Alert archive / Iowa / Tornado Warnings in 2002

Tornado Warning 12, NWS Des Moines, IA

April 27, 2002Union County, Iowa

NWS Des Moines, IA issued this tornado warning at Apr 27, 2002, 6:36 PM CDT for Union 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
Apr 27, 2002, 6:36 PM CDT (23:36 UTC)
Expired
Apr 27, 2002, 7:00 PM CDT
In force
24 min
Issued by
NWS Des Moines, IA
Area
Counties, with a storm outline in the text

County Union County, IA

The radar

The Des Moines radar (KDMX), 85 km from the middle of the area, began a volume at 23:40 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 watch it was issued in

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

IssuedProductOfficeLasted
Apr 27, 3:30 PM CDTTornado WatchSPC5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.6 hours before the alert went out and 180 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, Omaha, NE at 12:00Z on 2002-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLEL10008507005003002001001 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, Omaha, NE at 12:00Z on 2002-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 164 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
471 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
164 m²/s²
0-3 km storm-relative helicity
277 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 272336
TORDSM
IAC175-280000-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
636 PM CDT SAT APR 27 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHEASTERN UNION COUNTY IN SOUTH CENTRAL IOWA

* UNTIL 700 PM CDT

* AT 635 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  TORNADO 3 MILES NORTHWEST OF AFTON...OR ABOUT 48 MILES SOUTHWEST OF
  DES MOINES...MOVING NORTHEAST AT 35 MPH.

* THE TORNADO WILL BE...

  9 MILES NORTHWEST OF THAYER AROUND 645 PM AND
  4 MILES NORTHWEST OF LORIMOR AROUND 650 PM.

IF YOU ARE CAUGHT OUTSIDE...GO TO A NEARBY REINFORCED BUILDING. AS A
LAST RESORT...GET IN A CULVERT OR DITCH AND COVER YOUR HEAD WITH YOUR
HANDS.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM SATURDAY EVENING FOR
IOWA. LAT...LON 4107 9441 4091 9405 4115 9403 4117 9430

JOHNSON

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 27, 6:58 PM CDTTornado WarningDMXMadison32 min

Nearby

Tornado Warnings in Iowa, 2002Every tornado warning in 2002Tornadoes 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.