Alert archive / Iowa / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 61, NWS Quad Cities, IA

July 28, 2021Buchanan County, Delaware County, Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Jul 28, 2021, 12:50 AM CDT for Buchanan County, Delaware County, Iowa. It was in force for 40 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
Jul 28, 2021, 12:50 AM CDT (05:50 UTC)
Expired
Jul 28, 2021, 1:30 AM CDT
In force
40 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Buchanan County, IA, Delaware County, IA

The radar

The Quad Cities radar (KDVN), 126 km from the middle of the area, began a volume at 05:54 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 watch it was issued in

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

IssuedProductOfficeLasted
Jul 27, 8:03 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 5.8 hours before the alert went out and 129 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 2021-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1554 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 2021-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 68 square meters per square second.19395878Sfc1 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
1554 J/kg
Mixed-layer CIN
-284 J/kg
Mixed-layer LCL
1342 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

377 
WUUS53 KDVN 280550
SVRDVN
IAC019-055-280630-
/O.NEW.KDVN.SV.W.0061.210728T0550Z-210728T0630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
1250 AM CDT Wed Jul 28 2021

The National Weather Service in the Quad Cities has issued a

* Severe Thunderstorm Warning for...
  Eastern Buchanan County in northeastern Iowa...
  Delaware County in northeastern Iowa...

* Until 130 AM CDT.

* At 1249 AM CDT, a severe thunderstorm was located near Aurora, or
  11 miles northeast of Independence, moving southeast at 45 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Dundee and Masonville around 100 AM CDT.
  Manchester around 105 AM CDT.

Other locations in the path of this severe thunderstorm include
Delhi, Ryan, Delaware and Hopkinton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4264 9148 4236 9113 4230 9113 4230 9170
      4259 9194 4264 9187
TIME...MOT...LOC 0549Z 311DEG 41KT 4257 9172 

HAIL...1.00IN
WIND...60MPH
 
$$

RP Kinney
2 follow-up statements
056 
WWUS53 KDVN 280614
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
114 AM CDT Wed Jul 28 2021

IAC019-055-280630-
/O.CON.KDVN.SV.W.0061.000000T0000Z-210728T0630Z/
Buchanan IA-Delaware IA-
114 AM CDT Wed Jul 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 AM CDT
FOR SOUTHEASTERN BUCHANAN AND DELAWARE COUNTIES...

At 113 AM CDT, a severe thunderstorm was located over Masonville, or
near Manchester, moving southeast at 40 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Public.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
  Manchester, Delhi, Ryan, Delaware and Hopkinton.

At 1250 am CST, a public weather station just north of Aurora 
reported a wind gust of 63 mph.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
sturdy building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4263 9148 4236 9113 4230 9113 4230 9170
      4251 9184
TIME...MOT...LOC 0613Z 309DEG 34KT 4249 9157 

HAIL...0.75IN
WIND...60MPH
 
$$

RP Kinney
829 
WWUS53 KDVN 280626
SVSDVN

Severe Weather Statement
National Weather Service Quad Cities IA/IL
126 AM CDT Wed Jul 28 2021

IAC019-055-280635-
/O.EXP.KDVN.SV.W.0061.000000T0000Z-210728T0630Z/
Buchanan IA-Delaware IA-
126 AM CDT Wed Jul 28 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BUCHANAN AND
DELAWARE COUNTIES WILL EXPIRE AT 130 AM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However small 
hail and gusty winds to 40 mph are still possible from Quasqueton, 
to Robinson and Ryan through 2 am.

A Severe Thunderstorm Watch remains in effect until 200 AM CDT for
northeastern Iowa.

LAT...LON 4263 9148 4236 9113 4230 9113 4230 9170
      4251 9184
TIME...MOT...LOC 0625Z 316DEG 40KT 4236 9155 

$$

RP Kinney

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 28, 12:28 AM CDTSpecial Weather StatementDVNBuchanan47 min
Jul 28, 1:29 AM CDTSpecial Weather StatementDVNLinn31 min
Jul 28, 1:52 AM CDTSpecial Weather StatementDVNDubuque38 min
Jul 28, 2:37 AM CDTSpecial Weather StatementDVNJackson38 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2021Every severe thunderstorm warning in 2021

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.