperature of 60°F or higher.
February 10-12, 2013 brought blizzard conditions and heavy snows to parts of western Minnesota. Rothsay (Wilkin County) reported 21 inches of snow, and for a time portions of I94, Hwy 10, and Hwy 210 were closed because of poor visibility from blowing and drifting snow.
Very cold to start the weekend, then increasing cloudiness late on Saturday with an increasing chance for snow. Snow and blowing snow on Sunday, but with warming temperatures. Lingering snow in the northeast counties on Monday morning with a warming trend starting on a statewide basis. Chance for snow again Tuesday and Wednesday, followed by a stronger warming trend over Thursday through Saturday next week, as temperatures rise to above normal levels.