Alert archive / Iowa / Tornado Warnings in 2016

Tornado Warning 9, NWS Des Moines, IA

September 21, 2016Butler County, Iowa

NWS Des Moines, IA issued this tornado warning at Sep 21, 2016, 5:19 PM CDT for Butler County, Iowa. It was in force for 56 min. 1 report 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: Sep 21, 2016, 5:19 PM CDT (22:19 UTC)
Expired: Sep 21, 2016, 6:15 PM CDT
In force: 56 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 1.5 in

County Butler County, IA

The radar

The Des Moines radar (KDMX), 146 km from the middle of the area, began a volume at 22:22 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
Sep 21, 6:24 PM CDT	TORNADO	4 W Greene, IA	BRIEF ROPE TORNADO TOUCHDOWN 4 MILES WEST TO POSSIBLE WNW OF GREENE.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 10.3 hours before the alert went out and 230 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: 515 J/kg
Mixed-layer CIN: -331 J/kg
Mixed-layer LCL: 738 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 136 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 8.5

Open this sounding in Storm Lab

The text

As transmitted.

047 
WFUS53 KDMX 212219
TORDMX
IAC023-212315-
/O.NEW.KDMX.TO.W.0009.160921T2219Z-160921T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
519 PM CDT WED SEP 21 2016

THE NATIONAL WEATHER SERVICE IN DES MOINES  HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN BUTLER COUNTY IN NORTH CENTRAL IOWA...

* UNTIL 615 PM CDT.

* AT 519 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR MARBLE ROCK...OR 15 MILES NORTHWEST OF
  ALLISON...MOVING EAST AT 15 MPH.

  HAZARD...TORNADO AND PING PONG BALL SIZE HAIL. 

  SOURCE...RADAR INDICATED ROTATION. 

  IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
           SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. 
           DAMAGE TO ROOFS...WINDOWS...AND VEHICLES WILL OCCUR.  
           TREE DAMAGE IS LIKELY. 

* THIS DANGEROUS STORM WILL BE NEAR...
  GREENE AROUND 550 PM CDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! MOVE TO A BASEMENT OR AN INTERIOR ROOM ON THE LOWEST
FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF YOU ARE OUTDOORS...IN A
MOBILE HOME...OR IN A VEHICLE...MOVE TO THE CLOSEST SUBSTANTIAL
SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4280 9269 4286 9303 4291 9303 4291 9264
TIME...MOT...LOC 2219Z 284DEG 15KT 4294 9295 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

REV

2 follow-up statements

152 
WWUS53 KDMX 212240
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
540 PM CDT WED SEP 21 2016

IAC023-212315-
/O.CON.KDMX.TO.W.0009.000000T0000Z-160921T2315Z/
BUTLER IA-
540 PM CDT WED SEP 21 2016

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 615 PM CDT FOR
NORTHWESTERN BUTLER COUNTY...
    
AT 539 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO
WAS LOCATED OVER GREENE...OR 11 MILES NORTH OF ALLISON...MOVING EAST
AT 15 MPH.

HAZARD...TORNADO AND PING PONG BALL SIZE HAIL. 

SOURCE...RADAR INDICATED ROTATION. AT 533 PM STORM SPOTTERS REPORTED
         A BRIEF TORNADO TOUCHDOWN IN FLOYD COUNTY 3 MILES EAST OF
         MARBLE ROCK.  

IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
         SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE 
         TO ROOFS...WINDOWS...AND VEHICLES WILL OCCUR.  TREE DAMAGE 
         IS LIKELY. 

THIS DANGEROUS STORM WILL BE NEAR...
  GREENE AROUND 545 PM CDT. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! MOVE TO A BASEMENT OR AN INTERIOR ROOM ON THE LOWEST
FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF YOU ARE OUTDOORS...IN A
MOBILE HOME...OR IN A VEHICLE...MOVE TO THE CLOSEST SUBSTANTIAL
SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4280 9269 4286 9303 4291 9303 4291 9264
TIME...MOT...LOC 2239Z 284DEG 15KT 4292 9284 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

REV

510 
WWUS53 KDMX 212255
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
555 PM CDT WED SEP 21 2016

IAC023-212315-
/O.CON.KDMX.TO.W.0009.000000T0000Z-160921T2315Z/
BUTLER IA-
555 PM CDT WED SEP 21 2016

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 615 PM CDT FOR
NORTHWESTERN BUTLER COUNTY...
    
AT 553 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO
WAS LOCATED OVER GREENE...OR 10 MILES NORTH OF ALLISON...MOVING EAST
AT 15 MPH.

HAZARD...TORNADO AND PING PONG BALL SIZE HAIL. 

SOURCE...RADAR INDICATED ROTATION. AT 533 PM STORM SPOTTERS REPORTED
         A BRIEF TORNADO TOUCHDOWN IN FLOYD COUNTY 3 MILES EAST OF
         MARBLE ROCK. SEVERAL ROTATING WALL CLOUDS ARE STILL ONGOING
         WITH THE STORM. A NEW WALL CLOUD HAS DEVELOPED NEAR GREENE
         IOWA.

IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WITHOUT 
         SHELTER. MOBILE HOMES WILL BE DAMAGED OR DESTROYED. DAMAGE 
         TO ROOFS...WINDOWS...AND VEHICLES WILL OCCUR.  TREE DAMAGE 
         IS LIKELY. 

THIS TORNADIC THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF
NORTHWESTERN BUTLER COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! MOVE TO A BASEMENT OR AN INTERIOR ROOM ON THE LOWEST
FLOOR OF A STURDY BUILDING. AVOID WINDOWS. IF YOU ARE OUTDOORS...IN A
MOBILE HOME...OR IN A VEHICLE...MOVE TO THE CLOSEST SUBSTANTIAL
SHELTER AND PROTECT YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 4280 9269 4286 9303 4291 9303 4291 9264
TIME...MOT...LOC 2253Z 284DEG 15KT 4291 9276 

TORNADO...RADAR INDICATED
HAIL...1.50IN

$$

REV

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 21, 3:26 PM CDT	Special Weather Statement	DMX	Cerro Gordo	49 min
Sep 21, 3:32 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	43 min
Sep 21, 4:23 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	37 min
Sep 21, 4:50 PM CDT	Flash Flood Warning	DMX	Cerro Gordo	6 hr
Sep 21, 4:57 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	31 min
Sep 21, 5:13 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Franklin	47 min
Sep 21, 5:45 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Worth	45 min
Sep 21, 6:17 PM CDT	Tornado Warning	DMX	Butler	43 min
Sep 21, 6:33 PM CDT	Flash Flood Warning	DMX	Cerro Gordo, Worth	6 hr
Sep 21, 6:44 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	46 min
Sep 21, 6:58 PM CDT	Flash Flood Warning	DMX	Butler	12 hr
Sep 21, 6:59 PM CDT	Tornado Warning	DMX	Bremer, Butler	46 min

Nearby

Tornado Warnings in Iowa, 2016 Every tornado warning in 2016 Tornadoes in 2016

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.