Alert archive / Iowa / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 82, NWS Des Moines, IA

May 8, 2002Jasper County, Mahaska County, Poweshiek County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 8, 2002, 8:26 PM CDT for Jasper County, Mahaska County, Poweshiek County, Iowa. It was in force for 49 min. 7 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
May 8, 2002, 8:26 PM CDT (01:26 UTC)
Expired
May 8, 2002, 9:15 PM CDT
In force
49 min
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Jasper County, IA, Mahaska County, IA, Poweshiek County, IA

The radar

The Des Moines radar (KDMX), 83 km from the middle of the area, began a volume at 01:25 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.

What was reported inside it

TimeReportWhereRemark
May 8, 8:45 PM CDTThunderstorm Wind 52 ELeighton, IA
May 8, 8:48 PM CDTThunderstorm Wind 61 EOskaloosa, IA
May 8, 8:57 PM CDTHail 1New Sharon, IA
May 8, 8:59 PM CDTHail 1Searsboro, IA
May 8, 9:03 PM CDTThunderstorm Wind 65 ESearsboro, IA
May 8, 9:03 PM CDTHail 1.75Searsboro, IA
May 8, 9:13 PM CDTHail 0.88Montezuma, 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 watch it was issued in

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

IssuedProductOfficeLasted
May 8, 5:30 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.4 hours before the alert went out and 187 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 2002-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1642 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 2002-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 square meters per square second.1939587897117Sfc1 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
1642 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
951 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
227 m²/s²
Significant tornado parameter
1.3
Supercell composite
6.8

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KDMX 090126
SVRDSM
IAC099-123-157-090215-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
826 PM CDT WED MAY 8 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN JASPER COUNTY IN CENTRAL IOWA
  SOUTHERN POWESHIEK COUNTY IN CENTRAL IOWA
  MAHASKA COUNTY IN SOUTH CENTRAL IOWA

* UNTIL 915 PM CDT

* AT 825 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE
  OF SEVERE THUNDERSTORMS FROM 5 MILES NORTHEAST OF REASNOR TO 15
  MILES SOUTHWEST OF LEIGHTON...OR FROM 34 MILES EAST OF DES MOINES
  TO 33 MILES WEST OF OTTUMWA...MOVING EAST AT 45 MPH.

* SEVERE THUNDERSTORMS WILL BE...

  NEAR SULLY AROUND 835 PM...
  NEAR LEIGHTON AROUND 840 PM...
  NEAR SEARSBORO AROUND 845 PM...
  NEAR NEW SHARON AROUND 850 PM...
  NEAR MONTEZUMA AROUND 855 PM AND
  NEAR BROOKLYN AROUND 900 PM.

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

HURRICANE FORCE WINDS OF 70 TO 80 MILES AN HOUR ARE LIKELY IN THE
WARNED AREA.

STAY AWAY FROM WINDOWS DURING A SEVERE STORM...WIND GUSTS OVER 70 MPH
COULD BLOW THEM OUT.

REMEMBER...SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITH LITTLE OR
NO ADVANCE WARNING.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1100 PM WEDNESDAY EVENING FOR
SOUTHERN IOWA.

JOHNSON

The office that day

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

IssuedProductOfficeCountiesLasted
May 8, 7:12 PM CDTSevere Thunderstorm WarningDMXRinggold48 min
May 8, 7:34 PM CDTSevere Thunderstorm WarningDMXClarke41 min
May 8, 7:36 PM CDTSevere Thunderstorm WarningDMXDecatur, Warren39 min
May 8, 7:55 PM CDTSevere Thunderstorm WarningDMXMarion65 min
May 8, 7:58 PM CDTSevere Thunderstorm WarningDMXWayne47 min
May 8, 8:01 PM CDTTornado WarningDMXMarion, Warren44 min
May 8, 8:16 PM CDTSevere Thunderstorm WarningDMXLucas, Monroe44 min
May 8, 8:36 PM CDTTornado WarningDMXMahaska, Marion39 min
May 8, 8:54 PM CDTTornado WarningDMXPoweshiek36 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2002Every severe thunderstorm warning in 2002

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; radar from the NEXRAD Level II archive.