Alert archive / Iowa / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 35, NWS Des Moines, IA

April 18, 2002Greene County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Apr 18, 2002, 5:34 PM CDT for Greene County, Iowa. It was in force for 26 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 18, 2002, 5:34 PM CDT (22:34 UTC)
Expired: Apr 18, 2002, 6:00 PM CDT
In force: 26 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Greene County, IA

The radar

The Des Moines radar (KDMX), 55 km from the middle of the area, began a volume at 22:35 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

Time	Report	Where	Remark
Apr 18, 5:45 PM CDT	Hail 1.5	Rippey, 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.

Issued	Product	Office	Lasted
Apr 18, 4:15 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.6 hours before the alert went out and 182 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2266 J/kg
Mixed-layer CIN: -161 J/kg
Mixed-layer LCL: 1005 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 396 m²/s²
0-3 km storm-relative helicity: 481 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.3

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KDMX 182234
SVRDSM
IAC073-182300-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
534 PM CDT THU APR 18 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN GREENE COUNTY IN WEST CENTRAL IOWA

* UNTIL 600 PM CDT

* AT 530 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 10 MILES SOUTHWEST OF RIPPEY...OR ABOUT 42
  MILES NORTHWEST OF DES MOINES...MOVING NORTHEAST AT 40 MPH.

* THE SEVERE THUNDERSTORM WILL BE...

  NEAR RIPPEY AROUND 545 PM.

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

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

A TORNADO WATCH REMAINS IN EFFECT UNTIL 900 PM THURSDAY EVENING FOR
IOWA.

LAT...LON 4192 9443 4187 9446 4186 9418 4208 9418

JAW

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 17, 9:09 PM CDT	Severe Thunderstorm Warning	DMX	Audubon	66 min
Apr 17, 9:31 PM CDT	Severe Thunderstorm Warning	DMX	Carroll, Crawford	59 min
Apr 17, 10:15 PM CDT	Severe Thunderstorm Warning	DMX	Audubon	45 min
Apr 17, 10:24 PM CDT	Severe Thunderstorm Warning	DMX	Carroll, Greene	66 min
Apr 17, 10:27 PM CDT	Tornado Warning	DMX	Audubon	33 min
Apr 17, 10:39 PM CDT	Tornado Warning	DMX	Carroll	36 min
Apr 17, 10:58 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	47 min
Apr 17, 11:05 PM CDT	Tornado Warning	DMX	Greene	40 min
Apr 17, 11:34 PM CDT	Tornado Warning	DMX	Boone	41 min
Apr 17, 11:47 PM CDT	Severe Thunderstorm Warning	DMX	Palo Alto, Pocahontas	43 min
Apr 18, 12:01 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Hamilton, Story	59 min
Apr 18, 12:20 AM CDT	Tornado Warning	DMX	Boone	25 min
Apr 18, 12:28 AM CDT	Severe Thunderstorm Warning	DMX	Palo Alto	47 min
Apr 18, 12:34 AM CDT	Severe Thunderstorm Warning	DMX	Kossuth	56 min
Apr 18, 12:59 AM CDT	Severe Thunderstorm Warning	DMX	Hamilton, Hardin	61 min
Apr 18, 1:34 AM CDT	Severe Thunderstorm Warning	DMX	Butler, Franklin	56 min
Apr 18, 2:19 AM CDT	Severe Thunderstorm Warning	DMX	Bremer	41 min
Apr 18, 5:00 PM CDT	Severe Thunderstorm Warning	DMX	Adams	45 min
Apr 18, 5:07 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	38 min
Apr 18, 5:10 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton	35 min
Apr 18, 5:22 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	53 min
Apr 18, 5:23 PM CDT	Severe Thunderstorm Warning	DMX	Hardin	37 min
Apr 18, 5:27 PM CDT	Severe Thunderstorm Warning	DMX	Boone	33 min
Apr 18, 5:41 PM CDT	Severe Thunderstorm Warning	DMX	Story	34 min
Apr 18, 5:47 PM CDT	Severe Thunderstorm Warning	DMX	Boone	43 min
Apr 18, 5:53 PM CDT	Severe Thunderstorm Warning	DMX	Taylor	52 min
Apr 18, 6:00 PM CDT	Severe Thunderstorm Warning	DMX	Polk	60 min
Apr 18, 6:04 PM CDT	Tornado Warning	DMX	Grundy, Hardin	56 min
Apr 18, 6:06 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie, Madison	24 min
Apr 18, 6:14 PM CDT	Tornado Warning	DMX	Dallas	61 min
Apr 18, 6:18 PM CDT	Severe Thunderstorm Warning	DMX	Story	42 min
Apr 18, 6:40 PM CDT	Severe Thunderstorm Warning	DMX	Ringgold	50 min
Apr 18, 6:45 PM CDT	Severe Thunderstorm Warning	DMX	Polk	60 min
Apr 18, 6:52 PM CDT	Tornado Warning	DMX	Polk	23 min
Apr 18, 6:55 PM CDT	Severe Thunderstorm Warning	DMX	Madison, Warren	65 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2002 Every 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.