Alert archive / Iowa / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 46, NWS La Crosse, WI

July 7, 2003Floyd County, Iowa

NWS La Crosse, WI issued this severe thunderstorm warning at Jul 7, 2003, 1:45 AM CDT for Floyd County, Iowa. It was in force for 60 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: Jul 7, 2003, 1:45 AM CDT (06:45 UTC)
Expired: Jul 7, 2003, 2:45 AM CDT
In force: 60 min
Issued by: NWS La Crosse, WI
Area: Counties, with a storm outline in the text

County Floyd County, IA

The radar

The Des Moines radar (KDMX), 157 km from the middle of the area, began a volume at 06:45 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
Jul 6, 9:20 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 6.8 hours before the alert went out and 210 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: 2301 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 1006 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 8 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KARX 070645
SVRARX
IAC067-070745-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
145 AM CDT MON JUL 7 2003

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  FLOYD COUNTY IN NORTH CENTRAL IOWA

* UNTIL 245 AM CDT

* AT 145 AM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED A SEVERE
  THUNDERSTORM 9 MILES WEST OF MARBLE ROCK...OR ABOUT 20 MILES
  SOUTHWEST OF CHARLES CITY...MOVING NORTHEAST AT 20 MPH.

* THE SEVERE THUNDERSTORM IS EXPECTED TO BE...
  NEAR MARBLE ROCK...AND ROCKFORD AT 200 AM CDT...
  NEAR NORA SPRINGS AT 205 AM CDT...
  NEAR ROSEVILLE AT 210 AM CDT...
  NEAR OAKWOOD...AND RUDD AT 215 AM CDT...
  NEAR FLOYD CROSSING AT 225 AM CDT...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND GUSTS IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR
YOUR PROTECTION...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS.

LAT...LON 4298 9321 4283 9308 4292 9257 4322 9257
          4321 9302

$$

THOMPSON

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 7, 2:18 AM CDT	Severe Thunderstorm Warning	ARX	Chickasaw	57 min
Jul 7, 2:27 AM CDT	Severe Thunderstorm Warning	ARX	Mitchell	48 min
Jul 7, 3:09 AM CDT	Flash Flood Warning	ARX	Mitchell	111 min
Jul 7, 3:18 AM CDT	Severe Thunderstorm Warning	ARX	Howard, Mitchell	42 min
Jul 7, 3:48 AM CDT	Tornado Warning	ARX	Chickasaw	42 min
Jul 7, 4:06 AM CDT	Severe Thunderstorm Warning	ARX	Clayton, Fayette	39 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2003 Every severe thunderstorm warning 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.