December 2011 Saint Cloud Weather Summary

Saint Cloud Weather Summary for December 2011 and Annual Weather Summary for 2011

    December 2011 Statistics

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From Buried to Barren
2011 Annual Saint Cloud Weather Summary

2011 ended up with near normal temperatures and precipitation, but it was a case of extremely wet and white weather for most of the first seven months, then extraordinarily dry and mild weather during the last 5 months.

2011 Precipitation

The total 2011 St. Cloud precipitation was 28.05 inches, within 0.3 inch of normal. The total snowfall in the calendar year stands at 48.2 inches, 2.1 inches above normal.

Early 2011 Snowy, Leading to Flooding

The start of year saw the continuation of an extraordinarily snowy cold season of 2010-2011. There were 66.1 inches of snow, the 8th snowiest cold season of the 105 snow seasons in St. Cloud records and the snowiest since the 1978-1979 cold season. While December 2010 was the month with the most snow (21.0 inches), more than 10 inches of snow fell in January, February, and March. This was only the 6th cold season having 4 months with double-digit snowfall accumulations. The meteorological winter (December 2010-February 2011) was the 4th snowiest with 47.6 inches.

St. Cloud managed to dodge the heaviest snowfall from the major storms. There were between 60 and 90 inches of snow (light blue and purple dots on the NOAA 2010-2011 seasonal snowfall chart) from eastern South Dakota through southern Minnesota, but the snow totals tapered off from St. Cloud northward to the rest of Minnesota, except the Arrowhead. St. Cloud only got 5.3 inches from the storm that produced the Twin Cities heaviest December snowfall on record and got only 8.1 inches from the storm that produced Minneapolis-St. Paul's February record snowstorm. The highest single day snowfall was 5.5 inches on March 23, setting a record for daily snowfall.

The snow season was not only heavy; it was prolonged. St. Cloud had continuous snow cover from November 22 through April 1, marking 130 consecutive days with at least an inch of snow cover. That's the 8th longest stretch of continuous snow cover in St. Cloud records and only the 11th year in which the continuous snow cover didn't melt until April. As was the case with other recent years with late snow melt (1996-1997 and 2000-2001), the late snow melt produced record river flooding, especially in the Red River Valley. The Red River left its banks on March 27, peaked in Fargo at 38.75 feet, less than 1 1/2 feet below the record crest, and didn't get back below flood stage at all until early June. Thanks to more heavy rainfall during the first half of the warm season, the Red River did not fall below flood stage for good until August 27.

The frequent precipitation continued after the snow melted. Between April 1 and August 20, the St. Cloud Airport picked up 20.81 inches, nearly 6 inches above the average amount of 14.90 inches.

2011 Severe Weather

While the severe weather season didn't reach the Minnesota record number of tornadoes in 2010, severe weather had its impact. The worst day statewide was the May 22, when three tornadoes touched down in Minnesota, including a tornado that moved through North Minneapolis, killing one person and injuring 48 others. That was the same day when an F5 tornado went right through Joplin, MO, killing 158 people, the worst death toll from a single tornado since records began in 1950.

(Note: Nationally, 2011 may have been the costliest weather year in US history with 12 events producing at least a billion dollars in damage. See summary from NOAA)

In the St. Cloud area, the worst storm was on July 1. The north and west side of the St. Cloud were hard hit by the windstorm that produced damage from Sioux Falls into northern Wisconsin with estimated wind gusts of 90-100 MPH in the Marshall, Lake Benton, and Redwood Falls areas. The tree damage in northern St. Cloud and Sauk Rapids was caused by a localized downburst that uprooted trees and produced 65-70 MPH wind gusts. There was also a small, brief tornado that touched touched down near the I-94/Hwy. 23 interchange and continued into western Waite Park near Division Street.

On May 10, a storm produced widespread large hail to the south and west of St. Cloud and a tornado near St. Michael.

On July 10, there was a storm that produced straight-line wind damage in parts of northern Stearns County, including Sauk Centre. Estimated wind gusts were 75-90 MPH. On July 30, there was wind damage and an EF-0 tornado in Mille Lacs and Isanti Counties and straight line wind damage in Bock.

There were also a couple of cases of flooding rain, including 2.40 inches on July 14-15. That storm set a record daily rainfall of 1.74 inches on July 15. The other locally heavy rain event was the June 21 rainstorm that mostly missed the St. Cloud Airport, but dumped over 2 inches of rain on the western side of St. Cloud and Waite Park.

Sudden Drying Late Summer Through December

During the dry period from August 20 through the end of the year, St. Cloud had only 3.29 inches, more than 6 inches short of the average of 9.61 inches. The dry conditions were the worst in northeastern Minnesota (more than 7 inches below normal) and the southern third of the state (8-10 inches below normal).

The main weather event that was enhanced by the dry conditions was the Pagami Creek Fire in the Western BWCA, which burned over 93,000 acres from late August through September. The dry conditions were made worse by strong winds near Labor Day took a small fire and spread it through a much larger area. Subsequent windy days with little rain kept the fire smoldering until the cold season began.

The early season lack of snow put only 6.7 inches down by the end of the year, compared to the average snowfall of 20.1 inches. In recent years, only the start of the 1980-1981 cold season (2.1 inches), the 2004-2005 cold season (2.2 inches) and the 2006-2007 cold season (2.7 inches) had less. Of those low snowfall years through the end of the December, only 1980-1981 ended up among St. Cloud's least snowiest cold seasons.

Ironically, the only major snowstorm that St. Cloud has had during the 2011-2012 cold season was the 3.9 inches on November 19. However, St. Cloud was at the southern edge of a heavy snowband that produced 8-11 inches from Rice, Sartell, and St. Stephen through Milaca to Mora. That amount set a daily snowfall record of 3.8 inches on November 19.

During the fall (September-November), only 2.39 inches fell, making it the fourth driest fall in St. Cloud records. September 2011 tied for the 4th driest with only 0.74 inch. There were only 17 days with measurable precipitation in the last 4 months of the year, the lowest total since 1952.

2011 Temperatures Also a Before and After

The change from wet first 7 months to dry last 5 months showed a similar change in temperature. Overall, 2011 had an average temperature of 43.7 degrees, 0.8 degree above normal. However, each of the first 5 months were colder than normal. We had a taste of summer on June 7 when the high climbed to 101°F, the third earliest 100-degree high in St. Cloud records. The only two earlier 100-degree highs were on May 28 and May 31 in 1934. After that, the high temperature never climbed higher than 78 degrees for the next three weeks.

July Dominated by Heat and Humidity

July was the rare month with both heat and rainfall. July 2011 tied for the 8th warmest July in St. Cloud records. The month featured the first 4-day heat wave (temperatures greater than 90 degrees) since September 2007. Conditions were extraordinarily humid as well, keeping St. Cloud's low temperature at 70-degrees or warmer for 5 straight days, the longest streak since 1955. July 2011 also featured record high dew points for Minneapolis-St Paul (82 degrees on July 19) and an all-time record for Minnesota (88 degrees in Moorhead). The highest dew point recorded in St. Cloud was 82 degrees on July 17 (see hourly readings from the Weather Underground), but there aren't any long-term dew point records in St. Cloud. How this compares to worldwide dew point records (highest on record surround the Persian Gulf) is discussed in this Weather Underground blog.

Warmest July-December since 1939

The fall and start of winter continued the mild trend with the last 6 months of the year all above normal. In fact, the last six months of the year averaged 52.4°F, the 5th warmest average for the second half of the year and the warmest since 1939.

In October, St. Cloud strung together its longest October streak of consecutive 80-degree highs, with 5 straight days between October 3 and October 7. In December, there were two record highs set and there were two highs above 45 degrees after December 18. Since 1940, there have been only 7 days with highs that warm so late in the year.