Alert archive / Iowa / Special Weather Statements in 2020

Special Weather Statement, NWS Quad Cities, IA

March 28, 2020Louisa County, Iowa

NWS Quad Cities, IA issued this special weather statement at Mar 28, 2020, 4:21 AM CDT for Louisa County, Iowa. It was in force for 24 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
Mar 28, 2020, 4:21 AM CDT (09:21 UTC)
Expired
Mar 28, 2020, 4:45 AM CDT
In force
24 min
Issued by
NWS Quad Cities, IA

County Louisa County, IA

The radar

The Quad Cities radar (KDVN), 73 km from the middle of the area, began a volume at 09:25 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, 9.4 hours before the alert went out and 79 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 2020-03-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 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 2020-03-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 302 square meters per square second.1939587897117136Sfc1 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
4 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
610 m above ground
0-6 km bulk shear
85 kt
0-1 km storm-relative helicity
302 m²/s²
0-3 km storm-relative helicity
512 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1

Open this sounding in Storm Lab

The text

As transmitted.

557 
WWUS83 KDVN 280921
SPSDVN

Special Weather Statement
National Weather Service Quad Cities IA/IL
421 AM CDT Sat Mar 28 2020

ILC131-IAC087-115-139-183-280945-
Mercer-Henry-Louisa-Washington-Muscatine-
421 AM CDT Sat Mar 28 2020

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN MERCER...NORTHERN
HENRY...SOUTHWESTERN LOUISA...SOUTHEASTERN WASHINGTON AND SOUTH
CENTRAL MUSCATINE COUNTIES UNTIL 445 AM CDT...

At 420 AM CDT, a strong thunderstorm was located over Wyman, or 9
miles southwest of Columbus Junction, moving northeast at 50 mph.

Nickel size hail is possible with this storm.

Locations impacted include...
Muscatine, Wapello, Columbus Junction, Winfield, Fruitland, Wayland,
Grandview, Columbus City, Letts, Crawfordsville, Olds, Wyman,
Fredonia, Noble, Cairo, Virginia Grove Recreation Area, Louisa County
Fairgrounds, Swedesburg, Muscatine Municipal Airport and Flaming
Prairie Park.

Torrential rainfall is also occurring with this storm. Minor flooding
of low lying areas, creeks, streams and urban areas is possible. If
you encounter water over a roadway, do not drive through it.

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.

LAT...LON 4140 9111 4124 9101 4104 9162 4119 9171
TIME...MOT...LOC 0920Z 246DEG 45KT 4118 9149 

$$

McClure

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 27, 9:13 PM CDTRiver Flood WatchDVNDubuque61 hr
Mar 27, 11:51 PM CDTFlash Flood WarningDVNMuscatine, Scott4 hr
Mar 28, 12:35 AM CDTSpecial Weather StatementDVNIowa25 min
Mar 28, 1:05 AM CDTSpecial Weather StatementDVNIowa, Johnson40 min
Mar 28, 1:37 AM CDTSpecial Weather StatementDVNKeokuk23 min
Mar 28, 1:53 AM CDTSevere Thunderstorm WarningDVNKeokuk, Washington26 min
Mar 28, 2:29 AM CDTSpecial Weather StatementDVNClinton31 min
Mar 28, 2:44 AM CDTSpecial Weather StatementDVNCedar31 min
Mar 28, 2:55 AM CDTSevere Thunderstorm WarningDVNClinton, Jackson35 min
Mar 28, 3:57 AM CDTSpecial Weather StatementDVNJefferson33 min
Mar 28, 5:19 AM CDTSpecial Weather StatementDVNIowa26 min
Mar 28, 10:52 AM CDTRiver Flood WarningDVNDubuque, Jackson22 days
Mar 28, 10:52 AM CDTRiver Flood WarningDVNClinton, Scott24 days
Mar 28, 10:52 AM CDTRiver Flood WarningDVNLee21 days
Mar 28, 11:21 AM CDTSpecial Weather StatementDVNWashington24 min
Mar 28, 11:25 AM CDTRiver Flood WatchDVNClinton21 days
Mar 28, 11:25 AM CDTRiver Flood WatchDVNScott10 hr
Mar 28, 6:03 PM CDTSevere Thunderstorm WarningDVNBenton, Buchanan42 min
Mar 28, 6:13 PM CDTTornado Warning Tornado observedDVNBenton, Buchanan47 min
Mar 28, 6:53 PM CDTTornado WarningDVNBuchanan, Delaware28 min
Mar 27, 11:32 PM CDTSpecial Weather StatementDVNRock Island, Whiteside58 min
Mar 28, 3:21 AM CDTSpecial Weather StatementDVNCarroll24 min
Mar 28, 4:49 AM CDTSpecial Weather StatementDVNMercer26 min
Mar 28, 5:15 AM CDTSpecial Weather StatementDVNRock Island30 min
Mar 28, 10:39 AM CDTRiver Flood WatchDVNWhiteside24 hr
Mar 28, 3:42 PM CDTSpecial Weather StatementDVNRock Island33 min
Mar 28, 4:15 PM CDTSpecial Weather StatementDVNCarroll, Stephenson30 min
Mar 28, 4:48 PM CDTTornado WarningDVNWarren42 min
Mar 28, 5:29 PM CDTSevere Thunderstorm WarningDVNHenry31 min
Mar 28, 5:52 PM CDTTornado WarningDVNBureau, Henry38 min
Mar 28, 6:33 PM CDTTornado WarningDVNHenderson, Warren42 min

Nearby

Special Weather Statements in Iowa, 2020Every special weather statement in 2020

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.