Alert archive / Iowa / Special Weather Statements in 2018

Special Weather Statement, NWS Quad Cities, IA

August 6, 2018Benton County, Iowa

NWS Quad Cities, IA issued this special weather statement at Aug 6, 2018, 12:21 AM CDT for Benton County, Iowa. It was in force for 39 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
Aug 6, 2018, 12:21 AM CDT (05:21 UTC)
Expired
Aug 6, 2018, 1:00 AM CDT
In force
39 min
Issued by
NWS Quad Cities, IA

County Benton County, IA

The radar

The Quad Cities radar (KDVN), 143 km from the middle of the area, began a volume at 05:21 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, 5.4 hours before the alert went out and 148 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 2018-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1536 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 2018-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 160 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
1536 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
1707 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
160 m²/s²
0-3 km storm-relative helicity
198 m²/s²
Significant tornado parameter
0.2
Supercell composite
7.7

Open this sounding in Storm Lab

The text

As transmitted.

435 
WWUS83 KDVN 060521
SPSDVN

Special Weather Statement
National Weather Service Quad Cities IA/IL
1221 AM CDT MON AUG 6 2018

IAC011-019-060600-
Buchanan-Benton-
1221 AM CDT MON AUG 6 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN BUCHANAN AND
NORTHERN BENTON COUNTIES UNTIL 100 AM CDT...

At 1220 AM CDT, a strong thunderstorm was located near Dysart, or 16
miles south of Waterloo, moving east at 40 mph.

Wind gusts up to 50 mph and nickel size hail are possible with this
storm.

Locations impacted include...
Independence, Vinton, Urbana, Dysart, Shellsburg, Garrison, Brandon,
Mount Auburn, Lime Creek County Park, Vinton Memorial Airport,
Rodgers Park, Benton City Park, Hoefle-Dulin Park, Spencers Grove,
Minne Estema Park, Benton County Fairgrounds, Independence Airport,
Wildcat Bluff Park and Cheney.

This includes Interstate 380 between mile markers 40 and 55.
 
Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

LAT...LON 4230 9230 4230 9207 4244 9206 4246 9186
      4213 9183 4208 9184 4211 9230
TIME...MOT...LOC 0520Z 265DEG 34KT 4225 9236 

$$

Gibbs

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 7:37 PM CDTSpecial Weather StatementDVNJohnson38 min
Aug 5, 7:39 PM CDTSpecial Weather StatementDVNBuchanan, Delaware36 min
Aug 5, 9:21 PM CDTSpecial Weather StatementDVNBuchanan, Delaware39 min
Aug 5, 10:11 PM CDTSpecial Weather StatementDVNDubuque, Jackson49 min
Aug 5, 10:20 PM CDTSevere Thunderstorm WarningDVNDubuque, Jackson, Jones55 min
Aug 6, 12:38 AM CDTSpecial Weather StatementDVNBuchanan, Delaware82 min
Aug 6, 2:01 AM CDTFlash Flood WarningDVNBuchanan, Delaware5 hr
Aug 6, 5:20 AM CDTSpecial Weather StatementDVNDubuque85 min
Aug 6, 6:49 PM CDTSpecial Weather StatementDVNLee, Van Buren26 min
Aug 6, 12:01 AM CDTSpecial Weather StatementDVNStephenson29 min

Nearby

Special Weather Statements in Iowa, 2018Every special weather statement in 2018

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.