Alert archive / Iowa / Tornado Warnings in 2011

Tornado Warning 15, NWS Quad Cities, IA

July 27, 2011Dubuque County, Jackson County, Iowa

NWS Quad Cities, IA issued this tornado warning at Jul 27, 2011, 8:29 PM CDT for Dubuque County, Jackson County, Iowa. It was in force for 46 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
Jul 27, 2011, 8:29 PM CDT (01:29 UTC)
Expired
Jul 27, 2011, 9:15 PM CDT
In force
46 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon

Counties Dubuque County, IA, Jackson County, IA

The radar

The Quad Cities radar (KDVN), 74 km from the middle of the area, began a volume at 01:32 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
Jul 27, 9:12 PM CDTFUNNEL CLOUD1 N Springbrook, IARELAYED BY JACKSON EMERGENCY MANAGER.

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
Jul 27, 7:43 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.5 hours before the alert went out and 73 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 2011-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4556 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 2011-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 141 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
4556 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
962 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
141 m²/s²
0-3 km storm-relative helicity
316 m²/s²
Significant tornado parameter
3.9
Supercell composite
19.4

Open this sounding in Storm Lab

The text

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

727 
WFUS53 KDVN 280129
TORDVN
IAC061-097-280215-
/O.NEW.KDVN.TO.W.0015.110728T0129Z-110728T0215Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
829 PM CDT WED JUL 27 2011

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  JACKSON COUNTY IN EAST CENTRAL IOWA...
  SOUTHEASTERN DUBUQUE COUNTY IN NORTHEAST IOWA...

* UNTIL 915 PM CDT.

* AT 823 PM CDT...TRAINED SPOTTERS AND DOPPLER RADAR INDICATED A   
  FUNNEL OR WALL CLOUD WITH A POSSIBLE TORNADO NEAR ZWINGLE ...OR 
  14 MILES SOUTH OF DUBUQUE...  MOVING EAST AT 20 MPH.

* THE TORNADO WILL BE NEAR...
  ZWINGLE AND OTTER CREEK THROUGH 840 PM CDT...
  LA MOTTE AROUND 850 PM CDT...
  COTTONVILLE AROUND 855 PM CDT...
  BELLEVUE...SPRINGBROOK AND SMITHS AROUND 915 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE IN A TORNADO IS IN A BASEMENT OR INTERIOR ROOM
OR HALLWAY ON THE LOWEST FLOOR OF A BUILDING.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

&&

LAT...LON 4236 9045 4233 9042 4228 9043 4226 9042
      4222 9038 4220 9033 4209 9038 4223 9084
      4229 9086 4237 9082
TIME...MOT...LOC 0128Z 287DEG 16KT 4231 9074

$$

LE
1 follow-up statement
014 
WWUS53 KDVN 280144
SVSDVN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
844 PM CDT WED JUL 27 2011

IAC061-280153-
/O.CAN.KDVN.TO.W.0015.000000T0000Z-110728T0215Z/
DUBUQUE IA-
844 PM CDT WED JUL 27 2011

...THE TORNADO WARNING FOR SOUTHEASTERN DUBUQUE COUNTY IS
CANCELLED...

THE THUNDERSTORM THAT WAS CAPABLE OF PRODUCING A TORNADO HAS MOVED 
SOUTHEAST OUT OF THE WARNED AREA. THEREFORE THE TORNADO WARNING HAS 
BEEN CANCELLED.

HOWEVER...THIS STORM IS STILL CAPABLE OF PRODUCING VERY HEAVY 
RAINFALL.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

LAT...LON 4236 9045 4233 9042 4228 9043 4225 9042
      4222 9038 4220 9033 4209 9038 4219 9071
      4228 9067 4237 9066
TIME...MOT...LOC 0143Z 287DEG 16KT 4229 9065

$$

IAC097-280215-
/O.CON.KDVN.TO.W.0015.000000T0000Z-110728T0215Z/
JACKSON IA-
844 PM CDT WED JUL 27 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 915 PM CDT FOR EASTERN
JACKSON COUNTY...

AT 840 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A POSSIBLE TORNADO.  THIS TORNADO WAS LOCATED APPROXIMATELY 
NEAR LA MOTTE...OR 15 MILES SOUTH OF DUBUQUE...MOVING EAST AT 20 MPH.

THE TORNADO WILL BE NEAR...
  COTTONVILLE AROUND 855 PM CDT...
  BELLEVUE...SMITHS AND SPRINGBROOK AROUND 915 PM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM CDT THURSDAY MORNING
FOR NORTHEASTERN IOWA AND NORTHWEST ILLINOIS.

&&

LAT...LON 4236 9045 4233 9042 4228 9043 4225 9042
      4222 9038 4220 9033 4209 9038 4219 9071
      4228 9067 4237 9066
TIME...MOT...LOC 0143Z 287DEG 16KT 4229 9065

$$

LE

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 7:10 PM CDTFlash Flood WarningDVNDubuque, Jackson9 hr
Jul 27, 7:35 PM CDTTornado WarningDVNDubuque, Jackson40 min
Jul 27, 9:16 PM CDTTornado WarningDVNJackson31 min
Jul 27, 11:55 PM CDTFlash Flood WarningDVNJackson4 hr
Jul 28, 12:50 AM CDTSpecial Weather StatementDVNDelaware, Dubuque, Jackson55 min
Jul 28, 1:13 AM CDTFlash Flood WarningDVNBuchanan, Delaware5 hr
Jul 28, 4:10 AM CDTAreal Flood WarningDVNDelaware, Dubuque, Jackson, Jones12 hr
Jul 28, 9:26 AM CDTSpecial Weather StatementDVNBenton, Buchanan, Delaware, Linn64 min
Jul 28, 9:40 AM CDTSpecial Weather StatementDVNMuscatine, Scott50 min
Jul 28, 10:15 AM CDTRiver Flood WarningDVNDubuque, Jackson6 hr
Jul 28, 10:15 AM CDTRiver Flood WarningDVNJackson6 hr
Jul 28, 12:03 PM CDTHeat AdvisoryDVNDes Moines, Henry, Jefferson, Keokuk, Lee, Louisa and 2 more10 hr

Nearby

Tornado Warnings in Iowa, 2011Every tornado warning in 2011Tornadoes in 2011

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.