Alert archive / Iowa / Tornado Warnings in 2009
Tornado Warning 28, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this tornado warning at Jun 21, 2009, 5:33 PM CDT for Lyon County, Sioux County, Iowa. It was in force for 27 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 21, 2009, 5:33 PM CDT (22:33 UTC)
- Expired
- Jun 21, 2009, 6:00 PM CDT
- In force
- 27 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
Counties Lyon County, IA, Sioux County, IA
The radar
The Sioux Falls radar (KFSD), 61 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.
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 21, 3:17 PM CDT | Tornado Watch | SPC | 8 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 10.6 hours before the alert went out and 218 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.
- Mixed-layer CAPE
- 564 J/kg
- Mixed-layer CIN
- -12 J/kg
- Mixed-layer LCL
- 482 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 228 m²/s²
- 0-3 km storm-relative helicity
- 210 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 3.1
The text
As transmitted, in the capitals the NWS used until 2016.
000 WFUS53 KFSD 212233 TORFSD IAC119-167-212300- /O.NEW.KFSD.TO.W.0028.090621T2233Z-090621T2300Z/ BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 533 PM CDT SUN JUN 21 2009 THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A * TORNADO WARNING FOR... SOUTHERN LYON COUNTY IN NORTHWEST IOWA NORTHERN SIOUX COUNTY IN NORTHWEST IOWA * UNTIL 600 PM CDT * AT 532 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED NEAR DOON...OR 11 MILES SOUTH OF ROCK RAPIDS... AND MOVING EAST AT 10 MPH. * THIS TORNADIC STORM WILL BE NEAR... RURAL LYON COUNTY THROUGH 550 PM CDT RURAL SIOUX COUNTY THROUGH 550 PM CDT AT 530 PM CDT...A TRAINED SPOTTER REPORTED A TORNADO NEAR THE SIOUX AND LYON COUNTY LINE SOUTHEAST OF DOON. PRECAUTIONARY/PREPAREDNESS ACTIONS... IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A STURDY SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS. && LAT...LON 4333 9602 4321 9602 4318 9623 4329 9626 TIME...MOT...LOC 2233Z 260DEG 10KT 4326 9618 $$ SCHUMACHER
2 follow-up statements
000 WWUS53 KFSD 212247 SVSFSD SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 547 PM CDT SUN JUN 21 2009 IAC119-167-212300- /O.CON.KFSD.TO.W.0028.000000T0000Z-090621T2300Z/ LYON IA-SIOUX IA- 547 PM CDT SUN JUN 21 2009 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 PM CDT FOR NORTHERN SIOUX AND SOUTHERN LYON COUNTIES... AT 546 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A TORNADO. THIS TORNADO WAS LOCATED NEAR DOON...OR 11 MILES SOUTH OF ROCK RAPIDS...MOVING EAST AT 10 MPH. THE TORNADO WILL BE NEAR... THE LYON AND SIOUX COUNTY LINE EAST OF DOON... PRECAUTIONARY/PREPAREDNESS ACTIONS... WHEN A TORNADO WARNING IS ISSUED BASED ON DOPPLER RADAR...IT MEANS THAT STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY ALREADY BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY. IF YOU ARE IN THE PATH OF THIS DANGEROUS STORM...MOVE INDOORS AND TO THE LOWEST LEVEL OF THE BUILDING. STAY AWAY FROM WINDOWS. IF DRIVING...DO NOT SEEK SHELTER UNDER A HIGHWAY OVERPASS. A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT SUNDAY EVENING FOR NORTHWEST IOWA AND SOUTHWEST MINNESOTA. && LAT...LON 4333 9602 4321 9602 4318 9623 4329 9626 TIME...MOT...LOC 2246Z 260DEG 10KT 4327 9613 $$ SCHUMACHER
000 WWUS53 KFSD 212254 SVSFSD SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 554 PM CDT SUN JUN 21 2009 IAC119-167-212300- /O.CON.KFSD.TO.W.0028.000000T0000Z-090621T2300Z/ LYON IA-SIOUX IA- 554 PM CDT SUN JUN 21 2009 ...A TORNADO WARNING REMAINS IN EFFECT UNTIL 600 PM CDT FOR NORTHERN SIOUX AND SOUTHERN LYON COUNTIES... AT 551 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A TORNADO. THIS TORNADO WAS LOCATED 7 MILES SOUTHEAST OF DOON...OR 15 MILES SOUTH OF ROCK RAPIDS...MOVING EAST AT 10 MPH. THIS IS A NEW TORNADIC CIRCULATION AND WILL BE MOVING NORTH OF HULL TOWARD BOYDEN. A TRAINED WEATHER SPOTTER REPORTED A ROTATING WALL CLOUD NEAR HULL AT 550 PM CDT. PRECAUTIONARY/PREPAREDNESS ACTIONS... WHEN A TORNADO WARNING IS ISSUED BASED ON DOPPLER RADAR...IT MEANS THAT STRONG ROTATION HAS BEEN DETECTED IN THE STORM. A TORNADO MAY ALREADY BE ON THE GROUND...OR IS EXPECTED TO DEVELOP SHORTLY. IF YOU ARE IN THE PATH OF THIS DANGEROUS STORM...MOVE INDOORS AND TO THE LOWEST LEVEL OF THE BUILDING. STAY AWAY FROM WINDOWS. IF DRIVING...DO NOT SEEK SHELTER UNDER A HIGHWAY OVERPASS. A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT SUNDAY EVENING FOR NORTHWEST IOWA AND SOUTHWEST MINNESOTA. && LAT...LON 4333 9602 4321 9602 4318 9623 4329 9626 TIME...MOT...LOC 2253Z 267DEG 10KT 4322 9613 $$ SCHUMACHER
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 21, 4:56 PM CDT | Tornado Warning | FSD | Lyon, Sioux | 34 min |
| Jun 21, 5:56 PM CDT | Tornado Warning | FSD | Lyon, Sioux | 49 min |
Nearby
Tornado Warnings in Iowa, 2009Every tornado warning in 2009Tornadoes in 2009
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.