The atmosphere became very unstable Saturday afternoon, and along with a strong wind shear, aided in the development of very large hail, isolated tornadoes and significant straight-line wind damage. The first storm developed near Alexandria and moved southeast along Interstate 94 before dying in the southwest part of the Twin Cities late that afternoon.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MPX wrote it up.
The atmosphere became very unstable Saturday afternoon, and along with a strong wind shear, aided in the development of very large hail, isolated tornadoes and significant straight-line wind damage.
The first storm developed near Alexandria and moved southeast along Interstate 94 before dying in the southwest part of the Twin Cities late that afternoon. Numerous reports of very large hail, up to the size of softballs, occurred near St. Cloud, southeast to Watertown.
The next area of severe storms developed across central Minnesota, and far west-central Minnesota and moved east and southeast toward east-central Minnesota where a strong bow echo developed and moved across the northern portion of the Twin Cities Metropolitan Area.
There was widespread damage along the leading edge of this bow echo where numerous trees, power lines and homes were either uprooted, blown down, or destroyed.
These storms moved into west-central Wisconsin and also caused damage to trees before weakening toward the late evening.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Twin Cities, MN wrote its last area forecast discussion before the first event at Jul 17, 12:35 PM CST, 27 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 135 PM CDT SAT JUL 17 2010 .DISCUSSION... THE MAIN FORECAST CHALLENGE IS THE SEVERE WEATHER OCCURRING OVER THE AREA THIS AFTERNOON INTO THIS EVENING. AIRMASS WAS VERY PRIMED FOR THE DEVELOPMENT OF SUPERCELL ACROSS MUCH OF FORECAST AREA. THIS THE MAIN FOCUS WILL BE OVER WESTERN INTO SOUTH CENTRAL MINNESOTA. WEAK CAP OVER SOUTHWEST MN...EXPECTED TO ERODE BY LATE AFTERNOON OR EARLY THIS EVENING. THUNDERSTORMS CONTINUE TO FIRE ALONG AND NORTH OF WARM FRONT BOUNDARY OVER CENTRAL MN. MOST OF THE THUNDERSTORMS HAVE BEEN ELEVATED...SO THE MAIN THREATS OVER OUR AREA THIS AFTERNOON WILL BE LARGE HAIL AND DAMAGING WINDS. ONCE THE CAP ERODE NEAR THE WARM SECTOR SOUTH INTERSTATE 94...EXPECT SOME ISOLATED TORNADOES TO DEVELOP. THUNDERSTORM ACTIVITY IS EXPECTED TO DEVELOP INTO A MESOSCALE CONVECTIVE SYSTEM OVER SOUTHERN MN...WITH MOVES THE BULK OF THE SEVERE WEATHER BY 10 PM SOUTH OF OUR CWA. LATER TONIGHT...MORE OF HEAVY RAIN THREAT AS A SERIES OF SHORT WAVES MOVE ACROSS THE AREA OVERNIGHT. MOST OF THE SHOWERS AND THUNDERSTORMS SHOULD BE OUT OF OUR FORECAST AREA BY MIDNIGHT...EXCEPT OVER PARTS OF WEST CENTRAL WI AND EXTREME SOUTH CENTRAL MN. HYDROLOGICAL CONCERNS...THUNDERSTORMS ARE EXPECTED TO TRAIN OVER PARTS OF WEST CENTRAL INTO SOUTH CENTRAL MN TONIGHT. SEVERAL WEAK SHORTWAVE TROUGHS MOVING OVER THE UPPER MIDWEST TONIGHT...EXPECT A BACKWARD PROPAGATING MESOSCALE CONVECTIVE COMPLEX TO DEVELOPS OVER WESTERN MN LATER THIS EVENING. PRECIP WATER VALUES OF 2.00 TO 2.50 INCHES ARE FORECAST OVER THIS AREA. EVEN WITH FORECAST QPF 3.00 OR 4.00 INCHES. IT SHOULD NOT BE A PROBLEM ON THE MAIN STEMS OF THE RIVERS TONIGHT. NEXT CHANCE OF THUNDERSTORMS IS MONDAY AS ANOTHER WEAK SHORT WAVE TROUGH. LONG RANGE FORECAST...MODELS DIFFER ON THE THREAT OF PRECIPITATION FOR THE UPPER MIDWEST THROUGH END OF THE WORK WEEK. GFS MODEL KEEPS MUCH OF THE FORECAST AREA DRY...WHILE THE PERSISTENT EUROPEAN MODEL KEEPS US WET THROUGH FRIDAY. WL LEAN MORE TOWARDS THE EUROPEAN MODEL...AS SEVERAL MINOR IMPULSES RIDE OVER THE UPPER RIDGE OVER THE UPPER MIDWEST. TIMING OF THE INITIATION OF THUNDERSTORMS WILL BE CRITICAL. && .AVIATION.../18Z TAF ISSUANCE/ MAIN CONCERN IS THUNDERSTORM DEVELOPMENT...COVERAGE AND SEVERITY AND THE IMPACT ON THE TAF SITES. CONVECTION BEGINNING IN WESTERN MN AND NORTH CENTRAL MN. THUNDERSTORMS HAVE A SOUTHEAST MOVEMENT AT 35 KTS AND ARE WIDELY SCATTERED IN WRN MN...WHERE AS WE HAVE A LARGER AREA OF SHOWERS AND THUNDERSTORMS IN NORTH CENTRAL MN. EXPECT THE CONVECTION IN WESTERN MN TO REMAIN WIDELY SCATTERED THOUGH 20Z BEFORE BECOMING ORGANIZED INTO A LARGER COMPLEX ASSOCIATED WITH STRONG WINDS AND LARGE HAIL. AN ISOLATED TORNADO IS POSSIBLE AS WELL. DO NOT EXPECT THE COMPLEX IN NORTH CENTRAL MN TO GET MUCH STRONGER OR WIDESPREAD AS THE MOST UNSTABLE CONDITIONS ARE EXPECTED AFTER 21Z AND CONTINUING THROUGH 04Z. AFT 21Z WE EXPECT THE WIDELY SCATTERED SHOWERS AND THUNDERSTORMS IN FAR WESTERN MN DEVELOP FURTHER AND ORGANIZE INTO A LARGE COMPLEX AND MOVE SOUTHEAST. IT IS LIKELY THAT MOST /IF NOT ALL/ TAF SITES WILL EXPERIENCE THUNDERSTORM ACTIVITY AT SOME POINT BETWEEN 21Z SATURDAY AND 06Z SUNDAY. KMSP...A FEW MID CLOUDS FOR EARLY THIS AFTERNOON AS SHOWER AND THUNDERSTORM ACTIVITY APPROACH THE METRO AREA. DO NOT EXPECT TO SEE THUNDERSTORM ACTIVITY UNTIL 22Z. NON THUNDERSTORM WIND GUSTS AS HIGH AS 20 KTS ARE POSSIBLE LATER THIS AFTERNOON AS THE TROUGH APPROACHES. EXPECT THE MAIN THUNDERSTORM ACTIVITY BETWEEN 21Z AND 03Z SUNDAY AND CONDITIONS MAY BECOME IFR AFTER 00Z AND CONTINUE THROUGH 4Z DEPENDING ON THE TRACK AND INTENSITY OF THE THUNDERSTORM COMPLEX WE EXPECT TO MOVE SOUTHEAST. WIND GUSTS MAY BE TOO LIGHT IN THE TAF BETWEEN 00 AND 04Z AND WILL HAVE TO WATCH THAT CLOSELY. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && JM/DL
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1144 AM CDT SAT JUL 17 2010 MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028- 180915- DOUGLAS-TODD-MORRISON-MILLE LACS-KANABEC-STEVENS-POPE-STEARNS- BENTON-SHERBURNE-ISANTI-CHISAGO-LAC QUI PARLE-SWIFT-CHIPPEWA- KANDIYOHI-MEEKER-WRIGHT-HENNEPIN-ANOKA-RAMSEY-WASHINGTON- YELLOW MEDICINE-RENVILLE-MCLEOD-SIBLEY-CARVER-SCOTT-DAKOTA- REDWOOD-BROWN-NICOLLET-LE SUEUR-RICE-GOODHUE-WATONWAN-BLUE EARTH- WASECA-STEELE-MARTIN-FARIBAULT-FREEBORN-POLK-BARRON-RUSK- ST. CROIX-PIERCE-DUNN-PEPIN-EAU CLAIRE- 1144 AM CDT SAT JUL 17 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL AND SOUTHERN MINNESOTA...AND WEST CENTRAL WISCONSIN. .DAY ONE...THIS AFTERNOON AND TONIGHT THE ENTIRE AREA REMAINS UNDER A MODERATE RISK OF SEVERE THUNDERSTORMS. THUNDERSTORMS ARE EXPECTED TO DEVELOP IN WEST CENTRAL AND CENTRAL MINNESOTA THIS AFTERNOON...WITH SOME OF THESE STORMS LIKELY BECOMING SEVERE. THUNDERSTORMS ARE EXPECTED TO BECOME MORE WIDESPREAD ACROSS THE AREA THIS EVENING. INITIALLY THE PRIMARY THREAT WILL BE LARGE HAIL WITH A FEW TORNADOES POSSIBLE. DURING THE EVENING AND INTO THE OVERNIGHT THE PRIMARY THREAT WILL BECOME DAMAGING WINDS AND HEAVY RAINFALL. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THE WEEK AHEAD LOOKS LIKE A CONTINUATION OF AN ACTIVE WEATHER PATTERN WITH THUNDERSTORMS ALREADY RETURNING BY MONDAY. .SPOTTER INFORMATION STATEMENT... SKYWARN SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND INTO TONIGHT.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1215 PM CDT SAT JUL 17 2010
MNZ047>049-055>057-171815-
CHIPPEWA-KANDIYOHI-POPE-STEARNS-STEVENS-SWIFT-
1215 PM CDT SAT JUL 17 2010
AT 1213 PM CDT...WEATHER SERVICE RADAR WAS TRACKING A STRONG
THUNDERSTORM NORTH OF ORTONVILLE...OR 6 MILES SOUTHWEST OF CHOKIO.
THIS STORM WAS MOVING EAST AT 30 MPH.
PEA SIZE HAIL AND WINDS UP TO 40 MPH ARE EXPECTED WITH THIS STORM.
* LOCATIONS IN OR NEAR THE PATH OF THIS STORM INCLUDE...
CHOKIO.
ALBERTA.
HANCOCK.
CLONTARF.
BENSON.
LAT...LON 4537 9488 4494 9495 4536 9614 4540 9614
4541 9624 4562 9627
TIME...MOT...LOC 1714Z 285DEG 28KT 4553 9628SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
108 PM CDT SAT JUL 17 2010
MNZ047-055-056-171900-
CHIPPEWA-STEVENS-SWIFT-
108 PM CDT SAT JUL 17 2010
AT 106 PM CDT...WEATHER SERVICE RADAR WAS TRACKING A STRONG
THUNDERSTORM 7 MILES EAST OF ARTICHOKE. THIS STORM WAS MOVING
SOUTHEAST AT 25 MPH.
HAIL UP TO NICKEL SIZE AND WINDS UP TO 50 MPH ARE EXPECTED WITH THIS
STORM.
* LOCATIONS IN OR NEAR THE PATH OF THIS STORM INCLUDE...
DANVERS.
BENSON.
DE GRAFF.
LAT...LON 4555 9608 4548 9574 4541 9574 4541 9546
4539 9531 4509 9556 4536 9614 4540 9614
4540 9619
TIME...MOT...LOC 1808Z 299DEG 23KT 4541 9600SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 116 PM CDT SAT JUL 17 2010 MNZ041>043-049-171900- DOUGLAS-MORRISON-STEARNS-TODD- 116 PM CDT SAT JUL 17 2010 AT 112 PM CDT...WEATHER SERVICE RADAR WAS TRACKING A STRONG THUNDERSTORM 3 MILES WEST OF CLOTHO. THIS STORM WAS MOVING SOUTHEAST AT 25 MPH. ONE HALF INCH DIAMETER HAIL AND WINDS UP TO 40 MPH ARE EXPECTED WITH THIS STORM. * LOCATIONS IN OR NEAR THE PATH OF THIS STORM INCLUDE... CLOTHO. BROWERVILLE. LONG PRAIRIE. BURTRUM. LAT...LON 4611 9437 4562 9472 4596 9524 4612 9513 TIME...MOT...LOC 1816Z 295DEG 22KT 4600 9507
The Minneapolis radar (KMPX), 167 km away, was scanning. The volume nearest the first event began at 19:03 UTC.
36 thunderstorm wind, 17 hail, 9 heavy rain, 4 tornado, 1 funnel cloud. Local standard time, as filed.
Many crops were damaged, with corn shredded.
Several large trees were blown down east of Lake Osakis.
Several large tree branches were blown down along County Road 17, east of Sauk Centre, Minnesota. In addition, a trained spotter measured a 54 knot wind gust from his personal anemometer.
Several trained spotters reported numerous golf ball, to baseball size hail from near St. Martin, east-southeast to near Richmond, Minnesota. Several areas had car windshields broken.
Several trained spotters reported numerous golf ball, up to soft ball size hail between Cold Spring and St. Nicholas.
Several trained spotters reported numerous nickel, up to baseball size hail stones near Kimball, Minnesota.
Several trained spotters reported numerous nickel, up to baseball size hail from near South Haven, south-southeast to near French Lake, Minnesota.
About one dozen trees were toppled due to a downburst. One tree fell on a house.
Several trained spotters reported numerous nickel, up to hen egg size hail from southwest of Annandale, to northeast of Cokato.
Several trained spotters reported numerous dime, up to hen egg size hail from north of Howard Lake, southeast to north of Montrose, Minnesota.
Several trained spotters reported numerous dime, up to baseball size hail from north of Watertown, southeast to the southeast part of Watertown. Damage was extensive to crops and homes throughout the area.
Several trained spotters reported numerous dime, up to baseball size hail from west of Minnetrista, southeast to Minnetrista, St. Bonifacius and Mound.
Dozens of trees were toppled in and around Staples, with some trees landing on vehicles, sheds and houses. The roof of a hardware store was partially removed.
Scattered trees and a few power lines were reported down.
Trained spotters reported numerous quarters, up to golf ball size hail from northwest of Little Falls, to east of Little Falls.
A trained spotter measured an 81 mph wind gust near Highway 25 and 63rd Street. This was associated with the rear flank downdraft accompanying the Buckman tornado.
Several dozen trees were downed, two sheds and a barn were damaged, and minor damage occurred to a house.
Power lines were reported blown down near Pennock, Minnesota.
Several dozen trees were toppled. The roof was partially removed from a barn, and a couple of sheds also sustained damage from a downburst.
About one dozen trees, and some large branches, were broken or toppled. Minor damage to several houses was noted.
Hundreds of trees were snapped or uprooted, roofs removed from sheds, and several outbuildings destroyed. A house sustained minor damage, with the roof partially removed above a porch, and some shingles and siding removed.
Several large 13-15 inch diameter trees were uprooted near Becker, Minnesota. In addition, a farm irrigation system was destroyed.
A trained spotter measured a wind gust of 70 mph.
A trained spotter reported six inch diameter trees blown down.
Numerous trees were blown down, along with damage to a farm's fence. Extensive damage occurred in the town of Elk River Minnesota, including the Sherburne County Fair where tents and sheds were blown over.
Numerous 1-2 foot diameter trees were blown down.
Several trees were blown down east of Elk River, Minnesota.
Numerous large trees fell in a large swath from southeast Hassan Township to the southeast part of Dayton, and to Champlin, Minnesota. There was a report of a funnel cloud in the area, but none of the damage appeared tornadic. A damage survey revealed downburst damage in the area.
A railroad gate crossing was damaged on Main Street, east of Anoka, Minnesota.
Several eight inch diameter trees were snapped off on Viking Blvd near Oak Grove, Minnesota.
Several 12-16 inch diameter Maple Trees were snapped in half near Cedar, Minnesota.
The Crystal Airport measured a 50 knot wind gust. In addition, several large tree limbs were blown down around Brooklyn Center, Minnesota.
A 20-24 inch diameter tree was blown down near the intersection of Highway 242 and Highway 65, northeast of Blaine, Minnesota. In addition, several 18-24 inch diameter trees were blown down at the Blaine City Hall on Radisson Road.
Numerous large tree limbs were blown down from Mounds View, to New Brighton, Shoreview, Arden Hills and Vadnais Heights, Minnesota, including three large trees that fell on a home in Arden Hills and damaged it. A trained spotter measured a wind gust of 70 mph in Vadnais Heights.
Several 6-7 inch diameter trees were blown down in Ham Lake, Minnesota.
Several six inch diameter tree branches were blown down near Lino Lakes, Minnesota.
A few 8-12 inch diameter trees were blown down near East Bethel, Minnesota.
Tree limbs were snapped in half near Hennepin Avenue, and Hwy 280.
Several 6-12 inch diameter trees were blown down along Highway 61 in White Bear Lake, Minnesota.
Several trees were uprooted in North St. Paul, Minnesota.
Hundreds of trees were broken or toppled, including some that fell on sheds and houses. Shingles and soffits were removed from some houses.
Measured at St Paul's Holman Field (STP).
Several 2-3 inch diameter tree limbs were blown off near Withrow, Minnesota.
Several six inch diameter trees were blown down north of Stillwater, Minnesota.
Several large trees were blown over in William O Brien State Park. One large tree fell on a camper and destroyed it.
A few dozen trees were felled from rear flank downdraft winds in the wake of the dissipation of the Forest Lake tornado.
A trained spotter measured 2.01 inches of rain in 30 minutes, with a total of 3.02 inches in three hours.
A Minnesota Department of Transportation wind sensor measured a wind gust of 51 knots.
A large tree was uprooted near Amboy, Minnesota.
A total of 3.25 inches of rain fell in six hours.
An observer measured 2.95 inches of rainfall in six hours.
An observer measured 2.00 inches of rainfall in six hours.
An observer measured 2.68 inches of rainfall in six hours.
An observer measured 2.66 inches of rainfall in six hours.
An observer measured 3.25 inches of rainfall in three hours.
An observer measured 2.5 inches of rain in three hours.
An observer measured 3.00 inches of rainfall in three hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2010Every state in 2010This day in weather historyThe tornado archive for Minnesota, 2010Warnings in Minnesota, July 2010
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 234072, 248983, 234076, 234164, 234091, 234165, 234092, 234093, 234097, 234105, 234107, 254573, 247514, 234111, 234114, 234123, 234119, 234133, 234202, 234129, 247510, 234132, 234213, 234135, 234214, 247502, 234235, 247505, 247512, 247513, 235470, 234238, 234239, 234257, 234262, 254571, 235418, 247516, 235478, 235445, and more.