Two lines of severe thunderstorms moved across western Wisconsin during the afternoon and evening of May 17th. This was the third day in a row that severe weather impacted the area.
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 ARX wrote it up.
Two lines of severe thunderstorms moved across western Wisconsin during the afternoon and evening of May 17th. This was the third day in a row that severe weather impacted the area. The storms primarily produced damaging winds, but also dropped one tornado. An EF-1 tornado moved across southern Trempealeau County east of Galesville and damaged farm buildings and trees. Trees were blown down on houses and cars in Strum (Trempealeau County), winds were measured at 80 mph in Patch Grove (Grant County) with numerous barns and outbuildings destroyed.
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 La Crosse, WI wrote its last area forecast discussion before the first event at May 17, 12:41 PM CST, 1 hour 24 minutes earlier.
Area Forecast Discussion National Weather Service La Crosse WI 141 PM CDT Wed May 17 2017 .SHORT TERM...(Tonight through Thursday Night) Issued at 141 PM CDT Wed May 17 2017 Main focus is on severe potential this afternoon into this evening. Current analysis has surface/mid-level low pressure center over eastern Nebraska. Radar has some ongoing showers/thunderstorms ahead of the low moving across portions of southwest into central WI. Otherwise, temperatures were in the upper 60s to middle 70s with dew points in the 60s. Severe threat looks on track for the area this afternoon into this evening as the low lifts out of Nebraska into southeast MN. Increasing MuCape/Bulk Shear/Helicity sets up across our area for the likelihood of supercell thunderstorms capable of large hail, damaging winds and a few tornadoes. The highest tornado threat looks to be from northeast IA into southwest in central WI. The highest severe threat time still looks to be in the 3 to 8 pm time frame. There will also be the likelihood of some localized heavier rainfall from the storms with precipitable water values around 1.5 inches. Look for these storms to exit the area by later this evening but lingering showers will continue through the night into Thursday on the backside of the departing low/cyclonic flow aloft. Otherwise, cooler temperatures will be seen Thursday under clouds and cold cyclonic flow aloft. Look for highs only in the 50s to middle 60s along with brisk north winds. Decreasing cloudiness is expected Thursday night mainly north of I- 90 as high pressure noses in from Canada. Low temperatures are expected to dip into the middle 30s to lower 40s. .LONG TERM...(Friday through Wednesday) Issued at 141 PM CDT Wed May 17 2017 Friday will see a chance of showers mainly southwest of I-94 as a mid-level trough and push of 850mb moisture transport move in. Otherwise, still on the cool side with highs only in the 50s. Low pressure lifts from the Southern Plains into the region Friday night through Saturday for the likelihood of showers and isolated thunderstorms. Otherwise, gulf looks wide open with this system for plenty of available moisture. Look for the bulks of showers to move out by late Saturday night, with a lingering chance of showers on Sunday across north central WI. Otherwise, temperatures stay below normal with highs Saturday and Sunday in the upper 50s to the middle 60s. Cooler cyclonic flow aloft lingers over the region Monday through Wednesday for shower chances and temperatures remaining below normal. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) Issued at 1238 PM CDT Wed May 17 2017 Main taf concerns are thunderstorms at both RST/LSE taf sites this afternoon into this evening...then the potential for IFR/MVFR conditions after 06z Thursday. Low pressure pushing into western Iowa is expected to spread a couple of rounds of showers/thunderstorms into the area this afternoon into this evening. Large hail and damaging winds are possible with the thunderstorms at both taf sites late this afternoon into this evening. Timing/placement of each individual band of showers/thunderstorms moving into the taf sites will be tricky. At this time...have introduced vicinity thunderstorms through this evening at both RST/LSE taf sites...with a tempo group late this afternoon into early evening hours to cover the timing of one of the convective bands. Showers will continue after 06z Thursday...however ceilings will lower into the IFR/MVFR conditions at both RST/LSE taf sites. && .HYDROLOGY...(This afternoon into Tonight) Issued at 141 PM CDT Wed May 17 2017 As of late this morning, emergency management and local law enforcement reported numerous county and township roads closed due to water over roads and washed out roadways across northern Trempealeau, northwest Jackson and northeast Buffalo counties. These were areas where radar estimated 4-6 inches had fallen last night. As a result, Areal Flood Warnings remain in effect for portions of northeastern Buffalo and northern Trempealeau/Jackson counties until midnight tonight. In addition, river flood warnings are also in effect for the Black River and Trempealeau Rivers. More showers and thunderstorms are expected this afternoon into tonight across the forecast area with another 1/2 to locally 2 inches of rainfall possible. This will keep rivers running higher than usual and could produce some ponding of water on roadway and lower lying areas, but flash flooding is not anticipated due to the expected fast-moving nature of the showers and storms, thereby not being focused over a certain area for any length of time. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && SHORT TERM...DAS LONG TERM....DAS AVIATION.....DTJ HYDROLOGY....DAS
Hazardous Weather Outlook National Weather Service La Crosse WI 952 AM CDT Wed May 17 2017 IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029- 032>034-041>044-053>055-061-181100- Mitchell-Howard-Winneshiek-Allamakee-Floyd-Chickasaw-Fayette- Clayton-Wabasha-Dodge-Olmsted-Winona-Mower-Fillmore-Houston- Taylor-Clark-Buffalo-Trempealeau-Jackson-La Crosse-Monroe-Juneau- Adams-Vernon-Crawford-Richland-Grant- 952 AM CDT Wed May 17 2017 This Hazardous Weather Outlook is for portions of southeast Minnesota, northeast Iowa, and southwest into central Wisconsin. .DAY ONE...Rest Of Today and Tonight Severe thunderstorms are expected this afternoon and evening, mainly between 3 pm and 8 pm. The risks will be isolated tornadoes, damaging winds and large hail. At this time, the tornado risk looks to be across northeast Iowa into western and central Wisconsin. Storms with damaging winds and large hail could occur across the entire area. Locally heavy rain will be possible with any storm, however, the storms should be fast moving limiting the potential for flash flooding. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Another round of widespread rain looks to spread across the area Friday into Saturday night, with amounts of 3/4 inch to locally 1 1/2 inches appearing likely. Isolated thunderstorms are also possible later Friday night and Saturday. Severe weather is not expected with any of these storms. .SPOTTER INFORMATION STATEMENT... Spotter groups should be prepared for activation from mid afternoon into the evening hours. Severe weather reports, including heavy rainfall and ongoing flooding, are appreciated through this evening. .EMERGENCY MANAGEMENT COORDINATION... A webinar has been scheduled for 1 pm. 04/DAS
Special Weather Statement
National Weather Service La Crosse WI
120 PM CDT WED MAY 17 2017
WIZ029-034-171845-
Jackson-Clark-
120 PM CDT WED MAY 17 2017
...A LINE OF STRONG THUNDERSTORMS WILL AFFECT CLARK AND CENTRAL
JACKSON COUNTIES...
At 119 PM CDT, radar indicated strong thunderstorms were located
along a line extending from near Humbird to Hatfield to Millston.
Movement was northeast at 65 mph.
Winds in excess of 40 mph and pea size hail are possible with these
storms.
These storms will be near...
Neillsville around 130 PM CDT.
Loyal and Shortville around 140 PM CDT.
Greenwood and Spencer around 145 PM CDT.
Other locations impacted by these storms include Sherwood, Colby,
Lynn, Merrillan and Willard.
LAT...LON 4494 9031 4440 9032 4416 9071 4416 9075
4433 9080 4442 9104 4501 9047
TIME...MOT...LOC 1819Z 206DEG 57KT 4446 9092 4442 9073 4422 9067
JSBSpecial Weather Statement
National Weather Service La Crosse WI
142 PM CDT WED MAY 17 2017
WIZ017-029-171945-
Taylor-Clark-
142 PM CDT WED MAY 17 2017
...A LINE OF THUNDERSTORMS WILL AFFECT CENTRAL CLARK AND EASTERN
TAYLOR COUNTIES...
At 140 PM CDT, radar indicated a line of thunderstorms extending
from 10 miles west of Greenwood to near Loyal to 9 miles east of
Shortville. Movement was northeast at 55 mph.
Winds up to 30 mph and pea size hail are possible with these storms.
These storms will be near...
Loyal around 145 PM CDT.
Owen, Colby and Abbotsford around 200 PM CDT.
Abbotsford around 205 PM CDT.
Dorchester and Dorchester around 210 PM CDT.
Medford around 215 PM CDT.
Rib Lake around 230 PM CDT.
Other locations impacted by these storms include Colby, Lynn,
Longwood, Stetsonville and Goodrich.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
LAT...LON 4512 9004 4512 9020 4503 9020 4503 9031
4442 9033 4466 9059 4474 9092 4479 9092
4538 9014 4538 9005
TIME...MOT...LOC 1840Z 226DEG 49KT 4478 9082 4471 9053 4452 9032
JSBSpecial Weather Statement
National Weather Service La Crosse WI
216 PM CDT WED MAY 17 2017
WIZ017-029-171945-
Taylor-Clark-
216 PM CDT WED MAY 17 2017
...A LINE OF STRONG THUNDERSTORMS WILL AFFECT NORTHERN CLARK AND
TAYLOR COUNTIES...
At 216 PM CDT, radar indicated strong thunderstorms were located
along a line extending from 12 miles south of Jump River to near
Medford to 12 miles east of Abbotsford. Movement was north at 65 mph.
Wind gusts up to 50 mph and pea size hail are possible with these
storms.
These storms will be near...
Chelsea around 220 PM CDT.
Rib Lake, Westboro and Jump River around 225 PM CDT.
Other locations impacted by these storms include Reseburg,
Stetsonville, Goodrich, Withee and Gilman.
LAT...LON 4526 9004 4512 9005 4512 9020 4503 9020
4503 9031 4498 9032 4489 9082 4507 9092
4538 9092 4538 9007
TIME...MOT...LOC 1916Z 185DEG 58KT 4518 9076 4518 9026 4496 9005
JSBSpecial Weather Statement
National Weather Service La Crosse WI
248 PM CDT WED MAY 17 2017
WIZ042>044-172015-
Juneau-Adams-Monroe-
248 PM CDT WED MAY 17 2017
...A STRONG THUNDERSTORM WILL AFFECT JUNEAU...ADAMS AND EAST CENTRAL
MONROE COUNTIES...
At 247 PM CDT, strong thunderstorms were located over Adams and
Juneau counties in central Wisconsin. The strongest thunderstorm was
located near New Lisbon, or 11 miles north of Mauston, moving
northeast at 45 mph.
Winds in excess of 40 mph and hail up to quarters are possible with
this storm.
This storm will be near...
Necedah and Dellwood around 255 PM CDT.
New Rome around 315 PM CDT.
Other locations impacted by this storm include Lemonweir, Strongs
Prairie, Big Flats, Lindina and Camp Douglas.
LAT...LON 4364 8992 4369 9031 4373 9031 4373 9033
4425 9031 4425 8960 4364 8960
TIME...MOT...LOC 1947Z 218DEG 40KT 4396 9017
JSBSpecial Weather Statement
National Weather Service La Crosse WI
250 PM CDT WED MAY 17 2017
IAZ008>010-018-019-029-MNZ079-086>088-094-095-172145-
Winneshiek-Floyd-Howard-Chickasaw-Fayette-Mitchell-Wabasha-Olmsted-
Dodge-Fillmore-Winona-Mower-
250 PM CDT WED MAY 17 2017
...SEVERE STORM THREAT INCREASING OVER NORTHEAST IOWA AND SOUTHEAST
MINNESOTA THIS AFTERNOON...
At 245 PM CDT, thunderstorms were developing rapidly across
northeast Iowa and southeast Minnesota. Through late afternoon,
these storms have the potential to become severe. The main risks
from the storms are...
large hail...damaging winds...and tornadoes.
Know your safety plan should a warning be issued for your area. Stay
weather aware this afternoon with multiple sources for your weather
information.
Law enforcement should prepare now for a busier period by later
afternoon with storm damage on the increase.
Prepare now for possible severe weather. Seek shelter when warnings
are issued. For tornado warnings, seek shelter below ground.
LAT...LON 4420 9304 4412 9218 4339 9166 4264 9161
4270 9208 4291 9208 4291 9303
TIME...MOT...LOC 1944Z 198DEG 44KT 4322 9238
DABSpecial Weather Statement
National Weather Service La Crosse WI
302 PM CDT WED MAY 17 2017
IAZ008>010-018-019-029-MNZ079-086>088-094-095-172145-
Winneshiek-Floyd-Howard-Chickasaw-Fayette-Mitchell-Wabasha-Olmsted-
Dodge-Fillmore-Winona-Mower-
302 PM CDT WED MAY 17 2017
...SEVERE STORM THREAT INCREASING OVER NORTHEAST IOWA AND SOUTHEAST
MINNESOTA THIS AFTERNOON...
At 300 PM CDT, thunderstorms were developing rapidly across
northeast Iowa and southeast Minnesota. Through late afternoon,
these storms have the potential to become severe. The main risks
from the strongest storms are...
large hail...damaging winds...and tornadoes.
Many storms will be capable of dime sized hail and wind gusts of 40-
50 mph.
Know your safety plan should a warning be issued for your area. Stay
weather aware this afternoon with multiple sources for your weather
information.
Law enforcement should prepare now for a busier period by later
afternoon with storm damage on the increase.
Prepare now for possible severe weather. Seek shelter when warnings
are issued. For tornado warnings, seek shelter below ground.
LAT...LON 4420 9304 4412 9218 4339 9166 4264 9161
4270 9208 4291 9208 4291 9303
TIME...MOT...LOC 1944Z 198DEG 44KT 4322 9238
DABThe La Crosse radar (KARX), 55 km away, was scanning. The volume nearest the first event began at 20:02 UTC.
41 thunderstorm wind, 6 flood, 4 hail, 1 tornado. Local standard time, as filed.
Runoff from heavy rains pushed the Trempealeau River out of its banks in Arcadia. The river crested a foot and a half above the flood state at 9.5 feet.
Numerous trees were blown down on houses and cars in Trempealeau.
Trees were blown down on Brice Prairie. One large tree fell on a camper and destroyed it.
A roof was blown off a garage in Midway.
An estimated 60 mph wind gust occurred in Holmen.
Pine trees were snapped east of Galesville.
A farm outbuilding was destroyed west of Galesville.
A section of a large barn was destroyed east of Galesville. Part of the destroyed roof was blown about a quarter mile away.
An EF-1 tornado moved across far southeast Trempealeau County and damaged trees and farm buildings. One barn was destroyed, part of a metal roof was taken off an outbuilding and a tree was knocked over onto the roof of a mobile home.
East of Galesville, a large metal grain bin was flattened and moved several hundred yards.
East of Galesville, a portion of a large tree was blown down. As the tree came down, it damaged the roof of a house.
Trees were blown down just north of North Bend.
Several large trees were blown down west of Cashton.
Several large trees were blown down in Sparta.
Numerous trees were blown down just north of Black River Falls.
Trees were blown down along State Highway 56 in Gillingham.
Trees were blown down in Hillsboro. One downed tree took out a light pole.
Several large trees were blown down in Tomah.
An estimated 60 mph wind gust occurred in Tomah.
Numerous trees were blown down across the southwest part of Clark County.
An estimated 65 mph wind gust occurred on the west side of Tomah that damaged signs near the fairgrounds.
An estimated 60 mph wind gust occurred just north of Abbotsford.
Trees were blown down west of Medford.
An estimated 70 mph wind gust occurred in Glen Haven that blew down a machine shed.
An estimated 60 mph wind gust occurred in Cassville.
An 80 mph wind gust occurred in Patch Grove.
An estimated 62 mph wind gust occurred near Bridgeport that blew down trees and power lines.
Trees were blown down on the north side of Prairie du Chien. Some of these trees landed on houses and cars. Some roof damage also occurred in the strong winds.
An estimated 70 mph wind gust occurred in Lancaster. Several barns and outbuildings were blown down and destroyed across the southwest half of Grant County as the line storms moved across. Lots of power lines were also down.
A couple of machine sheds were blown down north of Prairie du Chien.
A 71 mph wind gust occurred east of Stitzer.
Trees and power lines were blown down northwest of Port Andrews.
A barn was destroyed when it was blown off its foundation west of Liberty Pole.
Trees were blown down southwest of Viroqua. Some of these trees landed on houses.
Trees were blown down over the southeast part of Vernon County.
An estimated 65 mph wind gust occurred in Viola.
An estimated 65 mph wind gust occurred north of Yuba.
An estimated 60 mph wind gust occurred in Melvina.
A path of straight line wind damage was found from the east of Lake Neshonoc to northwest of Bangor. Approximately 250 trees were damaged or uprooted, a barn was destroyed, another barn lost part of its roof and there was minor damage to a house and garage.
A barn was destroyed south of Mauston.
Several trees and power lines were blown down in Mauston.
Trees were blown down in Hustler.
Trees were blown down in Easton.
Runoff from heavy rains pushed the Black River out of its banks in Black River Falls. The river crested almost three feet above the flood stage at 49.73 feet.
Runoff from heavy rains pushed the Trempealeau River out of its banks in Dodge. The river crested almost three feet above the flood stage at 11.98 feet.
Runoff from heavy rains caused the operators of the Castle Rock Dam to release above normal amounts of water. The flow peaked at 36,613 cubic feet per second (cfs) and flood stage is considered to be 30,000 cfs.
Runoff from heavy rains pushed the Black River out of its banks near Galesville. The river crested almost a foot and a half above the flood stage at 13.39 feet.
Runoff from heavy rains pushed the Yellow River out of its banks in Necedah. The river crested around a foot and a half above the flood stage at 16.59 feet.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2017Every state in 2017This day in weather historyThe tornado archive for Wisconsin, 2017Warnings in Wisconsin, May 2017
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: 702295, 697773, 697752, 700364, 697757, 697755, 699986, 699988, 699977, 699989, 699990, 697760, 699251, 697762, 699518, 697764, 697771, 697772, 697774, 699517, 698625, 698628, 700551, 698638, 698644, 699056, 699057, 699058, 699067, 699059, 702275, 699072, 702277, 699074, 699121, 699979, 702270, 699122, 699123, 699124, and more.