Alert archive / Iowa / Flash Flood Warnings in 2012

Flash Flood Warning 10, NWS Quad Cities, IA

August 4, 2012Linn County, Iowa

NWS Quad Cities, IA issued this flash flood warning at Aug 4, 2012, 1:19 PM CDT for Linn County, Iowa. It was in force for 82 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 4, 2012, 1:19 PM CDT (18:19 UTC)
Expired
Aug 4, 2012, 2:41 PM CDT
In force
82 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Flood severity
None

County Linn County, IA

The radar

The Quad Cities radar (KDVN), 94 km from the middle of the area, began a volume at 18:19 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.

What was reported inside it

TimeReportWhereRemark
Aug 4, 1:52 PM CDTHEAVY RAIN 1.91 Sse Cedar Rapids, IASTORM TOTAL

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 6.3 hours before the alert went out and 100 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 12:00Z on 2012-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1247 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 12:00Z on 2012-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 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
1247 J/kg
Mixed-layer CIN
-144 J/kg
Mixed-layer LCL
1158 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
52 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

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

176 
WGUS53 KDVN 041819
FFWDVN
IAC113-042015-
/O.NEW.KDVN.FF.W.0010.120804T1819Z-120804T2015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
119 PM CDT SAT AUG 4 2012

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN LINN COUNTY IN EAST CENTRAL IOWA...
  THIS INCLUDES THE CITY OF CEDAR RAPIDS...

* UNTIL 315 PM CDT

* AT 111 PM CDT...EMERGENCY MANAGEMENT OFFICIALS REPORTED FLASH   
FLOODING FROM A THUNDERSTORM OVER CEDAR RAPIDS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO THE CEDAR 
RAPIDS METRO AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE ON FLOODED ROADS. MOST FATALITIES OCCUR IN VEHICLES
SWEPT AWAY IN FLOOD WATERS AS SHALLOW AS 1 FOOT.

FLOODING OF SMALL STREAMS AND CREEKS...STREETS...UNDERPASSES AND LOW
LYING URBAN AREAS IS OCCURRING.

&&

LAT...LON 4204 9174 4204 9141 4187 9140 4187 9175

$$



WOLF
1 follow-up statement
934 
WGUS73 KDVN 041941
FFSDVN

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
241 PM CDT SAT AUG 4 2012

IAC113-041950-
/O.CAN.KDVN.FF.W.0010.000000T0000Z-120804T2015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
LINN IA-
241 PM CDT SAT AUG 4 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHERN LINN
COUNTY...

LAT...LON 4204 9174 4204 9141 4187 9140 4187 9175

$$

WOLF

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 11:18 AM CDTSpecial Weather StatementDVNBenton, Buchanan, Delaware, Henry, Iowa, Jefferson and 4 more102 min
Aug 4, 12:05 PM CDTSevere Thunderstorm WarningDVNBenton, Buchanan, Delaware, Iowa, Johnson, Keokuk and 2 more55 min
Aug 4, 12:38 PM CDTSevere Thunderstorm WarningDVNCedar, Clinton, Delaware, Dubuque, Jackson, Johnson and 5 more67 min
Aug 4, 12:59 PM CDTSevere Thunderstorm WarningDVNDes Moines, Louisa, Muscatine, Scott76 min
Aug 4, 1:39 PM CDTFlash Flood WarningDVNScott70 min

Nearby

Flash Flood Warnings in Iowa, 2012Every flash flood warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.