Alert archive / Michigan / Flash Flood Warnings in 2021

Flash Flood Warning 9, NWS Detroit, MI

August 27, 2021Wayne County, Michigan

NWS Detroit, MI issued this flash flood warning at Aug 27, 2021, 1:56 PM EDT for Wayne County, Michigan. It was in force for 2 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 27, 2021, 1:56 PM EDT (17:56 UTC)
Expired
Aug 27, 2021, 4:14 PM EDT
In force
2 hr
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Flood severity
None

County Wayne County, MI

The radar

The Detroit radar (KDTX), 54 km from the middle of the area, began a volume at 17:58 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Aug 27, 1:56 PM EDTFLOOD5 Ne Downtown Detroit, MII94 ALL LANED CLOSED AROUND CONNER ST INTERSECTION
Aug 27, 3:16 PM EDTHEAVY RAIN 1.816 Ene Detroit, MI3 HOUR TOTAL RAINFALL MEASURED AT KDET DETROIT CITY AIRPORT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 5.9 hours before the alert went out and 53 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 12:00Z on 2021-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 319 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 12:00Z on 2021-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
319 J/kg
Mixed-layer CIN
-61 J/kg
Mixed-layer LCL
912 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

496 
WGUS53 KDTX 271756
FFWDTX
MIC163-272100-
/O.NEW.KDTX.FF.W.0009.210827T1756Z-210827T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Detroit/Pontiac MI
156 PM EDT Fri Aug 27 2021

The National Weather Service in Detroit/Pontiac has issued a

* Flash Flood Warning for...
  Northeastern Wayne County in southeastern Michigan...

* Until 500 PM EDT.

* At 156 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. The expected rainfall rate is 1.5 to 2.5 inches in 1 
  hour. Additional rainfall amounts up to 2 inches are possible in 
  the warned area. Flash flooding is ongoing or expected to begin 
  shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Grosse Pointe, Downtown Detroit, Eastpointe, Hamtramck, Hazel 
  Park, Grosse Pointe Woods, Harper Woods, Highland Park, Grosse 
  Pointe Park, Grosse Pointe Farms, Northeast Detroit and Grosse 
  Pointe Shores.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4245 8286 4236 8288 4234 8299 4231 8308
      4245 8309

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1.5-2.5 INCHES IN 1 HOUR

$$

 Behnke
2 follow-up statements
871 
WGUS73 KDTX 271847
FFSDTX

Flash Flood Statement
National Weather Service Detroit/Pontiac MI
247 PM EDT Fri Aug 27 2021

MIC163-272100-
/O.CON.KDTX.FF.W.0009.000000T0000Z-210827T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne MI-
247 PM EDT Fri Aug 27 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 PM EDT THIS 
AFTERNOON FOR NORTHEASTERN WAYNE COUNTY...

At 247 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 1 and 2 inches of rain have 
fallen. Flash flooding is ongoing or expected to begin shortly. MDOT 
and media reported a freeway closure of I 94 near Conner.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
Warren, Grosse Pointe, Downtown Detroit, Eastpointe, Hamtramck, 
Hazel Park, Grosse Pointe Woods, Harper Woods, Highland Park, Grosse 
Pointe Park, Grosse Pointe Farms, Northeast Detroit and Grosse 
Pointe Shores.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4245 8286 4236 8288 4234 8299 4231 8308
      4245 8309

FLASH FLOOD...RADAR INDICATED

$$

 Behnke
229 
WGUS73 KDTX 272014
FFSDTX

Flash Flood Statement
National Weather Service Detroit/Pontiac MI
414 PM EDT Fri Aug 27 2021

MIC163-272024-
/O.CAN.KDTX.FF.W.0009.000000T0000Z-210827T2100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne MI-
414 PM EDT Fri Aug 27 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN WAYNE COUNTY...

The heavy rain has ended. Please continue to heed remaining road 
closures.

LAT...LON 4245 8286 4236 8288 4234 8299 4231 8308
      4245 8309

$$

The office that day

Everything else NWS Detroit, MI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 26, 9:34 PM EDTSmall Craft AdvisoryDTX30 hr
Aug 27, 4:04 AM EDTBeach Hazards StatementDTXHuron18 hr
Aug 27, 6:43 AM EDTSpecial Weather StatementDTXBay, Midland, Saginaw62 min
Aug 27, 8:32 AM EDTAreal Flood AdvisoryDTXSaginaw3 hr
Aug 27, 10:03 AM EDTAreal Flood AdvisoryDTXGenesee3 hr
Aug 27, 12:08 PM EDTSpecial Weather StatementDTXWayne67 min
Aug 27, 12:22 PM EDTSpecial Weather StatementDTXMacomb68 min
Aug 27, 12:47 PM EDTAreal Flood AdvisoryDTXOakland, Wayne3 hr
Aug 27, 12:57 PM EDTSpecial Weather StatementDTXMacomb63 min
Aug 27, 1:02 PM EDTSpecial Marine WarningDTX58 min
Aug 27, 1:12 PM EDTFlash Flood WarningDTXOakland, Wayne3 hr
Aug 27, 4:26 PM EDTAreal Flood WarningDTXWayne6 hr

Nearby

Flash Flood Warnings in Michigan, 2021Every flash flood warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.