Record high lake levels on Lake Michigan caused some isolated flooded areas near the lake on an ongoing basis.
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.
Record high lake levels on Lake Michigan caused some isolated flooded areas near the lake on an ongoing basis.
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 May 31, 10:47 PM CST, 1 hour 13 minutes earlier.
Area Forecast Discussion National Weather Service Green Bay WI 1147 PM CDT Sun May 31 2020 Updated aviation portion for 06Z TAF issuance .SYNOPSIS... Issued at 315 PM CDT Sun May 31 2020 Turning much warmer and more humid the new few days with some showers and thunderstorms at times. The upper pattern across North America will flatten to a nearly zonal regime the next few days, then undergo reamplification during the latter part of the period. By next weekend we will be back with a pattern similar to what we had a couple days ago-- troughs near the coasts and a mid-continent ridge. The switch to zonal flow will bring much warmer air from the Plains into the forecast area the next few days. The humidity will increase substantially as well. Temperatures will trend downward by next weekend. How far they fall will depend on exactly how far west the reamplifying ridge sets up, and how sharp it becomes. The pattern will be favorable for AOA normal precipitation during the 7 day period. && .SHORT TERM...Tonight and Monday Issued at 315 PM CDT Sun May 31 2020 Main focus is on thunderstorms and severe potential for Monday. Clear blue skies across the area today. Satellite imagery at 19Z showed a thin line of mid-clouds moving into north- central WI which will move across parts of the area this afternoon. Otherwise, expect mainly clear skies to persist through the evening. Tonight...Cloud cover increases from west to east after midnight as 850 flow backs to the southwest and there is a return of low level moisture. Showers are expected to hold off until Monday morning. With the return of clouds and warmer air, temperatures will initially fall, then likely level off after midnight. Therefore, temperatures will not be as cold tonight, with lows in the upper 40s and lower 50s. Monday...Meso models showing two main rounds of showers/storms to move across the area. The first is associated with an 850 warm front during the mid to late morning. Lighter rain showers seem most likely during the morning as there is not much instability present yet. However, with CAPE values around 100 to 300 J/kg, some isolated thunder is possible. Then, a mid-level shortwave slides across northern WI during the afternoon, which will be the main driver for thunderstorms from about 18Z/01 to 02Z/02. CAPE increases to around 500 to 1500 J/kg, and while forecast soundings show more of a skinny CAPE profile, 30 to 40 kts of sfc to 3km shear and mid-level lapse rates around 7.0 C/km is enough for some strong/severe storms to develop. Large hail is the main threat, but cannot rule out some strong thunderstorm wind gusts as well. With PWats around 1.40 to 1.60 inches locally heavy downpours will also be possible in any showers or storms. The SPC made minimal changes to the Day 2 Outlook for severe storms, current Marginal Risk across most of the GRB forecast area looks reasonable. Meanwhile, high temps will be near normal for June 1, with readings in the 70s for most of the area away from Lake Michigan. .LONG TERM...Monday Night Through Sunday Issued at 315 PM CDT Sun May 31 2020 The storms from Monday will probably linger in the east at least early Monday evening before ending. A short period of quiet weather is likely while the forecast area is in the warm sector of a cyclone passing through well north of the area. The chance for thunderstorms will increase again Tuesday evening as a cool front sags south through the area. Low-level flow and convergence near the boundary looks weak, but steep mid-level lapse rates will be present as the remnants of an elevated mixed layer pass across the area. Shear will also be modest. The guidance offered varying ideas on whether storms would fire across northern or central Wisconsin before sagging south with the front. The latter is more likely, though definitely far from certain. Mentioned the severe risk in the HWO. High PWATs (up to 2 SDs above normal) will also support a heavy rainfall threat. The uncertainty regarding precipitation chances during the remainder of the period is rather high given the zonal flow and then questions as to the exact structure/position of the amplifying upper ridge next weekend. && .AVIATION...for 06Z TAF Issuance Issued at 1146 PM CDT Sun May 31 2020 VFR flight conditions are expected through the overnight hours. Mid level clouds will spread in ahead of the next wave to produce showers and thunderstorms later on Monday. Light rain showers are possible starting mid morning (after 13Z or so) across central and north-central WI, and starting late morning across the east (after 16Z or so). Cigs will then fall to MVFR to occasional IFR Monday afternoon. Thunderstorms are also possible Monday afternoon and evening. Some LLWS is expected across east-central Wisconsin Monday evening after the showers exit the region as the low level jet increases out of the southwest at 40 to 45 knots. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && SYNOPSIS.......Skowronski SHORT TERM.....KLJ LONG TERM......Skowronski AVIATION.......Kurimski
Hazardous Weather Outlook National Weather Service Green Bay WI 234 PM CDT Sun May 31 2020 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-011945- 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- 234 PM CDT Sun May 31 2020 This Hazardous Weather Outlook is for north-central and northeast Wisconsin. .DAY ONE...Tonight No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Monday through Sunday There is a chance of thunderstorms Monday through Monday evening. A few of the storms could produce large hail and heavy rainfall. Increasing south winds will cause building waves which will lead to a high swim risk along the Lake Michigan shoreline Monday afternoon into Monday evening. Another round of thunderstorm is possible Tuesday evening and Tuesday night, especially across central and east-central Wisconsin. Some of the storms could be severe and produce large hail and damaging winds. Heavy rainfall is also possible. Thunderstorms will be possible at times through the remainder of the week and during next weekend. It is too early to determine whether any of these storms could be severe. Runoff from recent rainfall will continue to produce fast flows and high water levels on rivers and streams across eastern Wisconsin through mid-week. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed tonight. LMZ521-522-541>543-011945- The Bay of Green Bay south of a line from Cedar River MI to Rock Island Passage-Lake Michigan from Washington Island to Sheboygan- 234 PM CDT Sun May 31 2020 This Hazardous Weather Outlook is for portions of northwest Lake Michigan and the waters of Green Bay. .DAY ONE...Tonight Winds and waves will produce conditions requiring small craft on the Bay of Green Bay to exercise extra caution through early this evening. .DAYS TWO THROUGH SEVEN...Monday through Sunday Increasing southerly flow may lead to hazardous conditions for small craft on Lake Michigan Monday afternoon into Monday evening. Thunderstorms could pose a hazard to boaters at times during the upcoming week. Dense fog could also pose a hazard to boaters late Monday night through Wednesday, especially on Lake Michigan. KLJ/Skowronski
The national radar mosaic for the moment the first event began.
2 flood. Local standard time, as filed.
Areas around the Kewaunee Marina were often under water due to record high lake levels.
North Bayshore Road and County Highway Y from Harbor Road to County Highway A are closed due to ongoing flooding from record high lake levels.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2020Every state in 2020This day in weather historyWarnings in Wisconsin, June 2020
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: 889208, 889213.