Alert archive / Iowa / Flash Flood Warnings in 2002

Flash Flood Warning 27, NWS Quad Cities, IA

August 21, 20025 counties in Iowa; Jo Daviess County, Stephenson County, Illinois

NWS Quad Cities, IA issued this flash flood warning at Aug 21, 2002, 11:34 PM CDT for 5 counties in Iowa; Jo Daviess County, Stephenson County, Illinois. It was in force for 9 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 21, 2002, 11:34 PM CDT (04:34 UTC)
Expired
Aug 22, 2002, 8:30 AM CDT
In force
9 hr
Issued by
NWS Quad Cities, IA
Area
Counties, with a storm outline in the text

Counties Buchanan County, IA, Delaware County, IA, Dubuque County, IA, Jackson County, IA, Jones County, IA, Jo Daviess County, IL, Stephenson County, IL

The radar

The Quad Cities radar (KDVN), 79 km from the middle of the area, began a volume at 04:34 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

Davenport, (KDVN), launched 00:00Z, 4.6 hours before the alert went out and 79 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, Davenport, at 00:00Z on 2002-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2239 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, Davenport, at 00:00Z on 2002-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 288 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
2239 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
997 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
288 m²/s²
0-3 km storm-relative helicity
522 m²/s²
Significant tornado parameter
4.5
Supercell composite
24.4

Open this sounding in Storm Lab

The text

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

000 
WGUS53 KDVN 220434
FFWMLI
IAC019-055-061-097-105-ILC085-177-221330-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1135 PM CDT WED AUG 21 2002

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  JACKSON COUNTY IN EAST CENTRAL IOWA
  JONES COUNTY IN EAST CENTRAL IOWA
  DUBUQUE COUNTY IN NORTHEAST IOWA
  DELAWARE COUNTY IN NORTHEAST IOWA
  BUCHANAN COUNTY IN NORTHEAST IOWA
  JO DAVIESS COUNTY IN NORTHWEST ILLINOIS
  STEPHENSON COUNTY IN NORTHWEST ILLINOIS

* UNTIL 830 AM CDT

* AT 1127 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS PRODUCING VERY HEAVY RAIN WERE LOCATED OVER THE
  WARNED AREA. 

* NATIONAL WEATHER SERVICE DOPPLER RADAR ESTIMATES INDICATE THAT 
  UP TO 4 INCHES OF RAIN HAS FALLEN OVER PORTIONS OF THE WARNED   
  AREA THIS EVENING. OVER 4 INCHES OF RAIN WAS REPORTED AT THE 
  DUBUQUE AIRPORT...AND SPOTTERS REPORTED 4.5 IN GALENA...AND 2.5 
  INCHES IN NORTHEAST JO DAVIESS COUNTY.  

  THIS RAIN...AND ADDITIONAL EXPECTED HEAVY RAINFALL CAUSED BY A
  NEARLY STATIONARY LINE OF THUNDERSTORMS...WILL CAUSE LOCAL STREAMS
  AND RIVERS TO RISE RAPIDLY AND OVERFLOW THEIR BANKS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED...
QUICKLY MOVE TO HIGHER GROUND TO ESCAPE FLOOD WATERS.

DO NOT DRIVE YOUR VEHICLE INTO WATER COVERED ROADWAYS. THE WATER MAY
BE TOO DEEP TO CROSS SAFELY OR THE ROAD COULD BE WASHED OUT. VEHICLES
CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.

LAT...LON 4248 8929 4220 8928 4223 9037 4203 9097
          4199 9125 4234 9142 4232 9180 4266 9209
          4251 9065

$$
SHEETS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 11:39 PM CDTSevere Thunderstorm WarningDVNJackson66 min
Aug 21, 10:26 PM CDTSevere Thunderstorm WarningDVNJo Daviess, Stephenson64 min

Nearby

Flash Flood Warnings in Iowa, 2002Flash Flood Warnings in Illinois, 2002Every flash flood warning in 2002

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.