Alert archive / Michigan / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Grand Rapids, MI

August 29, 2021Lake County, Michigan

NWS Grand Rapids, MI issued this flash flood warning at Aug 29, 2021, 2:33 PM EDT for Lake County, Michigan. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 29, 2021, 2:33 PM EDT (18:33 UTC)
Expired
Aug 29, 2021, 10:30 PM EDT
In force
8 hr
Issued by
NWS Grand Rapids, MI
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Lake County, MI

The radar

The Grand Rapids radar (KGRR), 118 km from the middle of the area, began a volume at 18:35 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.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 6.6 hours before the alert went out and 184 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, Green Bay/Straub, WI at 12:00Z on 2021-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1272 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, Green Bay/Straub, WI at 12:00Z on 2021-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 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
1272 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
845 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
216 m²/s²
Significant tornado parameter
1.3
Supercell composite
6.5

Open this sounding in Storm Lab

The text

As transmitted.

818 
WGUS53 KGRR 291833
FFWGRR
MIC085-300230-
/O.NEW.KGRR.FF.W.0001.210829T1833Z-210830T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Grand Rapids MI
233 PM EDT Sun Aug 29 2021

The National Weather Service in Grand Rapids has issued a

* Flash Flood Warning for...
  Southwestern Lake County in west central Michigan...

* Until 1030 PM EDT Sunday.

* At 233 PM EDT, Radar indicated that heavy rain has resulted in 
  significant rises on the Baldwin river.  Flooding was occurring 
  around Baldwin and Green Cottage.  Flash flooding is already 
  occurring.  The flooding will works its way down portions of the 
  Pere Marquette River.  It is possible that a small dam in the 
  upper portions of the Baldwin River may have been breached.

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding.

  SOURCE...Radar and automated gauges.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Baldwin and Idlewild.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. Act quickly to protect your life.

&&

LAT...LON 4393 8604 4393 8602 4393 8596 4387 8588
      4398 8577 4397 8571 4397 8570 4383 8585
      4389 8597 4390 8604 4391 8604 4392 8604

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

MJS
2 follow-up statements
644 
WGUS73 KGRR 292313
FFSGRR

Flash Flood Statement
National Weather Service Grand Rapids MI
713 PM EDT Sun Aug 29 2021

MIC085-300230-
/O.CON.KGRR.FF.W.0001.000000T0000Z-210830T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake MI-
713 PM EDT Sun Aug 29 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1030 PM EDT THIS 
EVENING FOR SOUTHWESTERN LAKE COUNTY...

At 713 PM EDT, Water levels along the Baldwin River downstream into 
the Pere Marquette River to the county line will continue to 
experience flooding.  No additional rain is predicted this evening

HAZARD...Life threatening flash flooding. Some evacuations have
         already occurred.

SOURCE...Trained spotters reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Baldwin and Idlewild.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now. Act quickly to protect your life.

&&

LAT...LON 4393 8604 4393 8602 4393 8596 4387 8588
      4398 8577 4397 8571 4397 8570 4383 8585
      4389 8597 4390 8604 4391 8604 4392 8604

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

MJS
317 
WGUS73 KGRR 300229
FFSGRR

Flash Flood Statement
National Weather Service Grand Rapids MI
1029 PM EDT Sun Aug 29 2021

MIC085-300239-
/O.EXP.KGRR.FF.W.0001.000000T0000Z-210830T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake MI-
1029 PM EDT Sun Aug 29 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 1030 PM EDT THIS EVENING FOR 
SOUTHWESTERN LAKE COUNTY...

Flood waters have receded. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 4393 8604 4393 8602 4393 8596 4387 8588
      4398 8577 4397 8571 4397 8570 4383 8585
      4389 8597 4390 8604 4391 8604 4392 8604

$$

WDM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 9:02 PM EDTSpecial Weather StatementGRRClinton58 min
Aug 28, 11:14 PM EDTSpecial Weather StatementGRRClinton61 min
Aug 29, 2:21 AM EDTAreal Flood AdvisoryGRRMason5 hr
Aug 29, 1:54 PM EDTSpecial Marine WarningGRR2 hr
Aug 29, 2:49 PM EDTSpecial Marine WarningGRR113 min
Aug 29, 3:11 PM EDTAreal Flood WarningGRRMason17 hr
Aug 29, 3:18 PM EDTSevere Thunderstorm WarningGRRMuskegon28 min
Aug 29, 3:26 PM EDTSevere Thunderstorm WarningGRRBarry, Ionia, Kent28 min
Aug 29, 4:04 PM EDTSevere Thunderstorm WarningGRRClinton, Ionia56 min
Aug 29, 5:21 PM EDTSevere Thunderstorm WarningGRRIngham24 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.