Alert archive / Iowa / Tornado Warnings in 2003

Tornado Warning 20, NWS Des Moines, IA

June 23, 2003Pocahontas County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 23, 2003, 11:35 PM CDT for Pocahontas County, Iowa. It was in force for 40 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: Jun 23, 2003, 11:35 PM CDT (04:35 UTC)
Expired: Jun 24, 2003, 12:15 AM CDT
In force: 40 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Pocahontas County, IA

The radar

The Des Moines radar (KDMX), 142 km from the middle of the area, began a volume at 04:36 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.

Issued	Product	Office	Lasted
Jun 23, 8:55 PM CDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 4.6 hours before the alert went out and 249 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: 1955 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 1314 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 79 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 6.7

Open this sounding in Storm Lab

The text

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

306 
WFUS53 KDMX 240435
TORDMX
IAC151-240515-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1135 PM CDT MON JUN 23 2003

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  POCAHONTAS COUNTY IN NORTHWEST IOWA

* UNTIL 1215 AM CDT

* AT 1131 PM...RADAR INDICATED A THUNDERSTORM CAPABLE OF PRODUCING   
  A TORNADO 7 MILES SOUTHWEST OF POCAHONTAS...OR TWO MILES NORTHEAST 
  OF VARINA...OR ABOUT 34 MILES WEST OF FORT DODGE...MOVING EAST AT  
  30 MPH.

* THE STORM WILL BE...

  NEAR POCAHONTAS AROUND 1145 PM AND
  5 MILES SOUTH OF ROLFE AROUND MIDNIGHT.

THIS WARNING REPLACES THE SEVERE THUNDERSTORM WARNING PREVIOUSLY
ISSUED FOR THE WARNED AREA.

THIS IS A HAZARDOUS SITUATION. SEEK SHELTER IN A BASEMENT...OR IN AN
INTERIOR ROOM. STAY AWAY FROM WINDOWS. IF YOU ARE OUTSIDE OR IN A
CAR...SEEK SHELTER IN A REINFORCED BUILDING.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 100 AM TUESDAY MORNING FOR
WESTERN IOWA.

LAT...LON 4290 9490 4258 9490 4257 9448 4290 9450

JOHNSON

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 23, 11:03 PM CDT	Severe Thunderstorm Warning	DMX	Pocahontas	57 min
Jun 24, 12:08 AM CDT	Severe Thunderstorm Warning	DMX	Humboldt	37 min
Jun 24, 12:28 AM CDT	Severe Thunderstorm Warning	DMX	Sac	47 min
Jun 24, 1:14 AM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Webster	46 min
Jun 24, 1:22 AM CDT	Severe Thunderstorm Warning	DMX	Humboldt, Webster	53 min
Jun 24, 1:38 AM CDT	Severe Thunderstorm Warning	DMX	Greene, Webster	37 min

Nearby

Tornado Warnings in Iowa, 2003 Every tornado warning in 2003 Tornadoes in 2003

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.