Alert archive / Iowa / Tornado Warnings in 2015

Tornado Warning 5, NWS Des Moines, IA

May 10, 2015Calhoun County, Pocahontas County, Iowa

NWS Des Moines, IA issued this tornado warning at May 10, 2015, 8:12 PM CDT for Calhoun County, Pocahontas County, Iowa. It was in force for 33 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, 8:12 PM CDT (01:12 UTC)
Expired: May 10, 2015, 8:45 PM CDT
In force: 33 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Calhoun County, IA, Pocahontas County, IA

The radar

The Des Moines radar (KDMX), 115 km from the middle of the area, began a volume at 01:13 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, 8:15 PM CDT	TORNADO	1 Sw Manson, IA	TORNADO BOUNCING UP AND DOWN AND BECOMING RAIN WRAPPED.
May 10, 8:20 PM CDT	TORNADO	4 N Manson, IA	TORNADO ON GROUND AND BOUNCING/GOING BACK UP IN CLOUD.

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, 1.2 hours before the alert went out and 209 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.

345 
WFUS53 KDMX 110112
TORDMX
IAC025-151-110145-
/O.NEW.KDMX.TO.W.0005.150511T0112Z-150511T0145Z/

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

THE NATIONAL WEATHER SERVICE IN DES MOINES  HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHEASTERN POCAHONTAS COUNTY IN NORTHWESTERN IOWA...
  NORTH CENTRAL CALHOUN COUNTY IN WEST CENTRAL IOWA...

* UNTIL 845 PM CDT
    
* AT 811 PM CDT...A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO WAS LOCATED NEAR NORTH TWIN LAKE...OR 7 MILES NORTH OF
  ROCKWELL CITY...MOVING NORTHEAST AT 20 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 DANGEROUS STORM WILL BE NEAR...
  MANSON AROUND 820 PM CDT.

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

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 4271 9445 4257 9444 4247 9456 4249 9464
TIME...MOT...LOC 0111Z 218DEG 18KT 4250 9458 

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

$$

SKOW

2 follow-up statements

499 
WWUS53 KDMX 110115
SVSDMX

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

IAC025-151-110145-
/O.CON.KDMX.TO.W.0005.000000T0000Z-150511T0145Z/
POCAHONTAS IA-CALHOUN IA-
815 PM CDT SUN MAY 10 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 PM CDT FOR
SOUTHEASTERN POCAHONTAS AND NORTH CENTRAL CALHOUN COUNTIES...
    
AT 815 PM CDT...A CONFIRMED TORNADO WAS LOCATED OVER MANSON...OR 8
MILES NORTH OF ROCKWELL CITY...MOVING NORTHEAST AT 20 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 TORNADIC THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF
SOUTHEASTERN POCAHONTAS AND NORTH CENTRAL CALHOUN COUNTIES...
INCLUDING THE FOLLOWING LOCATIONS...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 4271 9445 4257 9444 4247 9456 4249 9464
TIME...MOT...LOC 0115Z 218DEG 18KT 4252 9456 

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

$$

SKOW

019 
WWUS53 KDMX 110126
SVSDMX

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

IAC025-110135-
/O.CAN.KDMX.TO.W.0005.000000T0000Z-150511T0145Z/
CALHOUN IA-
826 PM CDT SUN MAY 10 2015

...THE TORNADO WARNING FOR NORTH CENTRAL CALHOUN COUNTY IS
CANCELLED...
    
THE TORNADIC THUNDERSTORM WHICH PROMPTED THE WARNING HAS 
MOVED OUT OF THE WARNED AREA. THE WARNING HAS
BEEN CANCELLED.

LAT...LON 4259 9444 4256 9446 4256 9458 4271 9445
TIME...MOT...LOC 0125Z 216DEG 19KT 4258 9451 

$$

IAC151-110145-
/O.CON.KDMX.TO.W.0005.000000T0000Z-150511T0145Z/
POCAHONTAS IA-
826 PM CDT SUN MAY 10 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 845 PM CDT FOR
SOUTHEASTERN POCAHONTAS COUNTY...
    
AT 825 PM CDT...A CONFIRMED TORNADO WAS LOCATED NEAR MANSON...OR 13
MILES SOUTHEAST OF POCAHONTAS...MOVING NORTHEAST AT 20 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 TORNADIC THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF
SOUTHEASTERN POCAHONTAS COUNTY.

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 4259 9444 4256 9446 4256 9458 4271 9445
TIME...MOT...LOC 0125Z 216DEG 19KT 4258 9451 

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, 7:43 PM CDT	Tornado Warning Tornado observed	DMX	Calhoun	32 min
May 10, 8:02 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	28 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.