An area of low pressure slowly tracked east across east-central Wisconsin to central Lake Michigan through the day on Friday (7/5). Showers and thunderstorms developed shortly after daybreak and then became more concentrated during the mid-morning into the early 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 GRB wrote it up.
An area of low pressure slowly tracked east across east-central Wisconsin to central Lake Michigan through the day on Friday (7/5). Showers and thunderstorms developed shortly after daybreak and then became more concentrated during the mid-morning into the early afternoon. A cluster of showers and thunderstorms became slow moving over Waupaca County, resulting in 4 to 6 inches of rain with the city of Manawa measuring 5.7 inches of rain. This rain, coupled with the impacts from around 6 inches of recent rain from the two weeks prior, led to the failure of the Manawa Dam, as water overtopped the dam around 12:30 PM CDT. This led to evacuations of residences and businesses in Manawa and downstream of the dam into the town of Royalton. Additionally, several water rescues of people trapped in vehicles were made during the morning, especially in Manawa and Appleton. A Boil Water advisory was also issued for Manawa and surrounding areas. Heavy rainfall of 2 to 3 inches also caused flash flooding in portions of Outagamie, Calumet, and Brown counties during the afternoon.
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 Green Bay, WI wrote its last area forecast discussion before the first event at Jul 5, 5:41 AM CST, 3 hours 49 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Green Bay WI 641 AM CDT Fri Jul 5 2024 Updated aviation portion for 12Z TAF issuance .KEY MESSAGES... - Areas of showers and some thunderstorms are expected today. The primary threat from storms will be locally heavy downpours. - River and stream levels will remain elevated into the weekend. - On and off chances for rain/storms continue through early next week as upper-level flow remains unsettled. && .DISCUSSION... Issued at 302 AM CDT Fri Jul 5 2024 Short Term...Today...Tonight...and Saturday Shower and thunderstorm coverage into this evening is primary focus in the short term. Mid-level low is spinning over southern MN while weak sfc low is over southwest WI. Arc of showers and isolated thunder is crossing northeast WI with area of steadier and heavier showers over northern WI into central MN. Thus far this system has drastically underperformed in our CWA in terms of rainfall amounts and heavy rainfall potential, so that limits the flooding risk going forward. Think lighter QPF thus far is due in part to limited instability to boost rainfall rates by time the showers reached our area last evening and also PWATS barely up to 1.50 inches which is only up to 125 percent of normal. Do expect showers to increase this morning into the afternoon as the mid- level low tracks across the area. Thunder has been quite limited so far but do expect an uptick in thunder toward daybreak this morning as theta-e advection and elevated instability combine ahead of the mid-level low and sfc low. Best chance for thunder impacting more of the area though will occur late morning into the afternoon as the lift from the mid-level low and steeper lapse rates/MLCAPEs building to 800J/kg interact with some daytime "heating" (relative term as highs today will be below normal in the mid 60s north to the lower 70s south). Following MLCAPEs, expect thunder potential all areas through midday then shifting to mainly south of highway 29 the rest of the afternoon. Wind fields are not strong with the system as mid-upper jets are displaced to the east and southeast over the central Great Lakes. Thus effective shear is weak so am not expecting any severe weather. Heavy downpours would be the main threat from storms as PWATs don't change much from what they are early this morning. Lingering showers end early, then it turns mainly dry tonight. Cool advection in wake of the trough and departing sfc low will keep skies partly to mostly cloudy. Hint of some sprinkles at times northeast WI, ending by daybreak Sat. Majority of Sat looks dry, but with approaching shortwave trough and weak warm air advection resulting in MLCAPEs reaching 500-1000J/kg, did include small chances for showers and storms most areas during peak heating. Also is signal for convergence along Michigan lake breeze which could also support pop-up shower or storm later Saturday, very isolated coverage. That said even with these small chances for rain, plenty of dry time is expected on Saturday with highs bouncing back into the mid 70s lakeside to low 80s inland. Long Term...Saturday Night Through Thursday Not many changes to the extended as an active pattern remains through the middle of next week. Next chances for moderate rain will arrive Sunday afternoon, becoming more robust into Monday morning. There is still uncertainty regarding rainfall amounts, although current ensemble guidance seems to hone in on east- central Wisconsin to receive the bulk of the precip. Definitely worth keeping an eye on given that east-central Wisconsin is currently vulnerable to flooding given recent bouts of heavy rain. Weekend precip chances... As upper-level ridging over the Pacific struggles to build onshore, much of the central CONUS will be left under a persistent troughing regime through mid-week. This pattern will maximize opportunities for perturbations/weak impulses to bring chances for rain and storms to the forecast area. Best chances look to be Sunday afternoon through Monday morning as a surface low and attendant cold front track across the upper Mississippi Valley. Moisture content appears to be favorable for periods of moderate to heavy rain during this time as a surge of Gulf moisture places a narrow corridor of 1.75 inch PWATs (~125% of normal) along the lakeshore. Some diurnally-driven storms will also be possible Sunday afternoon and evening as resultant instability exceeds 1,000 J/kg. However, the big question will be whether or not the bullseye of highest rainfall misses off to the east over the lake. Rest of the extended... Rain/storm chances will continue through Wednesday as several embedded impulses circulate through a longwave trough. An end to the current wet pattern may then be in sight toward the end of the extended as long-range models show upper-level ridging settling in across the CONUS. This may signal the beginning of a warmer/drier summer pattern, although only time will tell. && .AVIATION...for 12Z TAF Issuance Issued at 640 AM CDT Fri Jul 5 2024 A mid level low and sfc low will move slowly from southern Minnesota to northern Wisconsin and produce occasional showers and isolated thunderstorms today. The activity will diminish this evening as it settles south of Wausau to Green Bay and Manitowoc. Flight conditions are variable to start the TAF period with mainly MVFR to VFR. Expect some lowering to mainly IFR/MVFR today with greatest risk of IFR farther inland from Lake Michigan. Ceilings and visibilities will improve later this afternoon into this evening. && .GRB WATCHES/WARNINGS/ADVISORIES... None. && DISCUSSION.....JLA/Goodin AVIATION.......JLA
Hazardous Weather Outlook National Weather Service Green Bay WI 316 AM CDT Fri Jul 5 2024 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-060830- Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln- Langlade-Menominee-Northern Oconto County-Door-Marathon-Shawano- Wood-Portage-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago- Calumet-Manitowoc-Southern Marinette County- Southern Oconto County- 316 AM CDT Fri Jul 5 2024 This Hazardous Weather Outlook is for north-central and northeast Wisconsin. .DAY ONE...Today and Tonight There is a chance of thunderstorms today. The greatest chance for storms this afternoon will be south of highway 29. Severe storms are not expected, but locally heavy rain is possible in any stronger storms. Some rivers and streams will continue to run above bankfull due to recent and expected rainfall. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Some rivers and streams will continue to run above bankfull due to recent and expected rainfall. On and off chances for showers and thunderstorms will continue through early next week. Although the severe weather threat is low, locally heavy rainfall will be possible. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight. LMZ521-522-541>543-060830- The Bay of Green Bay south of a line from Cedar River MI to Rock Island Passage-Lake Michigan from Washington Island to Sheboygan- 316 AM CDT Fri Jul 5 2024 This Hazardous Weather Outlook is for portions of northwest Lake Michigan and the waters of Green Bay. .DAY ONE...Today and Tonight Thunderstorms are possible today. Any thunderstorms will pose a threat to mariners. .DAYS TWO THROUGH SEVEN...Saturday through Thursday On and off chances for thunderstorms are possible through early next week. Any thunderstorms will pose a threat to mariners. JLA/Goodin
Preliminary Local Storm Report
National Weather Service Green Bay WI
745 AM CDT Fri Jul 5 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0700 AM Rain 1 NNE Boulder Junction 46.13N 89.62W
07/05/2024 M1.43 Inch Vilas WI Cocorahs
Cocorahs station WI-VL-14 Boulder Junction 1.4 NE.
0700 AM Rain 6 NNE Boulder Junction 46.20N 89.60W
07/05/2024 M1.40 Inch Vilas WI Cocorahs
Cocorahs station WI-VL-25 Presque Isle 7.0 ESE.
0700 AM Rain 1 SSE Manitowish Waters 46.12N 89.88W
07/05/2024 M1.29 Inch Vilas WI CO-OP Observer
CO-OP Observer station RLKW3 Manitowish Waters 0.6 S.
0715 AM Rain 1 S Manitowish Waters 46.12N 89.88W
07/05/2024 M1.02 Inch Vilas WI AWOS
AWOS station KD25 Manitowish Waters Airport.
&&
24-hour rain totalsPreliminary Local Storm Report
National Weather Service Green Bay WI
752 AM CDT Fri Jul 5 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0700 AM Rain 2 E Ogdensburg 44.46N 88.98W
07/05/2024 M1.24 Inch Waupaca WI Cocorahs
Cocorahs station WI-WP-3 Ogdensburg 2 E.
0725 AM Rain 3 E Winchester 46.23N 89.83W
07/05/2024 M1.15 Inch Vilas WI Mesonet
Mesonet station EW6920 Winchester.
0500 AM Rain 1 WNW Iola 44.50N 89.13W
07/05/2024 M1.02 Inch Waupaca WI Cocorahs
Cocorahs station WI-WP-11 Iola 0.4 SSW.
&&
24-hour rain totalsPreliminary Local Storm Report
National Weather Service Green Bay WI
1011 AM CDT Fri Jul 5 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1010 AM Rain 1 WSW Manawa 44.46N 88.92W
07/05/2024 M2.80 Inch Waupaca WI Public
Since 830 AM this morning.
&&The Green Bay radar (KGRB), 62 km away, was scanning. The volume nearest the first event began at 15:27 UTC.
4 flash flood. Local standard time, as filed.
Rainfall amounts of 4 to 6 inches, combined with the failure of the Manawa Dam, caused flooding in Manawa during the late morning and early afternoon.
Rainfall amounts of 2 to 3 inches in the Appleton area during the early afternoon caused 1 to 2 feet of flowing water in some locations.
Rainfall of 2 to 3 inches in southwestern Brown County caused street flooding along with road closures and stranded vehicles during the afternoon in Greenleaf.
Rainfall of 2 to 3 inches in northeastern Calumet County caused street flooding along with road closures and stranded vehicles during the afternoon in Hilbert.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2024Every state in 2024This day in weather historyWarnings in Wisconsin, July 2024
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: 1181512, 1185563, 1185593, 1185592.