Alert archive / Michigan / Flash Flood Warnings in 1986

Flash Flood Warning 11, NWS Grand Rapids, MI

September 12, 1986Clinton County, Gratiot County, Michigan

NWS Grand Rapids, MI issued this flash flood warning at Sep 12, 1986, 2:13 AM EDT for Clinton County, Gratiot County, Michigan. It was in force for 107 min.

The area

The counties it named.

The facts

Issued
Sep 12, 1986, 2:13 AM EDT (06:13 UTC)
Expired
Sep 12, 1986, 4:00 AM EDT
In force
107 min
Issued by
NWS Grand Rapids, MI
Area
Whole counties

Counties Clinton County, MI, Gratiot County, MI

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Detroit, MI (KFNT), launched 00:00Z, 6.2 hours before the alert went out and 105 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 00:00Z on 1986-09-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 00:00Z on 1986-09-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 square meters per square second.1939587897Sfc1 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
1 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
900 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
78 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KLAN 120613
FFWLAN
MIC057-037-120800-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LANSING MI
213 AM EDT FRI SEP 12 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 400 AM EDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

CENTRAL LOWER MICHIGAN...GRATIOT AND CLINTON


AT 200 AM EDT THE DAM ON RAINBOW LAKE WAS CRUMBLING AND COMPLETE
COLLAPSE IS CONSIDERED IMMINENT. THOSE NEAR PINE CREEK AND THE
MAPLE RIVER IN GRATIOT AND CLINTON COUNTIES ARE URGED TO SEEK THE
SAFETY OF HIGH GROUND UNTIL THE DANGER OF RISING WATER PASSES.

A FLASH FLOOD WARNING MEANS FLOODING IS IMMINENT OR HAS BEEN
REPORTED. DO NOT ATTEMPT TO CROSS WATER OF UNKNOWN DEPTH OR FAST
MOVING CURRENTS. REMEMBER...MOST FATALITIES IN FLASH FLOODS OCCUR IN
AUTOMOBILES.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 12, 2:05 AM EDTFlash Flood WarningGRRIonia4 hr
Sep 12, 2:54 AM EDTFlash Flood WarningGRRKent66 min
Sep 12, 4:18 AM EDTFlash Flood WarningGRRClinton, Gratiot2 hr
Sep 12, 7:00 AM EDTFlash Flood WarningGRRClinton, Gratiot2 hr
Sep 12, 7:29 PM EDTFlash Flood WarningGRRIonia, Kent4 hr

Nearby

Flash Flood Warnings in Michigan, 1986Every flash flood warning in 1986

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.