Alert archive / Iowa / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 29, NWS Des Moines, IA

April 18, 2002Adams County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Apr 18, 2002, 5:00 PM CDT for Adams County, Iowa. It was in force for 45 min. 2 reports 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, 5:00 PM CDT (22:00 UTC)
Expired: Apr 18, 2002, 5:45 PM CDT
In force: 45 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Adams County, IA

The radar

The Des Moines radar (KDMX), 114 km from the middle of the area, began a volume at 22:00 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, 5:25 PM CDT	Hail 1	Nodaway, IA
Apr 18, 5:37 PM CDT	Hail 0.88	Nodaway, 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, 10.0 hours before the alert went out and 138 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 182200
SVRDSM
IAC003-182245-

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

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  ADAMS COUNTY IN SOUTHWEST IOWA

* UNTIL 545 PM CDT

* AT 455 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 18 MILES SOUTHWEST OF CORNING...OR ABOUT 49
  MILES SOUTHEAST OF COUNCIL BLUFFS...MOVING NORTHEAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE...

  NEAR CORNING AROUND 545 PM.

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

VERY STRONG WINDS UP TO 60 MPH ARE LIKELY IN THE WARNED AREA.

A SEVERE THUNDERSTORM CAN PRODUCE HAIL LARGER THAN THREE QUARTERS OF
AN INCH AND WINDS IN EXCESS OF 58 MPH.

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

LAT...LON 4116 9493 4091 9492 4091 9450 4116 9452

KULA

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, 5:07 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, 5:34 PM CDT	Severe Thunderstorm Warning	DMX	Greene	26 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.