At Last, Some November Precipitation

At Last, Some November Precipitation:

After nearly two weeks without any measurable precipitation for most parts of Minnesota, a large low-pressure system brought widespread rainfall over November 10-12. Some areas of northern Minnesota reported 3-5 inches of snowfall as well, with Warroad reporting 6 inches and Chisholm reporting 6.7 inches. More snowfall is expected this weekend later on Saturday.

Many areas reported from half an inch to one and a half inches of rainfall. In southeastern Minnesota observers in Mower, Fillmore, Winona, Wabasha, and Houston Counties reported over an inch and a half of rainfall. And in northeastern Minnesota around Grand Marais and Hovland (Cook County), they reported well over two inches of precipitation. Some climate stations actually reported new daily record amounts of rainfall (mostly for November 11th), including:
Brainerd 0.84”
Hallock 0.86”
Rosemount 0.90”
Floodwood 0.95”
Thief River Falls 1.09”
Zumbrota 1.14”
Lake City 1.24”
Wabasha 1.30”
Austin 1.31”
La Crescent 1.35”
Spring Valley 1.46”
Theilman 1.52”
Minnesota City 1.54”
Grand Meadow 1.85”

Much of this rain fell at rates that could be easily absorbed by the soil, which is yet unfrozen. Undoubtedly too the rain will help reduce the area of Minnesota that is still in Severe to Extreme Drought, an area currently estimated to be about 29 percent of the landscape.

The National Weather Service had to issue a Winter Weather Advisory for portions of northern and western Minnesota on Thursday, November 11th as some accumulating snow was expected on the backside of the storm system. In addition, because of wind gusts over 35 mph portions of extreme west-central Minnesota were issued a blizzard warning for late Thursday and early Friday.

Ralph Abercromby - meteorologist and photographer:

During the 1870s there was increasing use of photography in scientific investigations. In meteorology, one of the pressing needs was to photograph cloud forms and publish a cloud atlas which would illustrate the cloud classification system proposed by Luke Howard in 1802 and also serve as a reference for people to use when making daily weather observations which often included sky cover, cloud types and estimated cloud heights. Up until that time, drawings and sketches of cloud forms had served as observational guidelines for classifying cloud types.

To meet the need of the international meteorological community, English photographer Ralph Abercromby made a series of voyages around the world from 1884 to 1886 with the express purpose of taking as many pictures of different cloud forms as he could find. His camera was bulky and unwieldy, using large gelatin plates to capture the images. By 1887 his collection was large and diverse, enough to publish the first cloud atlas using photographs.

Today, the modern International Cloud Atlas published by the World Meteorological Society not only contains color photos of cloud types taken from observers on the ground, but also images taken from airplanes and orbiting satellites. A comprehensive photo array of cloud types and descriptions is also available to the public online from the Cloud Appreciation Society, of which I am a member.

Weekly Weather Potpourri:

According to Science Daily a recent research report from the University of Illinois illustrates how some rops that experience drought conditions and/or extreme temperatures during early growth stages and survive are better able to deal with those same conditions later in their development cycle. Such growth behavior helps mitigate yield reduction, and if tied to genetics may help plant breeders create more resilient crops to cope with climate change.


This week’s AGU-EOS bulletin features an interesting article about receding tropical glaciers (caused by climate change) and the impact on local landscapes and cultures, especially in South America. Many communities are dependent on the seasonal runoff from glaciers to provide their water supply, and accelerated efforts to adapt to climate change will be needed.

MPR listener question:

Earlier this fall you remarked on MPR’s Morning Edition that some parts of northern Minnesota caught in the bullseye of the Drought were recording one of their driest years ever. With the additional rain across the state this autumn is that still the case?

Answer:

Yes, there are many places in Minnesota that have reported less than 18 inches of precipitation so far this year, mostly in northern counties. A sampling is listed below of the year-to-date precipitation totals and the approximate percentage of normal they represent (through November 11th):
Bemidji (Beltrami County) 14.42” about 57 percent of normal
Crookston (Polk County) 14.48” about 68 percent of normal
Warroad (Roseau County) 14.55” about 61 percent of normal
Lake Bronson (Kittson County) 15.09” about 72 percent of normal
Kabetogama (St Louis County) 15.74” about 63 percent of normal
Hawley (Clay County) 16.96” about 63 percent of normal
International Falls (Koochiching County) 17.33” about 73 percent of normal

It is likely that many of these locations will finish the year 2021 ranking among the driest 10 years historically, unless the final 7 weeks of the year are exceptionally wet (unlikely).

Twin Cities Almanac for November 12th:

The average MSP high temperature for this date is 44 degrees F (plus or minus 11 degrees F standard deviation), while the average low is 29 degrees F (plus or minus 10 degrees F standard deviation).

MSP Local Records for November 12th:

MSP records for this date: highest daily maximum temperature of 65 degrees F in 2001; lowest daily maximum temperature of 11 degrees F in 1940; lowest daily minimum temperature of -4 degrees F in 1966; highest daily minimum temperature of 44 degrees F in 2005; record precipitation of 0.90 inches in 1965. Record snowfall is 8.5 inches in 1940.

Average dew point for November 12th is 26°F; the maximum dew point on this date is 53°F in 2005; and the minimum dew point on this date is -9 degrees F in 1986.

All-time state records for November 12th:

The state record high temperature for this date is 74 degrees F at Faribault (Rice County) in 1923. The state record low temperature for this date is -26 degrees F at Tower (St Louis County) in 1995. The state record precipitation for this date is 2.62 inches at Schroeder (Cook County) in 1940. Record snowfall is 16.0 inches at Farmington (Dakota County) in 1940.

Word of the Week: Freezing Level

This is a term used in meteorology to refer to the lowest altitude in the atmosphere over a given location at which the air temperature is 32 degrees F (0 degrees C). In other words, the height of the 32°F airstream overhead. It is highly variable and changes markedly with the seasons in Minnesota. In summer it might be as high as 10,000 ft, while in winter it comes right down to the ground at times. Average height of the freezing level at MSP during the first week of November is about 3200 ft, but by the end of the month it is about 1200 ft. These changes can be substantial even over a day. For example, the freezing level above the Twin Cities on Wednesday morning, November 10 this week was 6500 ft, but by Thursday morning (November 11th) it had dropped to 4100 ft. 

The change in average freezing level during the month of November is associated with a number of other significant changes in climate during the month including: over a 1 hour reduction in daylength (over 10 hrs to just over 9 hrs); an 18 degree F decline in daily mean temperature (from 42°F to 26°F); an increase in cloudiness; and a increase in the occurrence of freezing precipitation (freezing rain, sleet, snow).

Past Weather Features:

The famous Armistice Day Blizzard occurred over November 11-12, 1940 paralyzing much of eastern Minnesota with blinding heavy, wet snow, accompanied by a severe temperature drop. Forty-nine people, including many duck hunters, lost their lives during the storm. Many parts of the state reported snowfall totals ranging from 12-24 inches. In addition up to 20 foot drifts closed many highways and blocked railroads from moving.

November 12, 1941, the year after the Armistice Day Blizzard, most of Minnesota reported a lovely, sunny afternoon with temperatures in the 50s and 60s F. It even reached a record 70°F at Beardsley (Big Stone County).

Very cold temperatures prevailed across Minnesota on the morning of November 12, 1966. Most areas of the state reported subzero temperatures ranging from the single digits to teens below zero. Portions of Itasca, St Louis, and Lake of the Woods Counties were -20°F or colder. The high temperature at Argyle (Marshall County) only reached 10°F.

Outlook:

Cloudy and much cooler weather over the weekend, with a chance for snow on Saturday afternoon and evening. Continued colder than normal temperatures for Sunday and Monday, with chances for snow in northern sections of Minnesota. A brief warming on Tuesday, then mostly cooler than normal and dry for the balance of next week.