Alert archive / Iowa / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 5, NWS Des Moines, IA

April 19, 2000Black Hawk County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Apr 19, 2000, 8:26 PM CDT for Black Hawk County, Iowa. It was in force for 29 min. 2 reports came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
Apr 19, 2000, 8:26 PM CDT (01:26 UTC)
Expired
Apr 19, 2000, 8:55 PM CDT
In force
29 min
Issued by
NWS Des Moines, IA
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Black Hawk County, IA

What was reported inside it

TimeReportWhereRemark
Apr 19, 8:35 PM CDTHail 1.5La Porte City, IA
Apr 19, 8:40 PM CDTHail 2.5La Porte City, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.4 hours before the alert went out and 160 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 2000-04-20Temperature 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 2000-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 471 square meters per square second.1939587897Sfc1 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
-616 J/kg
Mixed-layer LCL
865 m above ground
0-6 km bulk shear
66 kt
0-1 km storm-relative helicity
471 m²/s²
0-3 km storm-relative helicity
491 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KDMX 200127
SVRDSM
IAC013-200200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
826 PM CDT WED APR 19 2000

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN BLACK HAWK COUNTY IN NORTHEAST IOWA

* UNTIL 855 PM CDT

* AT 826 PM CDT DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM WITH
  LARGE HAIL 12 MILES SOUTHWEST OF LA PORTE CITY...OR ABOUT 23 MILES
  SOUTH OF WATERLOO...MOVING NORTHEAST AT 40 MPH.

* THE SEVERE THUNDERSTORM WILL BE...
  NEAR LA PORTE CITY AROUND 845 PM CDT

HAIL UP TO THE SIZE OF QUARTERS IS LIKELY IN THE WARNED AREA.

FREQUENT DEADLY LIGHTNI%NG IS OCCURRING. AVOID USING THE TELEPHONE OR
OTHER ELECTRICAL EQUIPMENT SUCH AS COMPUTERS AND TELEVISIONS.

LAT...LON 4231 9228 4221 9208 4240 9207 4255 9208

NNNN

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 7:11 PM CDTSevere Thunderstorm WarningDMXBlack Hawk, Bremer44 min
Apr 19, 8:24 PM CDTSevere Thunderstorm WarningDMXMahaska, Monroe36 min
Apr 20, 4:37 AM CDTSevere Thunderstorm WarningDMXUnion33 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2000Every severe thunderstorm warning in 2000

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.