April 2010 Saint Cloud Weather Summary

Warmest April in 95 Years

Warmest Start to Spring in a Century

While the early part of the cold season of 2009-2010 was quite cold, April 2010 continued the very warm trend seen since the rapid snowmelt in March. The April average temperature at the Saint Cloud Regional Airport was 51.1°F, 7.5°F warmer than normal. This made April 2010 the third warmest April among the 130 Aprils in St. Cloud records. It was the warmest April since 1915, the warmest April in St. Cloud. April 2010 came right on the heels of the third warmest March in St. Cloud records. So far, the spring of 2010 (March and April combined) has had an average temperature of 44.4°F, the second warmest March-April average and the warmest in a century. Only March and April of 1910 (46.7°F) was warmer.

5th Warmest April High Temperature

The April 2010 average high temperature in St. Cloud was 64.3°F, more than nine and a half degrees warmer than normal. This was the fifth warmest April high temperature on record. Temperatures were warmer than normal in 28 of the 30 April days with 10 days having temperatures at least 10 degrees warmer than normal. In a month when the average high temperature doesn't get to 60 degrees until April 24, there were only 6 days when the high didn't break 60. There were 7 days with a high of 70 degrees before the average day of the first 70-degree high, April 30.

Closing In for One of Fewest Freezing Days

There were only 7 days with a low of freezing or lower in April 2010. That brings the number of sub-freezing lows to 150 days so far during the cold season, 18 days fewer than normal. That means that the cold season of 2009-2010 could break into the fewest days with a low of at least 32 degrees. The record is 152 days, set in 1899-1900 and tied in 1924-1925. Normally, there are 3 days with a low of freezing or colder. The average last day with a frost is May 18.

Early Snowmelt, Sunny April Contribute to Warmth

The reason for the warm temperatures were twofold: first, the early snowmelt. Since the ground went bare on March 14, there have only been 4 days with below normal temperatures. The early loss of the snow cover was widespread in not only the Northern Plains, but also the Canadian Prairie Provinces, according to NOAA's March 2010 State of the Climate report. That's because it was more abnormally warm in the Canadian Prairie Provinces during March than it was in Minnesota. No snow cover in April to our north means that it's much harder to produce cold air masses to move into Minnesota. Any really cold air that tried to move southward began losing its punch over Saskatchewan, Alberta, and Manitoba, long before it could reach Minnesota.

The lack of snow cover meant that there was no measurable snow during the month of April in St. Cloud. That's only the 11th April since snowfall records began in 1899 with no April snowfall. In fact, the last day with measurable snow was February 13. So, the final St. Cloud 2009-2010 cold season snowfall was 30.8 inches, 17 inches less than the normal snowfall of 47.8 inches.

The other reason for the warm, daytime temperatures was the amount of sunshine. Twenty-nine of the 30 April days ranked as being clear (21 days) or partly cloudy (8 days).

April Warmth Throughout Area

The warmth was very widespread, since Minneapolis-St. Paul had its second warmest April on record and tied for the warmest March-April, Duluth had its warmest April on record, International Falls had its 5th warmest April, and Rochester had its second warmest April. Preliminary data shows that temperatures throughout Minnesota, Iowa, and Wisconsin ranked in the five warmest Aprils.

Dry Conditions Cause Wildfire Problems

The warm weather was accompanied by a lack of precipitation. Only 1.43 inches of rain fell in St. Cloud during April 2010. This was 0.70 inches less than normal. Rainfall was very hit and miss during the month of April, since the few chances at thunderstorms produced some large amounts of rainfall in some areas and very little rain in others. The St. Cloud Airport got most of its rain during the thunderstorms on April 13, when 0.90 inch fell, setting a daily precipitation record. Since the end of the last major rainstorm on March 12 through the end of April, the St. Cloud Airport has picked up only 1.45 inch. The normal rainfall for that period is 3.45 inches. The area that got the most rain in April was the southwestern suburbs of the Twin Cities with a swath of more than 2 inches of rain from southwestern Minnesota through Redwood Falls and the Twin Cities, then northward through Cambridge and Milaca. From St. Cloud north and westward, less than an inch and half has fallen since the snow cover left with little or no precipitation in the northern third of the state.

The lack of rain already ranks as a severe drought in the Arrowhead of Minnesota, according to the latest National Drought Monitor from the Drought Mitigation Center. The area of moderate drought spreads from Lake of the Woods across northern Minnesota and along the Wisconsin border southward to the northeastern Twin Cities Metro.Abnormally dry conditions extend from St. Paul through eastern Sherburne and Benton Counties and most of Morrision County to the Northwest Angle.

The lack of rain coming on the heels of the rapid snowmelt produced periodic outbreaks of grass and wildfires. For the year, the Minnesota DNR Division of Forestry wildfire map shows over a thousand fires, most of them from St. Cloud northward and east of the Mississippi from the northern Twin Cities northward. There have over 25,000 acres burned by the wildfires. That's already more acreage burned than either of the past two years. Dry conditions on the heels of the snowmelt are not unusual for April. On the average, there are far more wildfires in April than during any other month.

The lack of rain was mostly caused by a split in the steering winds across North America. The polar storm track stayed mostly in Canada, keeping any cold air locked up in far northern and eastern Canada. The subtropical storm track stretched across the southern US, keeping any deep moisture locked up across the southern third of the country. Minnesota was in between, keeping us mostly mild and dry.

Late Start to Severe Weather Season Clobbers Deep South

This weather pattern also produced a lack of severe weather nationwide. The number of severe weather reports were far below normal until the late April storm system that produced long-track tornadoes over the Deep South. This included one tornado that stayed on the ground for over 140 miles in Louisiana and Mississippi. There were other deadly tornadoes in Alabama.

April 2010 Statistics