Alert archive / Iowa / Tornado Warnings in 2013

Tornado Warning 4, NWS Des Moines, IA

May 19, 2013Polk County, Story County, Iowa

NWS Des Moines, IA issued this tornado warning at May 19, 2013, 6:49 PM CDT for Polk County, Story County, Iowa. It was in force for 26 min. 14 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 19, 2013, 6:49 PM CDT (23:49 UTC)
Expired: May 19, 2013, 7:15 PM CDT
In force: 26 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Observed
Hail: 1.75 in

Counties Polk County, IA, Story County, IA

The radar

The Des Moines radar (KDMX), 11 km from the middle of the area, began a volume at 23:52 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 19, 6:56 PM CDT	TSTM WND GST 62	Grimes, IA	SCHOOLNET SITE
May 19, 7:00 PM CDT	TSTM WND DMG	1 Ssw Saylorville Lake, IA	DELAYED REPORT...TREE DOWN ON A POWER LINE.
May 19, 7:00 PM CDT	TSTM WND DMG	Grimes, IA	LARGE TREES DOWN OR SNAPPED OFF AROUND TOWN.
May 19, 7:00 PM CDT	TSTM WND GST 60	Polk City, IA	SCHOOLNET SITE
May 19, 7:04 PM CDT	TSTM WND DMG	2 N Saylorville Lake, IA	10 INCH DIAMETER TREE BRANCH DOWN IN POLK CITY
May 19, 7:06 PM CDT	TSTM WND DMG	6 Nnw Ankeny Airport, IA	SHINGLES AND SIDING TORN FROM SOME HOMES.
May 19, 7:06 PM CDT	TSTM WND GST 62	Ankeny, IA	SCHOOLNET SITE
May 19, 7:07 PM CDT	TSTM WND GST 75	Ankeny, IA
May 19, 7:08 PM CDT	TSTM WND DMG	5 Nnw Ankeny Airport, IA	GAS STATION CANOPY TORN OFF NEAR 36TH AND ANKENY BLVD
May 19, 7:08 PM CDT	TORNADO	Slater, IA	TORNADO REPORTED BETWEEN SLATER AND HUXLEY NEAR 538TH. STREET.
May 19, 7:10 PM CDT	TORNADO	1 S Huxley, IA
May 19, 7:10 PM CDT	TORNADO	2 S Slater, IA	TORNADO ON THE GROUND ABOUT 2 SOUTH OF SLATER
May 19, 7:16 PM CDT	HAIL 1	Ankeny, IA	WINDS ESTIMATED AT 60-70 MPH.
May 19, 7:16 PM CDT	HAIL 1	Ankeny, IA

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 19, 1:10 PM CDT	Tornado Watch	SPC	8 hr
May 19, 2:59 PM CDT	Tornado Watch	SPC	8 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.8 hours before the alert went out and 233 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1125 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 80 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

175 
WFUS53 KDMX 192349
TORDMX
IAC153-169-200015-
/O.NEW.KDMX.TO.W.0004.130519T2349Z-130520T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
649 PM CDT SUN MAY 19 2013

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN POLK COUNTY IN CENTRAL IOWA...
  SOUTHWESTERN STORY COUNTY IN CENTRAL IOWA...

* UNTIL 715 PM CDT

* AT 648 PM CDT...A CONFIRMED TORNADO WAS LOCATED 5 MILES EAST OF
  DALLAS CENTER...AND MOVING NORTHEAST AT 50 MPH.

  HAZARD...DAMAGING TORNADO AND GOLF BALL SIZE HAIL.

  SOURCE...RADAR CONFIRMED TORNADO.

  IMPACT...MOBILE HOMES WILL BE HEAVILY DAMAGED OR DESTROYED.
           SIGNIFICANT DAMAGE TO ROOFS...WINDOWS AND VEHICLES WILL
           OCCUR. FLYING DEBRIS WILL BE DEADLY TO PEOPLE AND ANIMALS.
           EXTENSIVE TREE DAMAGE IS LIKELY.

* LOCATIONS IMPACTED INCLUDE...
  GRIMES...URBANDALE...JOHNSTON...POLK CITY...ANKENY...HUXLEY...
  SAYLORVILLE LAKE...SAYLORVILLE...SHELDAHL...SLATER...ALLEMAN...
  ELKHART...CAMBRIDGE AND MAXWELL.

THIS INCLUDES INTERSTATE 80 BETWEEN MILE MARKERS 126 AND 132.

THIS INCLUDES INTERSTATE 35 BETWEEN MILE MARKERS 90 AND 111.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4160 9381 4186 9382 4187 9380 4186 9370
      4193 9370 4206 9347 4181 9335 4176 9335
TIME...MOT...LOC 2349Z 232DEG 44KT 4170 9387

TORNADO...OBSERVED
HAIL...1.75IN

$$

DONAVON

The office that day

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

Issued	Product	Office	Counties	Lasted
May 19, 1:07 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	23 min
May 19, 2:51 AM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Humboldt, Pocahontas, Sac, Webster	39 min
May 19, 3:04 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marion	26 min
May 19, 3:33 AM CDT	Severe Thunderstorm Warning	DMX	Emmet, Humboldt, Kossuth, Palo Alto	42 min
May 19, 3:55 AM CDT	Severe Thunderstorm Warning	DMX	Hancock, Wright	50 min
May 19, 4:19 AM CDT	Severe Thunderstorm Warning	DMX	Kossuth, Winnebago	56 min
May 19, 3:57 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	33 min
May 19, 4:34 PM CDT	Flash Flood Warning	DMX	Crawford	6 hr
May 19, 4:59 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Cass	46 min
May 19, 5:39 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Pocahontas, Webster	51 min
May 19, 5:43 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Cass, Guthrie	47 min
May 19, 5:45 PM CDT	Tornado Warning	DMX	Calhoun, Pocahontas, Webster	45 min
May 19, 6:10 PM CDT	Flash Flood Warning	DMX	Adair, Adams, Cass	6 hr
May 19, 6:14 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Dallas, Greene, Guthrie, Madison	46 min
May 19, 6:23 PM CDT	Severe Thunderstorm Warning	DMX	Humboldt, Kossuth	52 min
May 19, 6:27 PM CDT	Tornado Warning	DMX	Dallas, Guthrie, Madison	33 min
May 19, 6:35 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Madison, Warren	40 min
May 19, 6:42 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Polk, Story	48 min

Nearby

Tornado Warnings in Iowa, 2013 Every tornado warning in 2013 Tornadoes in 2013

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.