Alert archive / Iowa / Tornado Warnings in 2015

Tornado Warning 4, NWS Des Moines, IA

May 10, 2015Calhoun County, Iowa

NWS Des Moines, IA issued this tornado warning at May 10, 2015, 7:43 PM CDT for Calhoun County, Iowa. It was in force for 32 min. 2 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: May 10, 2015, 7:43 PM CDT (00:43 UTC)
Expired: May 10, 2015, 8:15 PM CDT
In force: 32 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Observed
Hail: 0.75 in

County Calhoun County, IA

The radar

The Des Moines radar (KDMX), 106 km from the middle of the area, began a volume at 01:03 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
May 10, 8:04 PM CDT	TORNADO	3 Ese Jolley, IA	TORNADO ON THE GROUND HEADING TOWARD SOUTH TWIN LAKES WILDLIFE REFUGE.
May 10, 8:15 PM CDT	TORNADO	1 Sw Manson, IA	TORNADO BOUNCING UP AND DOWN AND BECOMING RAIN WRAPPED.

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

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.7 hours before the alert went out and 186 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: 22 J/kg
Mixed-layer CIN: -186 J/kg
Mixed-layer LCL: 1224 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 61 m²/s²
0-3 km storm-relative helicity: 106 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

938 
WFUS53 KDMX 110043
TORDMX
IAC025-110115-
/O.NEW.KDMX.TO.W.0004.150511T0043Z-150511T0115Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
743 PM CDT SUN MAY 10 2015

THE NATIONAL WEATHER SERVICE IN DES MOINES  HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL CALHOUN COUNTY IN WEST CENTRAL IOWA...

* UNTIL 815 PM CDT

* AT 742 PM CDT...A CONFIRMED TORNADO WAS LOCATED 5 MILES NORTH OF
  LAKE CITY...OR 5 MILES SOUTHWEST OF ROCKWELL CITY...MOVING
  NORTHEAST AT 30 MPH.

  HAZARD...DAMAGING TORNADO. 

  SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. 

  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. 

* THE TORNADO WILL BE NEAR...
  ROCKWELL CITY AROUND 755 PM CDT.
  NORTH TWIN LAKE AND SOUTH TWIN LAKE AROUND 800 PM CDT.
  MANSON AROUND 810 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE TWIN
LAKES...TWIN LAKES STATE PARK AND ROCKWELL CITY MUNICIPAL AIRPORT.

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 4230 9468 4232 9476 4253 9467 4252 9444
TIME...MOT...LOC 0042Z 208DEG 27KT 4234 9470 

TORNADO...OBSERVED
HAIL...<.75IN

$$

SKOW

2 follow-up statements

215 
WWUS53 KDMX 110053
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
753 PM CDT SUN MAY 10 2015

IAC025-110115-
/O.CON.KDMX.TO.W.0004.000000T0000Z-150511T0115Z/
CALHOUN IA-
753 PM CDT SUN MAY 10 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 815 PM CDT FOR
NORTHEASTERN CALHOUN COUNTY...
    
AT 753 PM CDT...A CONFIRMED TORNADO WAS LOCATED OVER ROCKWELL CITY...
MOVING NORTHEAST AT 30 MPH.

HAZARD...DAMAGING TORNADO. 

SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. 

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 TORNADO WILL BE NEAR...
  SOUTH TWIN LAKE AROUND 800 PM CDT.
  NORTH TWIN LAKE AROUND 805 PM CDT.
  MANSON AROUND 815 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE TWIN
LAKES...TWIN LAKES STATE PARK AND ROCKWELL CITY MUNICIPAL AIRPORT.

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 4237 9462 4237 9472 4253 9467 4252 9448
TIME...MOT...LOC 0053Z 207DEG 26KT 4240 9466 

TORNADO...OBSERVED
HAIL...<.75IN

$$

SKOW

544 
WWUS53 KDMX 110101
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
801 PM CDT SUN MAY 10 2015

IAC025-110115-
/O.CON.KDMX.TO.W.0004.000000T0000Z-150511T0115Z/
CALHOUN IA-
801 PM CDT SUN MAY 10 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 815 PM CDT FOR NORTH
CENTRAL CALHOUN COUNTY...
    
AT 800 PM CDT...A CONFIRMED TORNADO WAS LOCATED OVER SOUTH TWIN
LAKE...OR NEAR ROCKWELL CITY...MOVING NORTHEAST AT 30 MPH.

HAZARD...DAMAGING TORNADO. 

SOURCE...WEATHER SPOTTERS CONFIRMED TORNADO. 

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 TORNADO WILL BE NEAR...
  MANSON AROUND 815 PM CDT.

OTHER LOCATIONS IMPACTED BY THIS TORNADIC THUNDERSTORM INCLUDE TWIN
LAKES AND TWIN LAKES STATE PARK.

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 4242 9461 4242 9468 4253 9464 4253 9457
      4252 9451
TIME...MOT...LOC 0100Z 207DEG 27KT 4245 9462 

TORNADO...OBSERVED
HAIL...<.75IN

$$

SKOW

The office that day

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

Issued	Product	Office	Counties	Lasted
May 10, 7:10 PM CDT	Special Weather Statement	DMX	Cass	50 min
May 10, 7:15 PM CDT	Tornado Warning Tornado observed	DMX	Calhoun, Carroll	30 min
May 10, 7:37 PM CDT	Tornado Warning	DMX	Pocahontas	23 min
May 10, 8:02 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	28 min
May 10, 8:12 PM CDT	Tornado Warning	DMX	Calhoun, Pocahontas	33 min
May 10, 8:18 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Sac	27 min
May 10, 8:41 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Pocahontas	49 min
May 10, 9:32 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Madison	18 min
May 10, 10:09 PM CDT	Special Weather Statement	DMX	Boone	36 min
May 11, 12:13 AM CDT	Special Weather Statement	DMX	Worth	17 min

Nearby

Tornado Warnings in Iowa, 2015 Every tornado warning in 2015 Tornadoes in 2015

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.