February Warmth and Wetness
(excerpted from Mark Seeley's "Weather Talk")

February turned record-setting during the third week of the month. Record-setting maximum temperatures settled across the region beginning on February 21. In fact, some places reported three or four consecutive days with record maximum temperatures. This was the result of strong warm air advection on southerly winds, the relative absence of abundant snow cover, and a February sun which is growing stronger each day. In addition to the numerous daily records broken that week, many places reported temperatures which tied or broke the all-time highs for the month of February. Some of those are listed below, most of which occurred on Feb. 22nd....

International Falls, MN 58 F
Crookston, MN 50 F
Crane Lake, MN 56 F
Warroad, MN 52 F
Grand Forks, ND 67 F
Devils Lake, ND 60 F
Roseau, MN 50 F (tied record)
Thief River Falls, MN 52 F
Hallock, MN 61 F (tied record)
Lamberton, MN 65 F
St James, MN 63 F (tied record)
Windom, MN 68 F

The temperature of 68 degrees F at Windom, MN (Cottonwood County) on February 22nd ranks as the third highest ever measured in the state during this month. The highest values of temperature measured during the month occurred on February 26, 1896 when Le Sueur reported 70 degrees F and Pleasant Mound (Blue Earth County) reported 73 degrees F. This warm advection event in 1896 brought high winds (30 to 50 mph) and a dust storm across the region. Omaha, NE reported a high of 78 degrees F and Vermillion, SD hit 79 degrees F. Thawed soils in southern MN continued to be blown around in March and some fields were planted very early. Active bees were observed during March of that year, an indication of how early spring arrived.

A storm system which passed over the region on February 23rd brought some record-setting rainfall amounts to some areas as well. Faribault, MN reported 0.51 inches, Sioux Falls, SD reported 0.77 inches, Spencer, IA 0.66 inches, and Kearney, NE 0.86 inches, all of which were new record amounts for the date. Many areas of southern and central Minnesota reported amounts ranging from 0.25 to 0.50 inches. Yankton, SD reported one of the highest amounts with 1.26 inches which was a record for the date as well. These significant rains in February are unusual (frequency about one year out of eight) and correspond with a warming trend observed in recent years. In fact this February may end up being ranked among the ten warmest statewide historically.

The warm temperatures and rainfall led to a remarkably rapid loss of snow cover across Minnesota. By week's end much of Minnesota was snow-free, an unusual condition for the end of February.

Remarkably high dewpoints were also reported the week of February 21. New dewpoint records were set throughout the week at the Twin Cities International Airport, topping out at 52 degrees on February 25. These dewpoints are more typical of mid-May and represent a large amount of water vapor in the atmosphere. The dense fog that formed as the result of the moist atmosphere led to school delays and closings, and created serious travel hazards.

Thunder was reported at some locations during this week as well. February thunderstorms are quite unusual, occurring in less than one per cent of all February days in the Twin Cities. A severe thunderstorm watch was issued for southwestern Minnesota on February 25. This is believed to be the only severe thunderstorm watch ever issued in Minnesota during February.

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URL: http://climate.umn.edu/doc/journal/warm_feb2000.htm
Last modified: February 28, 2000