Thunderstorms developed during the early morning hours of July 7th across portions of northeast Iowa. These storms formed along a nearly stationary front that was in place across the region.
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.
Thunderstorms developed during the early morning hours of July 7th across portions of northeast Iowa. These storms formed along a nearly stationary front that was in place across the region. The storms produced wind damage in Osage (Mitchell County), New Hampton (Chickasaw County) and Decorah (Winneshiek County).
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 Jul 7, 1:49 AM CST, 13 minutes earlier.
Area Forecast Discussion National Weather Service La Crosse WI 249 AM CDT THU JUL 7 2016 .SHORT TERM...(Today through Tonight) Issued at 249 PM CDT THU Jul 7 2016 Surface analysis at 2 am had a warm front draped west-east from northern IA into far south WI. Rich theta-e air advecting northeast out of the Plains into/over the warm front, combined with a weak mid- level trough was producing a fairly strong QLCS across southern MN into central/western IA. This line was racing east around 40 mph and should be into southeast MN/northeast Ia by 3 am, then gradually weakening as it crosses east of the Mississippi River after 4 am. Will see that QLCS mostly pushed east out of the area by mid- morning, leaving a brief quiet period from late morning into the early afternoon. Increasing moisture transport into the area ahead of low pressure pushing out of the Plains expected to produce scattered shower/thunderstorm through the afternoon. Expect these storms to gradually ramp up going into late afternoon/early evening as cold front pushes from MN/IA. Plenty of CAPE will work with 0-3km bulk shear of 25-35kt for strong to severe storm potential... damaging wind being the main threat. Current thinking is there will be a fairly solid line of incoming storms with the front but there may be a northern mechanically/pva forced component and a southern/more thermodynamically-driven component as the front rolls in. In theory then, it is quite possible that the line of storms may split north south of I-90 during the early evening. Have left mostly likely pops in for the entire area for now/highest north with the pva, but wanted to convey the possibility of the split. Expecting the cold front/bulk of storms to lift northeast of I-94 after midnight. .LONG TERM...(Friday through Wednesday) Issued at 249 PM CDT THU Jul 7 2016 Friday will see a continued chance of showers and storms mainly northeast of I-94 along with fairly breezy northwest winds in cyclonic flow behind low pressure over the Upper Peninsula. Cooler and drier otherwise with highs in the 70s. High pressure builds in for the weekend for a dry/cooler spell. Shower/thunder chances returns Monday through Wednesday as low pressure tracking across the Northern Plain into southern Canada pushes a cold front toward/through the region. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) Issued at 1100 PM CDT Wed Jul 6 2016 Still some uncertainty with how the area of thunderstorms moving east/southeast out of the northern plains will evolve-track overnight. Latest NAM joins the EC with taking the activity more southeast - away from the taf sites. Mesomodels though still favor bringing some shra/ts across krst/klse in the 09-12z (or so) time frame. HRRRs doing the best with current convection and will lean toward that solution for now. Will stay optimistic with cigs, keeping it predominately VFR. Somewhat variable clouds tomorrow with winds likely from an easterly direction Thu. Another round of shra/ts for the region Thu evening, but some hints that most of the activity could move north and south of the taf sites. Confidence not high on how this will evolve...with any lingering morning convection playing an important role. Will add vcts for the moment, but expect some refinement to this forecast through the day Thu. && .ARX Watches/Warnings/Advisories... WI...None. MN...None. IA...None. && SHORT TERM...DAS LONG TERM....DAS AVIATION...Rieck
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LA CROSSE WI 923 AM CDT WED JUL 6 2016 IAZ008>011-018-019-029-030-MNZ079-086>088-094>096-WIZ017-029- 032>034-041>044-053>055-061-071200- 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- 923 AM CDT WED JUL 6 2016 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST IOWA...SOUTHEAST MINNESOTA...AND CENTRAL INTO SOUTHWEST WISCONSIN. .DAY ONE...THIS AFTERNOON AND TONIGHT THUNDERSTORMS ARE EXPECTED TO DEVELOP NORTHWARD INTO THE AREA LATER TONIGHT. WHILE CONFIDENCE REMAINS RATHER LOW ABOUT HOW WIDESPREAD THUNDERSTORMS WILL BECOME...ANY STORMS THAT DEVELOP COULD BE STRONG WITH GUSTY WINDS...HAIL...AND TORRENTIAL DOWNPOURS...ESPECIALLY ACROSS NORTHEAST IOWA. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY ONE OR TWO ADDITIONAL ROUNDS OF THUNDERSTORMS ARE EXPECTED ACROSS THE AREA THURSDAY INTO FRIDAY. STORMS MAY BECOME SEVERE THURSDAY AFTERNOON INTO THURSDAY NIGHT AND MAY ALSO PRODUCE LOCALIZED HEAVY RAINS. THUNDERSTORMS ARE AGAIN POSSIBLE NEXT MONDAY AND TUESDAY. AT THIS TIME...IT REMAINS TOO EARLY TO DETERMINE THE RISK FOR SEVERE WEATHER. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY BUT MAY BE NEEDED THURSDAY INTO THURSDAY NIGHT. .EMERGENCY MANAGEMENT COORDINATION... NO WEBINAR IS SCHEDULED. LAWRENCE/DAS/BOYNE
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LA CROSSE WI 225 AM CDT THU JUL 7 2016 IAZ008-009-018-019-MNZ079-086-087-094-095-070900- CHICKASAW-FLOYD-MITCHELL-HOWARD-DODGE-WABASHA-MOWER-FILLMORE-OLMSTED- 225 AM CDT THU JUL 7 2016 ...AN AREA OF STRONG THUNDERSTORMS MOVING INTO SOUTHEAST MINNESOTA AND NORTHEAST IOWA THROUGH 4 AM... AT 223 AM CDT...RADAR INDICATED STRONG THUNDERSTORMS WERE LOCATED ALONG A LINE EXTENDING FROM NEAR WALDORF TO NEAR FOREST CITY TO NEAR IOWA FALLS. MOVEMENT WAS EAST AT 50 MPH. WINDS IN EXCESS OF 40 MPH AND HALF INCH HAIL ARE POSSIBLE WITH THESE STORMS. THROUGH 4 AM...LOCATIONS IMPACTED INCLUDE... ROCHESTER...AUSTIN...CHARLES CITY...CRESCO...OSAGE...NEW HAMPTON... DODGE CENTER...PRESTON...MANTORVILLE...STEWARTVILLE...BYRON... PLAINVIEW...PINE ISLAND...CHATFIELD... SPRING VALLEY...EYOTA... NASHUA AND NORA SPRINGS. FREQUENT CLOUD TO GROUND LIGHTNING AND QUICK RAINFALL AMOUNTS UP TO ONE INCH CAN ALSO BE EXPECTED WITH THESE STORMS. IF OUTDOORS OR CAMPING, SEEK A SAFE SHELTER INSIDE A BUILDING OR VEHICLE. LAT...LON 4420 9305 4419 9208 4291 9208 4291 9302 TIME...MOT...LOC 0723Z 265DEG 48KT 4388 9368 4330 9355 4255 9332 LAWRENCE
The La Crosse radar (KARX), 144 km away, was scanning. The volume nearest the first event began at 08:02 UTC.
3 thunderstorm wind. Local standard time, as filed.
Several large tree branches were blown down in Osage.
Numerous large tree branches were blown down in New Hampton.
A large tree branch was blown down in Decorah.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2016Every state in 2016This day in weather historyWarnings in Iowa, July 2016
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: 646574, 646575, 646576.