Alert archive / Iowa / Tornado Warnings in 2016

Tornado Warning 10, NWS Des Moines, IA

September 21, 2016Butler County, Iowa

NWS Des Moines, IA issued this tornado warning at Sep 21, 2016, 6:17 PM CDT for Butler County, Iowa. It was in force for 43 min. 4 reports 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, 6:17 PM CDT (23:17 UTC)
Expired: Sep 21, 2016, 7:00 PM CDT
In force: 43 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Butler County, IA

The radar

The Des Moines radar (KDMX), 147 km from the middle of the area, began a volume at 23:17 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.
Sep 21, 6:38 PM CDT	TSTM WND DMG	2 Ene Greene, IA	OBSERVED TREE DAMAGE IN STORM CHASER LIVE VIDEO STREAM. MULTIPLE LARGE TREE LIMBS DOWN.
Sep 21, 6:40 PM CDT	TSTM WND DMG	Greene, IA	TREES DOWN ON ROOFS AND POWER LINES. EXTENT OF DAMAGE UNKNOWN. TIME ESTIMATED FROM RADAR.
Sep 21, 6:45 PM CDT	TSTM WND DMG	Greene, IA	WIDESPREAD TREE DAMAGE THROUGHOUT TOWN. SEVERAL TREES ON HOUSES. .

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, 11.3 hours before the alert went out and 231 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.

683 
WFUS53 KDMX 212317
TORDMX
IAC023-220000-
/O.NEW.KDMX.TO.W.0010.160921T2317Z-160922T0000Z/

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

THE NATIONAL WEATHER SERVICE IN DES MOINES  HAS ISSUED A

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

* UNTIL 700 PM CDT.

* AT 617 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. 

  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 TORNADIC THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF
  NORTHEASTERN 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 4284 9293 4291 9293 4291 9255 4278 9256
TIME...MOT...LOC 2317Z 287DEG 14KT 4290 9277 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

REV

2 follow-up statements

895 
WWUS53 KDMX 212328
SVSDMX

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

IAC023-220000-
/O.CON.KDMX.TO.W.0010.000000T0000Z-160922T0000Z/
BUTLER IA-
628 PM CDT WED SEP 21 2016

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR
NORTHEASTERN BUTLER COUNTY...
    
AT 627 PM CDT...A CONFIRMED TORNADO WAS LOCATED NEAR GREENE...OR 10
MILES NORTHEAST OF ALLISON...MOVING EAST AT 15 MPH.

HAZARD...DAMAGING TORNADO AND QUARTER SIZE HAIL. 

SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. AT 624 PM A BRIEF ROPE
         TORNADO TOUCHED DOWN JUST 4 MILES WNW OF GREENE IOWA NEAR
         THE FLOYD BUTLER COUNTY LINE. 

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. 

LOCATIONS IMPACTED INCLUDE...
GREENE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. 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 4284 9293 4291 9293 4291 9255 4278 9256
TIME...MOT...LOC 2327Z 287DEG 14KT 4289 9272 

TORNADO...OBSERVED
HAIL...1.00IN

$$

REV

509 
WWUS53 KDMX 212340
SVSDMX

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

IAC023-220000-
/O.CON.KDMX.TO.W.0010.000000T0000Z-160922T0000Z/
BUTLER IA-
640 PM CDT WED SEP 21 2016

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM CDT FOR
NORTHEASTERN BUTLER COUNTY...
    
AT 638 PM CDT...A CONFIRMED TORNADO WAS LOCATED NEAR GREENE...OR 11
MILES NORTHEAST OF ALLISON...MOVING EAST AT 25 MPH.

HAZARD...DAMAGING TORNADO AND QUARTER SIZE HAIL. 

SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. AT 624 PM A BRIEF ROPE
         TORNADO TOUCHED DOWN JUST 4 MILES WNW OF GREENE IOWA NEAR
         THE FLOYD BUTLER COUNTY LINE. STRONG ROTATION CONTINUES TO
         BE INDICATED BY RADAR JUST NORTHEAST OF GREENE IOWA ALONG
         THE FLOYD BUTLER COUNTY LINE...OR ABOUT 4 MILES SOUTHWEST
         OF POWERSVILLE 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. 

LOCATIONS IMPACTED INCLUDE...
GREENE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TO REPEAT...A TORNADO IS ON THE GROUND. 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 4284 9292 4291 9292 4291 9255 4278 9256
TIME...MOT...LOC 2338Z 274DEG 22KT 4290 9269 

TORNADO...OBSERVED
HAIL...1.00IN

$$

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, 5:19 PM CDT	Tornado Warning	DMX	Butler	56 min
Sep 21, 5:45 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Worth	45 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.