A quick inch and half of rain in Downtown Detroit caused flooding of I-94.
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 DTX wrote it up.
A quick inch and half of rain in Downtown Detroit caused flooding of I-94.
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 Detroit, MI wrote its last area forecast discussion before the first event at Jun 30, 2:57 PM EST, 1 hour 37 minutes earlier.
Area Forecast Discussion National Weather Service Detroit/Pontiac MI 357 PM EDT Wed Jun 30 2021 .DISCUSSION... Positively tilted upper level trough remains overhead this afternoon while the first surface cold front stalls near the MI/OH border. The synoptic scale wave will migrate further south today as the impressive Canadian Prairie ridge becomes dislodged by a landfalling Pacific low. This translates into decreasing heights for much of Lower Michigan for the remainder of today. H8-H7 layer dewpoint progs depict a 0.15C/mi rearward extending frontal slope resulting in some convective saturation issues as the column undergoes minor drying this afternoon in the wake. Wind profiles are relatively zonal with a slight southerly component promoting dry advection processes, particularly in the mid-levels. PWATs continue to trend down to below 1.25 inches across the north while the delayed frontal passage preserves higher column moisture for areas along and south of I-94 (upwards of 1.75 inches) where prior convection finally exited. Should see a quick thermal rebound within the next two hours given long late-June days to help re-establish some instability. Hi-Res solutions suggest mixed-coverage of afternoon and evening showers/storms. Activity near the Tri-Cities will remain more isolated and pulsey while scattered to numerous multicellular clusters expand and lift into the Metro vicinity. Lapse rates are rather unimpressive CWA-wide restricting UVVs within a decently (speed) sheared environment (0-6 km bulk values 35-40 knots). The more saturated forecast soundings are located within the southern- tier counties, but exhibit some signs of elevated convection given marginal 925 mb capping. Still expect isolated to scattered storms to remain non-severe, but capable of producing isolated strong gusts and additional nuisance flooding. Highs top out in the low 80s, except for areas near the state-line where thicker cloud cover inhibits diurnal heating to the upper 70s. The upper low continues to dive south overnight with leading shortwave energy pivoting through the base. Associated CVA will support widely scattered additional precip overnight before the next cold FROPA approaches. H8 temperatures highlight the relative strength of this front given the sharp thermal gradient yielding the first major airmass transition in nearly a week. Active FGEN along/ahead of the frontal slope will force additional rainfall with embedded thunderstorm activity, particularly across the south where the better heating and instability reservoir resides, but storms will face some entrainment issues aloft. Highs should hold just below 80F to the south while north of M-59 maxes out in the low to mid 70s behind the front where H8 temperatures drop below 10C by late afternoon. Friday will be the first truly dry day for the area under modest NNE flow within the dry slot of the aforementioned upper level disturbance. The parent PV anomaly consolidates and spins through the Thumb and southern Lake Huron during the first half of the day, but antecedent dryness precludes any notable PoPs. Main topic besides temperatures falling 5-10F below climatological norms is afternoon mixed-layer gustiness. The boundary layer will expand above 800 mb and tap into +25 knot flow which producing periods afternoon gusts near 30 mph as the back edge of the upper low overspreads Lower Michigan. The inflection point of the upper jet crosses Friday night into Saturday with building heights on the periphery of the north-central CONUS anticyclone. Highs climb into 80s on Saturday as the ridge flattens/shears out over the Great Lakes throughout the weekend. MaxTs creep upwards daily with the hottest day expected either Sunday or Monday when H5 heights reach 588 dam over the upper Mississippi Valley and H8 temps near 21C ensure +90F readings. Low- amplitude ridge-running shortwaves ripple through Sunday afternoon and could touch off a few isolated showers before the next longwave feature drives a cold front through sometime within the Monday night to Tuesday timeframe brining widespread cooling rain. && .MARINE... An upper level short wave continues to drive a weak cold front south this afternoon. The front is currently sitting near Lake St Clair and will advance into Lake Erie by this evening. A secondary cold front drops across Lake Huron late tonight into Thursday morning. This front is associated with a deep upper low that brings a pool of colder Canadian air south into the central Great Lakes to finish out the workweek. This trailing cooler airmass will allow for an uptick in the post frontal northerly winds across the lakes on Thursday, especially southern Lake Huron. Peak wind gusts are expected to up in the low 20 knot range and which will also lead to a modest increase in waves on the south end of Lake Huron. Northerly winds will persist through Friday before steadily weakening as the gradient relaxes this weekend. && .PREV DISCUSSION... Issued at 132 PM EDT Wed Jun 30 2021 AVIATION... Slow-moving cold front continues to straddle between the I-69/M-59 corridors based on latest dewpoint trends, with the deeper instability and moisture axes focused further south into northern Ohio. Still, enough low-level moisture and meager instability will remain this afternoon south of the front to spark additional scattered showers with perhaps a few embedded thunderstorms, most likely to affect the Detroit terminals although confidence in occurrence is low. Convective activity still looks on track to peak in the 19z-23z timeframe, with a boost in diurnal heating, before waning and shifting further east/southeast out of the airspace. Generally VFR conditions prevail, although some low- lying pockets of MVFR stratus around the Detroit terminals may linger for an hour or two before lifting, with mainly MVFR conditions associated with any convection. Light southwest winds under 10 knots gradually veer to more of a westerly direction through late evening before turning more northerly late in the period. Additional widely scattered showers will be possible by 18z Thursday. For DTW...Showers will again be possible through much of the remainder of the afternoon into early this evening. Brunt of deeper moisture and instability has shifted off to the southeast, although still cannot rule out a thunderstorm over the terminal. Will continue to leave out thunderstorm mention for now, and make amendment as necessary if near term trends become more favorable. DTW THRESHOLD PROBABILITIES... * Moderate for ceiling at or below 5000 feet this afternoon. * Low for thunderstorms this afternoon into early this evening, focused 19z-23z. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. Lake Huron...NONE. Lake St Clair...NONE. Michigan waters of Lake Erie...NONE. && DISCUSSION...KK MARINE.......KDK AVIATION.....IRL You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.
Hazardous Weather Outlook National Weather Service Detroit/Pontiac MI 422 AM EDT Wed Jun 30 2021 MIZ047>049-053>055-060>063-068>070-075-076-082-083-010900- Midland-Bay-Huron-Saginaw-Tuscola-Sanilac-Shiawassee-Genesee-Lapeer- St. Clair-Livingston-Oakland-Macomb-Washtenaw-Wayne-Lenawee-Monroe- 422 AM EDT Wed Jun 30 2021 This hazardous weather outlook is for portions of southeast Michigan. .DAY ONE...Today and Tonight There is a chance of thunderstorms today as a cold front passes southward through the area. Though widespread severe weather is not expected, the cold front combined with a humid airmass and residual boundaries across the area may result in an isolated strong to severe storm. The primary threat with any storm would be damaging wind gusts and heavy rainfall. Storm motion will be easterly around 35 mph. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Additional thunderstorms will be possible Thursday as a disturbance dives southeast into the region from Canada. Severe weather is not expected. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today and tonight. LCZ460-LEZ444-LHZ361>363-421-422-441>443-462>464-010900- Lake St Clair- Michigan Waters of Lake Erie from Detroit River to North Cape MI- Lake Huron from 5NM east of Mackinac Bridge to Presque Isle Lt beyond 5 NM off shore- Lake Huron from Presque Isle Light to Sturgeon Point MI beyond 5NM off shore- Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off shore- Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner Saginaw Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI- Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI- Port Sanilac to Port Huron MI- Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore- Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore- Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore- 422 AM EDT Wed Jun 30 2021 This hazardous weather outlook is for portions of Lake Erie, Lake Huron and Lake St Clair. .DAY ONE...Today and Tonight There is a chance of thunderstorms today as a cold front passes southward through the area. Though widespread severe weather is not expected, the cold front combined with a humid airmass and residual boundaries across the area may result in an isolated strong to severe storm. The primary threat with any storm would be damaging wind gusts. Storm motion will be easterly around 30 knots. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday Additional thunderstorms will be possible Thursday as a disturbance dives southeast into the region from Canada. Severe weather is not expected. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today and tonight. You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit. DRK
Special Weather Statement
National Weather Service Detroit/Pontiac MI
457 PM EDT Wed Jun 30 2021
MIZ076-302200-
Wayne-
457 PM EDT Wed Jun 30 2021
...SPECIAL WEATHER STATEMENT...
At 454 PM EDT, a cluster of showers and thunderstorms was located
near Belle Isle, or near Grosse Pointe, moving east at 10 mph.
Winds in excess of 30 mph and very heavy rainfall are possible with
these storms.
This storm will be near...
Grosse Pointe around 505 PM EDT.
Other locations impacted by this storm include Northeast Detroit,
Highland Park, Northwest Detroit, Harper Woods, Grosse Pointe Shores,
Hamtramck, Grosse Pointe Woods, Grosse Pointe Park and Grosse Pointe
Farms.
Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.
LAT...LON 4236 8289 4235 8295 4234 8297 4237 8324
4244 8322 4245 8287
TIME...MOT...LOC 2054Z 282DEG 10KT 4240 8301
KDKThe national radar mosaic for the moment the first event began.
1 flood. Local standard time, as filed.
Flooding observed on east and westbound lanes of I-94 near Conner, as well as along I-94 overpasses on Detroit's east side.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Michigan in 2021Every state in 2021This day in weather historyWarnings in Michigan, June 2021
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: 970148.