Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 72, NWS Quad Cities, IA

August 4, 20128 counties in Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 4, 2012, 12:05 PM CDT for 8 counties in Iowa. It was in force for 55 min. 18 reports 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, 12:05 PM CDT (17:05 UTC)
Expired
Aug 4, 2012, 1:00 PM CDT
In force
55 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Benton County, IA, Buchanan County, IA, Delaware County, IA, Iowa County, IA, Johnson County, IA, Keokuk County, IA, Linn County, IA, Washington County, IA

The radar

The Quad Cities radar (KDVN), 112 km from the middle of the area, began a volume at 17:05 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, 12:25 PM CDTTSTM WND DMGFrytown, IATREES DOWN AND WINDOWS BLOWN OUT OF A RESIDENCE. A GRAIN BIN IS ALSO REPORTED DOWN. DELAYED REPORT.
Aug 4, 12:25 PM CDTTSTM WND GST 65W Norway, IASPOTTER ESTIMATED SUSTAINED 40 GUST 60-70 MPH.
Aug 4, 12:28 PM CDTTSTM WND GST 65W Norway, IAWINDS ESTIMATED AT 60 TO 65 MPH WITH HEAVY RAIN WITH VISIBILITY OF A QUARTER OF A MILE OR LESS.
Aug 4, 12:35 PM CDTTSTM WND DMG5 Nw Iowa City, IA3 INCH DIAMETER TREE BRANCH DOWN ON HOME. NUMEROUS SMALLER BRANCHES DOWN.
Aug 4, 12:35 PM CDTTSTM WND GST 605 Nw Iowa City, IA
Aug 4, 12:36 PM CDTTSTM WND GST 603 Wnw Iowa City, IAA TRAINED SPOTTER REPORTED ESTIMATED WIND GUSTS OF 50 TO 60 MPH.
Aug 4, 12:38 PM CDTTSTM WND GST 72Cedar Rapids Municipal, IAMEASURED FROM ASOS.
Aug 4, 12:38 PM CDTTSTM WND GST 72Cedar Rapids Municipal, IA
Aug 4, 12:40 PM CDTTSTM WND GST 601 Sse Cedar Rapids, IAA TRAINED SPOTTER ESTIMATED WINDS OF 50 TO 60 MPH.
Aug 4, 12:47 PM CDTTSTM WND GST 601 Sse Cedar Rapids, IA
Aug 4, 12:47 PM CDTTSTM WND GST 655 Nne Cedar Rapids, IAA TRAINED SPOTTER ESTIMATED THUNDERSTORM WINDS OF 06 TO 65 MPH.
Aug 4, 12:47 PM CDTTSTM WND GST 73Cedar Rapids Municipal, IA
Aug 4, 12:47 PM CDTTSTM WND GST 751 Sse Cedar Rapids, IAA TRAINED SPOTTER ESTIMATED WINDS OF 70 TO 75 MPH.
Aug 4, 12:48 PM CDTTSTM WND DMG1 Sw Cedar Rapids, IAA TRAINED SPOTTER REPORTED 3 TO 4 INCH DIAMETER TREE LIMBS DOWN. ESTIMATED WIND GUSTS OF 70 TO 75 MPH.
Aug 4, 12:48 PM CDTTSTM WND DMG2 Nnw North Liberty, IAALUMINUM FLAG POLE SNAPPED AND SEVERAL TREES DAMAGED.
Aug 4, 12:48 PM CDTTSTM WND GST 652 Nnw North Liberty, IAESTIMATED 60 TO 65 MPH.
Aug 4, 12:48 PM CDTTSTM WND GST 70Ely, IAESTIMATED WINDS OF 60 TO 70 MPH. HEAVY RAIN IS REDUCING VISIBILITY.
Aug 4, 12:55 PM CDTTSTM WND DMG1 Sse Cedar Rapids, IASPOTTER REPORT OF 12 INCH TREE TOWN. REPORT WAS DELAYED.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 4, 10:50 AM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 5.1 hours before the alert went out and 119 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.

483 
WUUS53 KDVN 041705
SVRDVN
IAC011-019-055-095-103-107-113-183-041800-
/O.NEW.KDVN.SV.W.0072.120804T1705Z-120804T1800Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1205 PM CDT SAT AUG 4 2012

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BENTON COUNTY IN EAST CENTRAL IOWA...
  IOWA COUNTY IN EAST CENTRAL IOWA...
  JOHNSON COUNTY IN EAST CENTRAL IOWA...
  LINN COUNTY IN EAST CENTRAL IOWA...
  SOUTHERN BUCHANAN COUNTY IN NORTHEAST IOWA...
  SOUTHWESTERN DELAWARE COUNTY IN NORTHEAST IOWA...
  KEOKUK COUNTY IN SOUTHEAST IOWA...
  WASHINGTON COUNTY IN SOUTHEAST IOWA...

* UNTIL 100 PM CDT.

* AT 1201 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS
  AROUND 60 MPH.  THESE STORMS WERE LOCATED APPROXIMATELY ALONG A
  LINE EXTENDING FROM 10 MILES WEST OF MOUNT AUBURN TO RICHLAND...OR
  ALONG A LINE EXTENDING FROM 15 MILES SOUTH OF WATERLOO TO 15 MILES
  NORTH OF FAIRFIELD...AND MOVING EAST AT 30 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  KINROSS...PARNELL...MARENGO...WILLIAMSBURG...BLAIRSTOWN...
  GARRISON...VAN HORNE...CONROY...BRIGHTON...WELLMAN...VINTON...
  COPPOCK...NEWHALL...NORWAY...AMANA...WASHINGTON...WALFORD...
  OXFORD...RICHMOND...KALONA...ATKINS...SHELLSBURG...FAIRFAX...
  URBANA...CRAWFORDSVILLE...PALO...AINSWORTH...TIFFIN...SWISHER...
  RIVERSIDE...CENTER POINT...WALKER...CORALVILLE...SHUEYVILLE...
  OAKDALE...NORTH LIBERTY...TODDVILLE...CEDAR RAPIDS...HIAWATHA...
  HILLS...UNIVERSITY HEIGHTS...ROBINS...IOWA CITY...ELY...LAKE
  MACBRIDE STATE PARK...SOLON...LONE TREE...WHITTIER...WAUBEEK...
  VIOLA...TROY MILLS...SPRINGVILLE...PRAIRIEBURG...PARIS...MOUNT
  VERNON...MARION...LISBON...COGGON...CENTRAL CITY...BERTRAM AND
  ALBURNETT.

THIS INCLUDES INTERSTATE 80 IN IOWA BETWEEN MILE MARKERS 205 AND 253.

THIS INCLUDES INTERSTATE 380 BETWEEN MILE MARKERS 1 AND 49.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. MOVE IMMEDIATELY INDOORS AND STAY AWAY
FROM WINDOWS.

&&

LAT...LON 4151 9238 4152 9230 4230 9230 4230 9135
      4230 9136 4142 9137 4142 9148 4116 9149
      4117 9241
TIME...MOT...LOC 1705Z 276DEG 28KT 4228 9225 4122 9191
WIND...HAIL 60MPH <1.00IN

$$

NICHOLS
2 follow-up statements
773 
WWUS53 KDVN 041721
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1221 PM CDT SAT AUG 4 2012

IAC107-041730-
/O.CAN.KDVN.SV.W.0072.000000T0000Z-120804T1800Z/
KEOKUK IA-
1221 PM CDT SAT AUG 4 2012

...THE SEVERE THUNDERSTORM WARNING FOR KEOKUK COUNTY IS CANCELLED...

THE THUNDERSTORM THAT WAS CAPABLE OF PRODUCING SEVERE WEATHER HAS 
MOVED OUT OF THE WARNED AREA. THEREFORE THE SEVERE THUNDERSTORM 
WARNING HAS BEEN CANCELLED.

HOWEVER...THIS STORM IS STILL CAPABLE OF PRODUCING GUSTY WINDS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 500 PM CDT
SATURDAY AFTERNOON FOR EASTERN IOWA AND NORTHWESTERN ILLINOIS.

LAT...LON 4230 9136 4142 9137 4142 9148 4116 9149
      4116 9188 4182 9198 4230 9229
TIME...MOT...LOC 1720Z 276DEG 28KT 4227 9209 4121 9176

$$

IAC011-019-095-103-113-183-041800-
/O.CON.KDVN.SV.W.0072.000000T0000Z-120804T1800Z/
WASHINGTON IA-LINN IA-JOHNSON IA-IOWA IA-BENTON IA-BUCHANAN IA-
1221 PM CDT SAT AUG 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 100 PM CDT
FOR SOUTHERN BUCHANAN...BENTON...EASTERN IOWA...JOHNSON...LINN AND
WASHINGTON COUNTIES...

AT 1219 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS AROUND 60 MPH.  THESE STORMS WERE LOCATED APPROXIMATELY ALONG A
LINE EXTENDING FROM MOUNT AUBURN TO BRIGHTON...OR ALONG A LINE
EXTENDING FROM 8 MILES NORTHWEST OF VINTON TO 8 MILES SOUTHWEST OF
WASHINGTON...MOVING EAST AT 30 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
NEWHALL...COPPOCK...VINTON MEMORIAL AIRPORT...MIDDLE AMANA...
NORWAY...HOMESTEAD...AMANA...AMISH...EAST AMANA...WASHINGTON
AIRPORT...WINDHAM...WALFORD...OXFORD...RICHMOND...FRYTOWN...NOBLE...
ATKINS...KALONA...CHENEY...COSGROVE...SHELLSBURG...KENT COUNTY
PARK...URBANA...FAIRFAX...SHARON CENTER...SPENCERS GROVE...
CRAWFORDSVILLE...PALO...AINSWORTH...TIFFIN...CEDAR RAPIDS MUNICIPAL
AIRPORT...SWISHER...HASKINS...RIVERSIDE...COU FALLS...CENTER POINT...
WALKER...CORALVILLE...SHUEYVILLE...OAKDALE...NORTH LIBERTY...
TODDVILLE...CEDAR RAPIDS...HIAWATHA...HILLS...UNIVERSITY HEIGHTS...
MIDWAY...IOWA CITY MUNICIPAL AIRPORT...RIVER JUNCTION...SANDY BEACH
CAMP GROUND...ROBINS...UNIVERSITY OF IOWA...IOWA CITY...LAFAYETTE...
SUGAR BOTTOM CAMP GROUND...TWIN VIEW HEIGHTS...ELY...TROY MILLS...
LAKE MACBRIDE STATE PARK...WEST OVERLOOK...NEWPORT...SUTLIFF...
SOLON...OASIS...MORSE...LONE TREE...ELMIRA...WHITTIER...WAUBEEK...
VIOLA...SPRINGVILLE...PRAIRIEBURG...PARIS...PARALTA...
PALISADES-KEPLER SATE PARK...MOUNT VERNON...MARION AIRPORT...
MARION...LISBON...COGGON...CENTRAL CITY...BERTRAM AND ALBURNETT.

THIS INCLUDES INTERSTATE 80 IN IOWA BETWEEN MILE MARKERS 223 AND 253.

THIS INCLUDES INTERSTATE 380 BETWEEN MILE MARKERS 1 AND 49.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 500 PM CDT
SATURDAY AFTERNOON FOR EASTERN IOWA AND NORTHWESTERN ILLINOIS.

&&

LAT...LON 4230 9136 4142 9137 4142 9148 4116 9149
      4116 9188 4182 9198 4230 9229
TIME...MOT...LOC 1720Z 276DEG 28KT 4227 9209 4121 9176
WIND...HAIL 60MPH <1.00IN

$$
200 
WWUS53 KDVN 041800
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
100 PM CDT SAT AUG 4 2012

IAC011-019-095-103-113-183-041811-
/O.EXP.KDVN.SV.W.0072.000000T0000Z-120804T1800Z/
WASHINGTON IA-LINN IA-JOHNSON IA-IOWA IA-BENTON IA-BUCHANAN IA-
100 PM CDT SAT AUG 4 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN BUCHANAN...
NORTHEASTERN BENTON...EASTERN IOWA...JOHNSON...LINN AND WASHINGTON
COUNTIES HAS EXPIRED...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 500 PM CDT
SATURDAY AFTERNOON FOR EASTERN IOWA AND NORTHWESTERN ILLINOIS.

LAT...LON 4230 9136 4142 9137 4142 9148 4116 9149
      4116 9188 4182 9198 4230 9229
TIME...MOT...LOC 1721Z 276DEG 28KT 4227 9208 4121 9175

$$

NICHOLS

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, 12:38 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, 1:19 PM CDTFlash Flood WarningDVNLinn82 min
Aug 4, 1:39 PM CDTFlash Flood WarningDVNScott70 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2012Every severe thunderstorm 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.