The April 30, 1967 Tornadoes in Southern Minnesota: a Retrospective
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The April 30, 1967 Tornadoes in Southern Minnesota: A Retrospective National Weather Service, Chanhassen, Minnesota Originally written in 2007; updated in 2017 1 Table of Contents Section: Page: Introduction 3 The Weather Pattern 7 U.S. Weather Bureau Timeline 17 Damage Photos 25 Personal Accounts and Photos 37 Newspaper Accounts 68 The Aftermath 76 Times Have Changed 79 Acknowledgements 83 Cover photo by Duane O’Malley, U.S. Weather Bureau, Minneapolis Photographed in Waseca, Minnesota Radar image from April 30, 1967 from the U.S. Weather Bureau WSR-57, which was located at the Minneapolis-St Paul (MSP) International Airport. The MSP airport is at the center of the image. Brighter range rings are at intervals of 50 nautical miles; the radius is 250 nautical miles. 2 1. Introduction For long time residents of southern Minnesota, Sunday, April 30, 1967, known as “Black Sunday,” is a day that has lived in vivid detail for 50 years and will likely continue to be remembered for many years to come through stories passed through generations of Minnesotans. On Black Sunday, a windy, humid afternoon was replaced by an evening of devastation and destruction, as a series of northward moving supercell thunderstorms spawned several long tracked, violent tornadoes across Freeborn, Waseca, and Steele counties. Between the hours of 6 and 7 pm, portions of the cities of Albert Lea and Waseca were destroyed, while Owatonna barely escaped ruin from a tornado that passed just a mile west of the city limits. Mother Nature also took aim at more rural areas surrounding the communities of Alden, Hartland, New Richland, Myrtle, Clarks Grove, Ellendale, Emmons, and Twin Lakes. The amount of human suffering resulting from the Black Sunday tornadoes was tremendous. Thirteen Minnesotans perished, and eighty more were injured. The names of those lost in these storms follow. Mr. and Mrs. Elmer Manuel Herman Nehring Mrs. Michael Hassing Harlan Holleschau Mr. and Mrs. Merton Bickford Mr. and Mrs. John Ripple Mr. and Mrs. George Willock Mr. and Mrs. Art Rux 3 At the end of the day, nine tornadoes had affected south central and southeast Minnesota, including the seven in Freeborn, Waseca, and Steele counties and one each in Mower and Olmsted counties. Additional tornadoes occurred in northern and eastern Iowa. Of the nine Minnesota tornadoes, only one received a Fujita scale rating of less than F2 intensity. In all, southern Minnesota was raked by three F4s, two F3s, three F2s, and one F1. The maximum tornado width observed was 500 yards, almost a third of a mile, while the tornado that damaged Albert Lea and narrowly missed Owatonna traveled 40 miles without once lifting. Characteristics of each tornado affecting southern Minnesota, as outlined in Significant Tornadoes: 1680-1991 by Thomas P. Grazulis, are found on the next page. Property losses totaled 9 million dollars (not adjusted for inflation), including extensive agricultural and livestock losses. While Black Sunday certainly served as the “worst of times” for many in southern Minnesota, the tragedies of that evening also revealed the lend-a- hand spirit of local residents. Newspapers and other publications contained numerous accounts of communities banding together to resurrect their cities and take care of their own, as well as students and other volunteers traveling from many miles away to help those in need. This spirit certainly provided the lone silver lining to an otherwise tremendous catastrophe. 4 Fujita Path Path Narrative Description from Time Counties Rating Width Length Grazulis “Moved NNW from NW of Alden to Freeborn, 100 near Matawan. Farm damage was 6:05 F3 14 miles Waseca yards near-F4 in the first part of the path. Homes and barns were destroyed.” 6:05 Steele F1 Unknown Unknown “Moved N from near Hartland to 7 [miles] NNE of Waseca. This tornado followed Hwy-67 into Waseca, destroying or damaging farm buildings Freeborn, 500 6:15 F4 30 miles on both sides of the road. It cut a Waseca yards four-block-wide swath in town, destroying 16 homes, six of which were leveled, and 25 more were heavily damaged.” “Moved N, parallel to and 4 [miles] E of the previous tornado. Destroyed Freeborn, 6:15 F2 Unknown 30 miles barns were noted west of Lemond and Waseca Meriden. Little attention was paid to this event in the press.” “Moved N from 2 [miles] SE of Manly, Iowa to near Myrtle, Minnesota. This Freeborn, 400 tornado destroyed about 10 farms, 6:20 Worth F4 18 miles yards leveling at least three of them in near- (IA) F5 fashion. Ten other farms, mostly in Iowa, were extensively damaged.” “Moved NNE from SW of Twin Lakes to Albert Lea, Clarks Grove, Ellendale, Hope, and west of Owatonna. Farms were leveled at a half dozen locations Freeborn, 200 6:23 F4 40 miles along the path. There was $2,000,000 Steele yards damage in Albert Lea, where 26 homes were destroyed and 64 were badly damaged. Two deaths occurred near Owatonna.” “Moved N from just south of the Iowa Freeborn, border to near London. About a half 400 6:28 Worth F3 6 miles dozen farms were extensively yards (IA) damaged, with at least two farm homes destroyed.” “Moved N after touching down on a farm 1.5 [miles] SE of Austin. At least 7:15 Mower F2 Unknown 6 miles two barns and one home were unroofed and torn apart.” “Moved NE, from near Marion to NE of 8:10 Olmsted F2 Unknown 8 miles Eyota. A trailer and a barn were destroyed.” 5 Images showing the tornado tracks and locations of large hail reports 6 2. The Weather Pattern A dynamic and powerful combination of weather features converged on Minnesota and Iowa during the afternoon and evening hours of April 30, 1967, producing the severe weather and tornadoes across the area. The storm system wreaked havoc across a large section of the country over a two to three day period, including blizzard conditions in the Northern High Plains and Northern Rockies and severe thunderstorms and tornadoes in Texas, Oklahoma, Kansas, and the Mississippi and Ohio Valley regions. The Morning of April 30, 1967 The main branch of the upper level jet stream stretched from the southwestern United States into west Texas, snaking northeastward into the Central Plains and eastward through the Ohio Valley. A 135 knot speed maximum in the jet stream had nosed to near the eastern New Mexico and western Texas Panhandle border. In severe thunderstorm forecasting, the orientation and speed of the jet stream is important in producing large deep layer wind shear values, maintaining and organizes thunderstorm updrafts. In the mid levels, a closed low pressure area, oriented from northwest to southeast, was positioned from eastern Idaho, across Wyoming, and into north central Colorado. The diverging winds to the east of the low in the Plains states resulted in a large area of synoptic scale lift, which is a key ingredient in forecasting active weather during all seasons, including thunderstorms, flash floods, and winter storms. Just above the surface, a southwest to northeast oriented 50 knot speed maximum, known as the low level jet, stretched from central Oklahoma and into northeastern Missouri. The low level jet was responsible for transporting a large plume of moisture from the Gulf of Mexico into the Upper Midwest. A large supply of moisture is another critical element in thunderstorm forecasting, as it is necessary to form clouds and also increases the amount of environmental instability, which is necessary for air to accelerate upward to form and sustain a thunderstorm updraft. The low level jet also accentuates both the deep layer wind shear and the low level wind shear, the latter of which is critical to tornadic thunderstorm organization. At the surface, a stationary front, associated with a surface low pressure center near the central South Dakota and Nebraska border, stretched through the southern half of Minnesota, just south of the Twin Cities. Warm and moist air was found to the south of the stationary front, across southern Minnesota and points south. 7 850 millibar map, 7 a.m. CDT, April 30, 1967 700 millibar map, 7 a.m. CDT, April 30, 1967 8 500 millibar map, 7 a.m. CDT, April 30, 1967 300 millibar map, 7 a.m. CDT April 30, 1967 9 Midday April 30, 1967 At 1 pm CDT, the surface low pressure center had moved slightly northward to a position just southwest of Pierre, South Dakota. Several fronts stretched from the low pressure area, including the stationary front, located from north of Sioux Falls, South Dakota to near La Crosse, Wisconsin. A warm front also extended from south of Sioux Falls to near Des Moines, Iowa and St. Louis, Missouri. The air between the two fronts had warmed into the 60s and low 70s, and dew points in the 60s were prevalent. Winds across far northern Iowa and southern Minnesota were quite strong, with speeds in the 15 to 25 mph range, and from the east-southeast. 10 By 4 pm CDT, the only element of the surface pattern that had changed substantially was the location of the warm front. The front had bulged to just south of the Minnesota and Iowa border, extending from Worthington to near Mason City, Iowa. The stationary front remained in its previous location. The positions of both the warm front and the stationary front are noted, as the tornadoes developed along and just north of the warm front as it moved northward through northern Iowa and into southern Minnesota, and the stationary front marked the northward extent of the tornadic weather. Between the two fronts, temperatures were in the low to mid 70s, and dew points remained in the mid and upper 60s.