June 2010 Saint Cloud Weather Summary

Wild Severe Weather Month in Minnesota, but St. Cloud Statistics Near Normal

Saint Cloud Weather Summary for June 2010

June 2010 will be remembered in Minnesota for the wild outbreak of severe weather during the final two weeks of the month, but the St. Cloud Regional Airport was frequently missed by the worst weather. The total rainfall at the St. Cloud Regional Airport was 4.92 inches, .41 inch above normal. Since the snow melted on March 12, the St. Cloud Airport has picked up 8.43 inches of rain, nearly two and a quarter inches short of the 10.66 inch average.

However, strong thunderstorms brought much heavier rain to nearby areas. According to the State Climatology Report on the wet spring, places like Paynesville, Clearwater, Clear Lake, Monticello, Big Lake, and Buffalo have gotten 7-9 inches of rain compared to the St. Cloud Airport's just short of 5 inches. Meanwhile, the Mankato area has picked up over 9 inches and parts of southeastern Minnesota got 10 inches of rain for the month. Most of this difference occurred during the week of June 22-28 with 3-6 inches of rain from southeastern Stearns County through northern Wright and most of Sherburne County, but less than half an inch fell from Royalton to west central Minnesota.

Still, it was the first month with above normal rainfall during the warm season. The rain wasn't always heavy over St. Cloud, but it was frequent. There were 16 days with measurable rainfall in June at the St. Cloud Airport, four days short of the 20-day record, set in 1914. There were 12 days with at least 0.10 inch of rain at the St. Cloud Airport, the third highest total in St. Cloud records. Because the St. Cloud Airport was not hit dead center by the thunderstorms, however, there still hasn't been a day with at least an inch of rain through the first 6 months of the year. That has only happened 15 times since St. Cloud rainfall records began in 1893.

The updated Minnesota Climatology Working Group report on the dry spring shows that only northeastern Minnesota is still being affected by drought conditions, as noted in the .Drought Monitor from the National Drought Mitigation Center. Rainfall deficits since the snow melt are still 2-4 inches in parts of Lake and Cook County. The problem is still worst with the drought is still at extreme levels (red color) in northeastern Wisconsin and the Upper Peninsula of Michigan. The only other part of the state with deficits that large are from Detroit Lakes to Morris, Benson, and Appleton.

Review of Wild Nine Days of Severe Weather

The frequent thunderstorms came with a lot of severe weather across Minnesota, in stark contrast to a relatively quiet start to the severe weather season, both in Minnesota and nationwide. The NWS Twin Cities Office has put out a review of the severe weather between June 17 and 26. During that time, there were 199 reports of severe weather in central and southern Minnesota and western Wisconsin, compared to 23 total reports before June 17.

June 17 was the worst day with 20 confirmed tornadoes, three of which produced EF-4 damage (wind estimates of 170-175 MPH) including the Wadena storm. The Wadena storm killed 3 people, the most tornado deaths in a single storm since July 5, 1978. The three EF-4 tornadoes were the most from a single storm since April 30, 1967, otherwise known as Black Sunday.

The National Weather Service also surveyed 7 tornadoes in southwestern and south central Minnesota from June 25. Storms did EF-2 damage near New Ulm and Courtland and in Blue Earth County. Winds were estimated at about 110 MPH in the New Ulm storm, 120-130 MPH in the Courtland storm, and 115-130 MPH in the 4 tornadoes that struck Blue Earth County. Also, the tornadoes that touched down in southwestern and south central Minnesota on June 25 were surveyed and rated EF-1 to EF-2. That day was more known for its widespread straight line damaging winds and the heavy rain that caused flooding.

On June 26, there was more heavy rain and flooding and uncomfirmed reports of 5 tornadoes.

So far in 2010, there have been 27 confirmed tornadoes in Minnesota, compared to the Minnesota annual average of 25.8 since 1950. The number of June tornadoes is already higher than the full-year tornado total for 2009 (24), 2007 (18), and 2006 (25).

Very few wind instruments could survive winds well over 100 MPH, so the Enhanced Fujita scale was created to estimate wind speeds based on the damage and engineering studies of the forces required to do such damage.

The severe weather pattern was created by Minnesota being in the main belt of steering winds with very warm and sticky air to the south and relatively cooler air to the north. Thunderstorms frequently developed on the cool side of this front as individual storm systems moved along this boundary.

June Temperatures Near Normal, but Highs Held Down

The persistent showers and thundersotrms kept skies partly to mostly cloudy in St. Cloud, helping to hold down high temperatures. The average June high temperature at the St. Cloud Regional Airport was 76.1°F, 1.2°F cooler than normal. However, June 2009 had an even colder average high of 74.8°F. There were only 9 days with a high of at least 80°F, while St. Cloud had 8 such days in May, including two days when the high broke 90°F. However, the persistent clouds and relatively high humidity kept the low temperatures up. The St. Cloud average June low temperature was 55.3°F, 2.4°F warmer than normal. The average for June was 65.7°F, 0.6°F above normal. Still, it was the warmest June since 2007. In fact, four of the past 7 Junes have been cooler.

Summer Weather At Least for A While to Start July

The weather pattern has temporarily shifted to a much warmer one for the first several days of July. High temperatures in the 80's, if not 90's, will be common well into the holiday weekend. Humidity will also be on the rise, leading to thunderstorms by Saturday night into Sunday.

    June 2010 Statistics