Alert archive / Michigan / Flash Flood Warnings in 2011

Flash Flood Warning 2, NWS Detroit, MI

May 29, 2011Shiawassee County, Michigan

NWS Detroit, MI issued this flash flood warning at May 29, 2011, 5:55 PM EDT for Shiawassee 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
May 29, 2011, 5:55 PM EDT (21:55 UTC)
Expired
May 29, 2011, 7:56 PM EDT
In force
2 hr
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Flood severity
None

County Shiawassee County, MI

The radar

The Detroit radar (KDTX), 67 km from the middle of the area, began a volume at 21:58 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
May 29, 7:30 PM EDTHEAVY RAIN 1Corunna, MI1 INCH OF RAIN IN 2 HOURS. RIVER HAS RISEN SIGNIFICANLY.
May 29, 7:53 PM EDTHEAVY RAIN 1Corunna, MIONE INCH OF RAIN IN UNDER TWO HOURS.

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, 9.9 hours before the alert went out and 69 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 2011-05-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 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 2011-05-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 square meters per square second.19395878Sfc1 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
12 J/kg
Mixed-layer CIN
-294 J/kg
Mixed-layer LCL
499 m above ground
0-6 km bulk shear
64 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
298 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

812 
WGUS53 KDTX 292155
FFWDTX
MIC155-300400-
/O.NEW.KDTX.FF.W.0002.110529T2155Z-110530T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
555 PM EDT SUN MAY 29 2011

THE NATIONAL WEATHER SERVICE IN DETROIT/PONTIAC HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SHIAWASSEE COUNTY IN SOUTHEAST MICHIGAN...

* UNTIL MIDNIGHT 

* AT 553 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A COMPLEX OF THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE     
  WARNED AREA. RADAR ESTIMATES BETWEEN A HALF INCH AND 1.5 INCHES OF 
  RAIN HAS ALREADY FALLEN.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  DURAND...LAINGSBURG...NEW LOTHROP...OWOSSO...PERRY...BANCROFT...   
  BYRON...CORUNNA...HENDERSON...LENNON AND MORRICE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THUNERSTORMS WILL CONTINUE FOR AT LEAST ANOTHER HOUR BEFORE MOVING 
OFF TO THE EAST. ADDITIONAL RAINFALL AMOUNTS OF ONE TO TWO INCHES 
ARE POSSIBLE IN THE WARNED AREA.

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4313 8437 4313 8393 4278 8392 4277 8436

$$

SC
2 follow-up statements
040 
WGUS73 KDTX 292239
FFSDTX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
639 PM EDT SUN MAY 29 2011

MIC155-300400-
/O.CON.KDTX.FF.W.0002.000000T0000Z-110530T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SHIAWASSEE MI-
639 PM EDT SUN MAY 29 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SHIAWASSEE COUNTY UNTIL
MIDNIGHT EDT...

AT 638 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
HEAVY RAIN OVER THE AREA. RAINFALL AMOUNTS ARE ESTIMATED BETWEEN ONE 
AND TWO INCHES OVER THE PAST TWO HOURS. RAINFALL WILL DIMINISH OVER 
THE NEXT HOUR. ADDITIONAL RAINFALL AMOUNTS SHOULD BE LESS THAN A 
HALF AN INCH. 

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE...
DURAND...LAINGSBURG...NEW 
LOTHROP...OWOSSO...PERRY...BANCROFT...BYRON...CORUNNA...HENDERSON...L
ENNON AND MORRICE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLOODING OF SMALL CREEKS
AND STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES... AS WELL AS
FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4313 8437 4313 8393 4278 8392 4277 8436

$$

SC
278 
WGUS73 KDTX 292356
FFSDTX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
756 PM EDT SUN MAY 29 2011

MIC155-300011-
/O.CAN.KDTX.FF.W.0002.000000T0000Z-110530T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SHIAWASSEE MI-
756 PM EDT SUN MAY 29 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SHIAWASSEE COUNTY
IS CANCELLED...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO
RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4313 8437 4313 8393 4278 8392 4277 8436

$$

SC

The office that day

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

IssuedProductOfficeCountiesLasted
May 29, 11:26 AM EDTFlood WatchDTXGenesee, Lapeer, Lenawee, Livingston, Macomb, Monroe and 5 more8 hr
May 29, 4:41 PM EDTSevere Thunderstorm WarningDTXLenawee69 min
May 29, 4:55 PM EDTTornado WarningDTXLenawee56 min
May 29, 5:02 PM EDTTornado WarningDTXLivingston, Washtenaw53 min
May 29, 5:04 PM EDTSpecial Marine WarningDTX71 min
May 29, 5:18 PM EDTSevere Thunderstorm WarningDTXMonroe87 min
May 29, 5:22 PM EDTTornado WarningDTXGenesee, Shiawassee83 min
May 29, 5:28 PM EDTSevere Thunderstorm WarningDTXOakland77 min
May 29, 5:30 PM EDTSpecial Marine WarningDTX75 min
May 29, 5:36 PM EDTTornado WarningDTXMonroe45 min
May 29, 5:46 PM EDTSevere Thunderstorm WarningDTXWayne34 min
May 29, 5:47 PM EDTTornado WarningDTXOakland42 min
May 29, 5:57 PM EDTSevere Thunderstorm WarningDTXLapeer78 min
May 29, 6:13 PM EDTSevere Thunderstorm WarningDTXMacomb, Saint Clair36 min
May 29, 6:16 PM EDTSpecial Marine WarningDTX66 min

Nearby

Flash Flood Warnings in Michigan, 2011Every flash flood warning in 2011

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.