Strong winds on Sunday, June 10thBoth weekend days (June 9-10) brought temperatures in the 90s F to many areas, including 93 F at Milan and Crookston, and 94 F at Wheaton and Madison. Then, late afternoon and evening on Sunday, June 10th saw strong thunderstorms cross the state of Minnesota. A tornado was reported near Belle Plaine in Scott County (preliminary estimates are an EF-0 with winds of 65-85 mph) where some farm buildings were damaged, and there were at least 30 other reports of very strong winds, including 63 mph at Kabetogama Lake up north. Olivia reported winds to 59 mph and MSP airport recorded a wind of 52 mph, just around the time all of the tree damage was reported in the Highland Park neighborhood of St Paul. Many other communities reported winds over 40 mph. The cold front associated with the thunderstorms brought a rapid change in temperature, as the MSP airport reading fell from 87 degrees F to just 69 degrees F between 9:00 pm and 10:00 pm.
The rainfall was welcome in most areas. Some observers reported over 1 inch, including Belle Plaine, Princeton, Cambridge, St Peter, Little Falls, Rush City, and Plymouth. For many it was the first significant rainfall of the month.
Cold June 12th and 13th up northMany northern Minnesota observers reported low temperatures in the 30s F on Tuesday, June 12th and Wednesday, June 13th. On Tuesday morning St Vincent reported 38 degrees F, while Fosston measured 37 degrees F. Hallock reported 36 degrees F, and Warroad reported a record-tying 32 degrees F (tied with June 12, 1969). Then on Wednesday morning Brimson reported a near-record 34 degrees F, while Hibbing and Embarrass recorded 36 F and 37 F, respectively. Some SD and ND communities across Minnesota's western border reported record-setting low temperatures as well. Northeastern Minnesota communities like Ely and Grand Marais did not see daytime highs climb out of the 50s F on June 12th as a result of the cool Canadian high pressure system that dominated the state.
Heavy rain and hail on June 14thA low pressure system moving across southern Canada brought strong winds, hail, and heavy rains to many parts of Minnesota on Thursday, June 14th. There were numerous reports of hail from one half inch to one inch in diameter. Very strong winds brought down power lines along Hwy 2 in St Louis County. Some areas of central and eastern Minnesota received rainfalls from a half inch to over one inch during the morning and early afternoon. But the BIG STORY was the very heavy, record-setting rainfalls across Steele, Rice, Le Sueur, Dakota, and Goodhue Counties. Observers in these counties reported from 2 to 8 inches of rainfall during the afternoon and evening. Some record-setting amounts included 2.22 inches at Montgomery, 2.86 inches at Farmington, 6.37 inches at Red Wing Dam, and 8.83 inches at Cannon Falls. The rainfall at Cannon Falls was a new all-time statewide record for the month of June surpassing 8.67 inches at Minnesota on June 17, 1957. As a result of the heavy rainfalls the Cannon River and Little Cannon River rose several feet and exceeded flood state, causing road closures and evacuation of some homes. More information on the rainfall and flooding can be found at these links:
Weekly Weather PotpourriNOAA-National Weather Service in Mobile, AL reported some tremendous rainfalls last weekend (June 9-10) across coastal Alabama and the Florida Panhandle. Some of the rainfall totals included: Pensacola, FL 15.05 inches; Orange Beach, AL 11.32 inches; Mobile, AL 12.90 inches; Brentwood, FL 14.57 inches; and Myrtle Grove, FL 17.50 inches. Many city streets were flooded.
NOAA-National Hurricane Center was monitoring Hurricane Carlotta in the Eastern Pacific off the southern coast of Mexico. It was producing sustained winds of 80 mph with gusts to 90 mph, and sea waves of 25 feet. Carlotta was expected to strengthen before making landfall in Mexico over the weekend. It may bring rainfalls of 6 to 10 inches to some areas.
Typhoon Guchol was intensifying off the east coast of the Philippines in the Western Pacific Ocean. It was producing sea waves near 35 feet and winds up to 115 mph. Fortunately it is expected to remain out to sea as it grows stronger over the weekend and heads north towards Kyoto and the south coast of Japan.
Dr. Robert Simpson, former Director of NOAA's National Hurricane Center, and originator of the Saffir-Simpson scale used in hurricane forecasting will turn 100 years old later this year. Retired in Washington, D.C. he was interviewed for a recent article in USA Today. You can find the article here.
MPR listener questionWhat causes thunderstorms to dissipate rapidly?
Answer: Since mature thunderstorms are fed by warm, moist air rising within the clouds the rainfall itself and the down drafts of the storm pulling cooler air to the surface tend to cause the dissipation of the storm. Also these storms may be impeded by wind shear aloft which does not allow the vertical motion to create high cloud tops. In addition animated satellite and radar imagery show that storms encountering an extremely dry or cold landscape may weaken rapidly and die off. This can certainly happen over the relatively cool waters of Lake Superior in the summer.
Twin Cities Almanac for June 15thThe average MSP high temperature for this date is 78 degrees F (plus or minus 7 degrees F standard deviation), while the average low is 59 degrees F (plus or minus 7 degrees F standard deviation).
MSP Local Records for June 15thMSP weather records for this date include: highest daily maximum temperature of 94 degrees F in 1913; lowest daily maximum temperature of 61 degrees F in 1945; lowest daily minimum temperature of 41 F in 1989; highest daily minimum temperature of 71 F in 2007; and record precipitation of 2.80 inches in 1874.
Average dew point for June 15th is 54 degrees F, with a maximum of 73 degrees F in 1952 and a minimum of 32 degrees F in 1961.
All-time state records for June 15thThe state record high temperature for this date is 106 degrees F at Lamberton (Redwood County) in 1979. The state record low temperature for this date is 24 degrees F at Meadowlands (St Louis County) and at Roseau (Roseau County) in 1917. State record precipitation for this date is 7.50 inches at Albert Lea (Freeborn County) in 1978; and no snowfall has been reported on this date.
Past Weather Features:June 15, 1874 brought thunderstorms that produced 2.80 inches of rainfall in the Twin Cities, and a rapid rise in the Mississippi River. That was the wettest June ever for the Twin Cities Metro Area. The month saw rainfall on 18 different days, and on four of those days it rained over 1 inch. June 1874 brought a total of 11.67 inches of rainfall, nearly a third of the entire year's precipitation for the Twin Cities Metro Area. Further north at Ft Ripley they received 9.30 inches of June rainfall, also a record.
June 15, 1892 also brought heavy thunderstorms to southern Minnesota communities. St Charles reported 2.69 inches, Blooming Prairie 4.50 inches, Sheldon 4.52 inches, and Grand Meadow reported 5.00 inches. Many fields were flooded and roads washed out.
June 15-19, 1913 brought a five day Heat Wave to Minnesota, with over 40 communities recording daytime highs in the 90s F. On June 15th it was 93 degrees F as far north as Two Harbors, still a record for the date there. At Farmington the mercury reached 100 degrees F. Other June Heat Waves occurred over June 15-19, 1933, and June 13-15, 1979, when many counties reported temperatures in the 90s F and some saw consecutive days with afternoon highs over 100 degrees F.
June 15, 1917 brought a hard freeze to some northern Minnesota communities. Meadowlands and Roseau reported morning lows of just 24 degrees F, while Pokegama Dam, Duluth, and Beardsley reported 28 degrees F. Light frost was observed as far south as Zumbrota.
June 14-15, 1978 brought heavy thunderstorms to parts of Freeborn, Faribault, and Blue Earth Counties in southern Minnesota. Rainfalls of 3 to 7 inches produced flash flooding and many road closures due to high water. Numerous basements were flooded in Albert Lea. Some of the rainfall amounts included 7.50 inches at Albert Lea, 5.50 inches at Blue Earth, and 3.51 inches at Winnebago.
On June 16, 1992 a total of 27 tornadoes were reported across Minnesota, including the last F-5 (winds 261 mph or greater) ever reported in the state. This F-5 tornado traveled from Leota to Chandler between 5:00 and 5:30 pm that afternoon, on the ground for 16 miles and at times a quarter of a mile in diameter. About the same time an F-4 tornado (winds 207-260 mph) was traveling through Lake Wilson, also in Murray County. These two tornadoes caused over $14 million in damages. Of the 25 other tornadoes reported that day, 6 were F-3 (158-206 mph), 15 were F-2 (113-157 mph), and 4 were F-1 (72-112 mph). Overall 20 counties reported tornado damage or damage from severe thunderstorm winds, totaling over $80 million.