Alert archive / Illinois / Flash Flood Warnings in 1986

Flash Flood Warning 4, NWS Quad Cities, IA

July 8, 1986Rock Island County, Whiteside County, Illinois

NWS Quad Cities, IA issued this flash flood warning at Jul 8, 1986, 8:51 PM CDT for Rock Island County, Whiteside County, Illinois. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued
Jul 8, 1986, 8:51 PM CDT (01:51 UTC)
Expired
Jul 9, 1986, 12:00 AM CDT
In force
3 hr
Issued by
NWS Quad Cities, IA
Area
Whole counties

Counties Rock Island County, IL, Whiteside 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, 1.9 hours before the alert went out and 118 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 1986-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1445 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 1986-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 129 square meters per square second.193958Sfc1 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
1445 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1379 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
129 m²/s²
0-3 km storm-relative helicity
208 m²/s²
Significant tornado parameter
0.3
Supercell composite
7.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMLI 090151
FFWMLI
IAC163-045-031-ILC161-195-090500-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOLINE IL
851 PM CDT TUE JUL 8 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A FLASH FLOOD WARNING 
EFFECTIVE UNTIL 1200 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

EXTREME EAST IOWA...SCOTT...CLINTON AND CEDAR
NORTHWEST ILLINOIS...NORTHERN ROCK-ISLAND AND WHITESIDE

A CONTINUING OUTBREAK OF STRONG THUNDERSTORMS HAS PRODUCED
RAINFALL AMOUNTS OF MORE THAN TWO INCHES IN A SHORT TIME
OVER PARTS OF THESE COUNTIES.  MANY PLACES WERE STILL
RAINING AND MORE IS EXPECTED.

THERE HAVE BEEN NUMEROUS REPORTS OF SMALL STREAMS OUT OF
THEIR BANKS IN THOSE COUNTIES.

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

 DO NOT TRY TO DRIVE THROUGH FLOODED AREAS.

 PERSONS ALONG OR NEAR STREAMS SUBJECT TO FLASH FLOODING SHOULD
 BE PREPARED TO MOVE TO A PLACE OF SAFETY IM`MEDIATELY.

WIGGINS

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jul 8, 5:45 PM CDT, 3 hours 6 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DUBUQUE IA
545 PM CDT TUE JUL 8 1986

...INTENSE THUNDERSTORMS MOVING THROUGH JONES COUNTY IN EASTCENTRAL
   IOWA...

AT 540 PM THUNDERSTORMS CONTINUED TO STRENGTHEN AS THEY MOVED EAST
THOUGH JONES COUNTY IN NORTHEAST IOWA.

LOCATION OF THE STRONGEST STORMS WERE IN THE SOUTHERN PART OF JONES
COUNTY..10 MILES SOUTH AND EAST OF ANAMOSA..45 MILES SOUTHWEST OF
DUBUQUE.  MOVEMENT WAS EAST AT 30 MILES AN HOUR.

THESE STORMS MAY PRODUCE STRONG WIND..HEAVY RAIN AND POSSIBLE PEA TO
MARBLE SIZE HAIL AS THEY MOVE THROUGH.

PERSONS IN JONES COUNTY SHOULD BE ALERT FOR THESE INTENSE STORMS AND
IF THREATENING WEATHER IS SIGHTED..TAKE COVER IMMEDIOATELY.

KOWALSKI
Special weather statement, Jul 8, 6:20 PM CDT, 2 hours 31 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOLINE IL
620 PM CDT TUE JUL 8 1986

...HEAVY RAINFALL AND STRONG THUNDERSTORMS MOVING ACROSS EASTERN
IOWA AND INTO NORTHWESTERN ILLINOIS...

AT 615 PM..RADAR SHOWED A 25 MILE WIDE BAND OF SHOWERS AND STRONG
THUNDERSTORMS EXTENDING FROM NORTH OF CEDAR RAPIDS TO NORTH OF
OF CLINTON..BOTH IN IOWA TO SOUTH OF STERLING ILLINOIS.

SOME OF THESE STORMS ARE CHARACTERIZED BY VERY HEAVY DOWNPOURS..
SMALL HAIL AND STRONG WINDS.  THIS COUPLED WITH THE SLOW MOVEMENT
OF THE STORMS WILL CAUSE SOME SMALL STREAM AND URBAN FLOODING IN
SOUTHERN CEDAR..NORTHERN CLINTON AND SOUTHERN JACKSON COUNTIES
IN EASTERN IOWA AND SOUTHERN WHITESIDE COUNTY IN NORTHWESTERN
ILLINOIS.

PERSONS ALONG STREAMS SUBJECT TO RAPID RISES SHOULD BE PREPARED TO
MOVE TO HIGHER GROUND./WIGGINS
Special weather statement, Jul 8, 7:54 PM CDT, 57 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOLINE IL
755 PM CDT TUE JUL 8 1986

AT 750 PM..RADAR SHOWED A CLUSTER OF STRONG THUNDERSTORMS ALONG
THE WAPSI RIVER BETWEEN CLINTON AND SCOTT COUNTIES IN EASTERN
IOWA.

THERE HAVE BEEN NUMEROUS REPORTS OF STRONG WINDS RESULTING IN
SOME TREES AND POWER LINES DOWN.  HEAVY DOWNPOURS WERE ALSO
OCCURRING AND PRODUCING SMALL STREAM..LOWLAND AND URBAN
FLOODING.

PERSONS ALONG STREAMS SUBJECT TO RAPID; RISES SHOULD BE PREPARED
TO MOVE TO A SAFE PLACE.

WIGGINS
Special weather statement, Jul 8, 8:07 PM CDT, 44 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DUBUQUE IA
805 PM CDT TUE JUL 8 1986

...HEAVY THUNDERSTORMS MOVING ACROSS EASTERN IOWA...

AT 800 PM HEAVY THUNDERSTORMS WERE MOVING ACROSS SOUTHERN PORTIONS OF
JONES AND JACKSON COUNTIES OF EASTCENTRAL IOWA.  THE STRONGEST OF
THESE STORMS WERE ALONG AN EAST - WEST LINE FROM 30 MILES SOUTHWEST
OF DUBUQUE TO 35 MILES SOUTHEAST OF DUBUQUE.  OTHER HEAVY THUNDER-
STORMS WILL BE MOVNING ACROSS SOUTHERN PORTIONS OF DUBUQUE COUNTY.

THESE STORMS HAVE PRODUCED IN EXCESS OF TWO INCHES OF RAIN IN A 2
HOUR PERIOD.  SMALL STREAM AND ROADWAY FLOODING CAN BE EXPECTED AS
THESE STORMS MOVE TO THE SOUTHEAST AT 35 MILES AND HOUR.

PERSONS IN JONES AND JACKSON AND DUBUQUE COUNTIES OF EASTERN IOWA
SHOULD BE ALERT FOR THESE INTENSE STORMS AND IF THREATENING WEATHER
IS SIGHTED..TAKE COVER IMMEDIATELY.

ASMUS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 7:10 PM CDTSevere Thunderstorm WarningDVNWhiteside20 min
Jul 8, 8:29 PM CDTSevere Thunderstorm WarningDVNWhiteside31 min
Jul 8, 9:20 PM CDTSevere Thunderstorm WarningDVNRock Island40 min

Nearby

Flash Flood Warnings in Illinois, 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.