Alert archive / Iowa / Flash Flood Warnings in 1987

Flash Flood Warning 1, NWS Quad Cities, IA

August 21, 1987Scott County, Iowa; Rock Island County, Illinois

NWS Quad Cities, IA issued this flash flood warning at Aug 21, 1987, 5:53 AM CDT for Scott County, Iowa; Rock Island County, Illinois. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Aug 21, 1987, 5:53 AM CDT (10:53 UTC)
Expired
Aug 21, 1987, 8:35 AM CDT
In force
3 hr
Issued by
NWS Quad Cities, IA
Area
Whole counties

Counties Scott County, IA, Rock Island County, IL

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

Peoria Regional, IL (KPIA), launched 00:00Z, 10.9 hours before the alert went out and 129 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, Peoria Regional, IL at 00:00Z on 1987-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1095 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, Peoria Regional, IL at 00:00Z on 1987-08-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 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
1095 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
1543 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
231 m²/s²
Significant tornado parameter
0.4
Supercell composite
6.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMLI 211053
FFWMLI
IAC163-ILC161-211500-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOLINE IL
553 AM CDT FRI AUG 21 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 1000 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

EXTREME EAST IOWA...SCOTT
NORTHWEST ILLINOIS...ROCK-ISLAND

AT 540 AM CDT FLOODING WAS REPORTED IN THE QUAD CITY METRO AREA.
SOME STREETS WERE UNDER 2 TO 4 FEET OF WATER IN DAVENPORT IA AND
IN EAST MOLINE IL.

HEAVY RAINFALL WILL CONTINUE TILL 630 AM CDT...CAUSING FURTHER
RISES ON SMALL STREAMS AND URBAN FLOODING.

FLASH FLOOD WARNING MEANS FLASH FLOODING IS OCCURRING OR IS
IMMINENT IN THE SPECIFIED AREA.

PERSONS ALONG OR NEAR STREAMS SUBJECT TO FLASH FLOODING OR SHARP
RISES SHOULD BE PREPARED TO MOVE TO A PLACE OF SAFETY IMMEDIATELY.

DO NOT TRY TO DRIVE THROUGH FLOODED AREAS...ESPECIALLY FLOWING WATER.

IF TIME PERMITS...ASK THE NEAREST LAW ENFORECMENT AGENCY TO RELAY
YOUR REPORT OF FLOODING TO THE NATIONAL WEATHER SERVICE.

ATTN ISP 7 AND 1

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 21, 12:32 AM CDTSevere Thunderstorm WarningDVNJones43 min
Aug 21, 12:39 AM CDTSevere Thunderstorm WarningDVNCedar21 min
Aug 21, 1:02 AM CDTSevere Thunderstorm WarningDVNCedar, Muscatine38 min
Aug 21, 1:49 AM CDTSevere Thunderstorm WarningDVNScott26 min
Aug 21, 2:18 AM CDTSevere Thunderstorm WarningDVNScott42 min
Aug 21, 3:31 AM CDTSevere Thunderstorm WarningDVNScott29 min
Aug 21, 4:01 AM CDTSevere Thunderstorm WarningDVNScott59 min
Aug 21, 4:57 AM CDTSevere Thunderstorm WarningDVNCedar, Clinton, Scott33 min
Aug 21, 5:28 AM CDTSevere Thunderstorm WarningDVNScott47 min
Aug 21, 2:18 AM CDTSevere Thunderstorm WarningDVNHenry, Mercer, Rock Island42 min
Aug 21, 4:01 AM CDTSevere Thunderstorm WarningDVNMercer59 min
Aug 21, 4:57 AM CDTSevere Thunderstorm WarningDVNHenry33 min

Nearby

Flash Flood Warnings in Iowa, 1987Flash Flood Warnings in Illinois, 1987Every flash flood warning in 1987

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.