Alert archive / Iowa / Special Weather Statements in 2011

Special Weather Statement, NWS Quad Cities, IA

June 20, 2011Jefferson County, Keokuk County, Washington County, Iowa

NWS Quad Cities, IA issued this special weather statement at Jun 20, 2011, 5:14 AM CDT for Jefferson County, Keokuk County, Washington County, Iowa. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 20, 2011, 5:14 AM CDT (10:14 UTC)
Expired
Jun 20, 2011, 6:15 AM CDT
In force
61 min
Issued by
NWS Quad Cities, IA

Counties Jefferson County, IA, Keokuk County, IA, Washington County, IA

The radar

The Des Moines radar (KDMX), 136 km from the middle of the area, began a volume at 10:14 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, 10.2 hours before the alert went out and 144 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 2011-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2723 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, Davenport, at 00:00Z on 2011-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 29 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
2723 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
881 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
29 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.7
Supercell composite
6.0

Open this sounding in Storm Lab

The text

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

283 
WWUS83 KDVN 201014
SPSDVN

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
514 AM CDT MON JUN 20 2011

IAZ063-064-076-077-087-088-201115-
HENRY-IOWA-JEFFERSON-JOHNSON-KEOKUK-WASHINGTON-
514 AM CDT MON JUN 20 2011

...STRONG THUNDERSTORMS WITH GUSTY WINDS AND HEAVY RAIN...

AT 511 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 13 MILES NORTHWEST
OF WHAT CHEER TO 9 MILES WEST OF DELTA TO 16 MILES SOUTHWEST OF
HEDRICK...MOVING EAST AT 35 MPH.

* THUNDERSTORMS WILL BE NEAR...
  WHAT CHEER AND DELTA AROUND 525 AM CDT...
  MARTINSBURG...HEDRICK AND HAYESVILLE AROUND 530 AM CDT...
  SIGOURNEY AND KESWICK AROUND 535 AM CDT...
  MILLERSBURG AND BATAVIA AROUND 540 AM CDT...
  SOUTH ENGLISH AROUND 545 AM CDT...

WINDS GREATER THAN 35 MPH...FREQUENT CLOUD TO GROUND 
LIGHTNING...BRIEF HEAVY RAIN...CAN BE EXPECTED WITH THESE STORMS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 600 AM CDT MONDAY
MORNING FOR SOUTHEASTERN IOWA AND NORTHWESTERN ILLINOIS AND NORTHEAST
MISSOURI.

LAT...LON 4151 9242 4152 9230 4163 9230 4164 9172
      4095 9168 4094 9219 4115 9219 4117 9242
TIME...MOT...LOC 1013Z 269DEG 32KT 4153 9250 4128 9246
          4102 9252

$$

08

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 10:17 PM CDTFlash Flood WatchDVNDes Moines, Henry, Jefferson, Keokuk, Lee, Louisa and 2 more15 hr
Jun 19, 11:41 PM CDTSevere Thunderstorm WarningDVNLee, Van Buren49 min
Jun 20, 12:31 AM CDTSpecial Weather StatementDVNDes Moines44 min
Jun 20, 1:00 AM CDTFlash Flood WarningDVNVan Buren9 hr
Jun 20, 1:45 AM CDTSevere Thunderstorm WarningDVNHenry, Jefferson, Lee, Van Buren75 min
Jun 20, 1:51 AM CDTSpecial Weather StatementDVNIowa, Johnson, Washington39 min
Jun 20, 2:00 AM CDTSevere Thunderstorm WarningDVNDes Moines, Louisa34 min
Jun 20, 2:45 AM CDTSpecial Weather StatementDVNDes Moines, Lee75 min
Jun 20, 3:24 AM CDTSpecial Weather StatementDVNScott51 min
Jun 20, 5:52 AM CDTSpecial Weather StatementDVNCedar, Johnson, Muscatine, Washington53 min
Jun 20, 8:55 AM CDTFlash Flood WarningDVNLee4 hr
Jun 20, 9:26 AM CDTRiver Flood WarningDVNLee43 hr
Jun 20, 10:08 AM CDTAreal Flood WarningDVNVan Buren6 hr
Jun 20, 1:47 PM CDTRiver Flood WarningDVNLee, Van Buren21 hr
Jun 20, 2:55 PM CDTRiver Flood WarningDVNJohnson, Washington30 hr
Jun 20, 3:00 PM CDTRiver Flood WarningDVNKeokuk30 hr
Jun 20, 3:25 PM CDTFlash Flood WatchDVNDes Moines, Henry, Jefferson, Keokuk, Lee, Louisa and 2 more12 hr
Jun 20, 1:24 AM CDTSpecial Weather StatementDVNMercer66 min
Jun 20, 1:26 AM CDTSpecial Weather StatementDVNMercer64 min
Jun 20, 3:02 AM CDTSpecial Weather StatementDVNRock Island43 min
Jun 20, 4:26 AM CDTSpecial Weather StatementDVNBureau, Henry, Putnam94 min
Jun 20, 6:51 AM CDTRiver Flood WarningDVNHancock, McDonough4 days
Jun 20, 1:02 PM CDTAreal Flood WarningDVNClark, Scotland6 hr
Jun 20, 1:58 PM CDTRiver Flood WarningDVNClark62 hr

Nearby

Special Weather Statements in Iowa, 2011Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.