Alert archive / Iowa / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 29, NWS Des Moines, IA

May 1, 2012Humboldt County, Webster County, Wright County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 1, 2012, 11:24 PM CDT for Humboldt County, Webster County, Wright County, Iowa. It was in force for 51 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: May 1, 2012, 11:24 PM CDT (04:24 UTC)
Expired: May 2, 2012, 12:15 AM CDT
In force: 51 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Humboldt County, IA, Webster County, IA, Wright County, IA

The radar

The Des Moines radar (KDMX), 110 km from the middle of the area, began a volume at 04:24 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 1, 11:34 PM CDT	TSTM WND GST 60	2 Nnw Fort Dodge, IA	TRAINED SPOTTER REPORTED QUARTER SIZED HAIL BLOWING VERTICALLY AGAINST THE WINDOW. ESTIMATED AT LEAST 60 MPH WIND GUSTS

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 1, 9:18 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 4.4 hours before the alert went out and 243 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: 279 J/kg
Mixed-layer CIN: -111 J/kg
Mixed-layer LCL: 1279 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 227 m²/s²
0-3 km storm-relative helicity: 393 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 4.9

Open this sounding in Storm Lab

The text

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

879 
WUUS53 KDMX 020424
SVRDMX
IAC091-187-197-020515-
/O.NEW.KDMX.SV.W.0029.120502T0424Z-120502T0515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1124 PM CDT TUE MAY 1 2012

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN HUMBOLDT COUNTY IN NORTH CENTRAL IOWA...
  NORTHERN WEBSTER COUNTY IN CENTRAL IOWA...
  WEST CENTRAL WRIGHT COUNTY IN NORTH CENTRAL IOWA...

* UNTIL 1215 AM CDT

* AT 1121 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  FORT DODGE...AND MOVING NORTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  EAGLE GROVE...CLARION...FORT DODGE AIRPORT...BADGER...VINCENT...
  THOR...HARDY...GOLDFIELD...RENWICK AND CLARION AIRPORT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MOVE TO AN INTERIOR ROOM AND STAY AWAY FROM WINDOWS. IF YOU ARE IN A
MOBILE HOME...GET OUT NOW...AND SEEK SHELTER IN A REINFORCED
BUILDING.

&&

LAT...LON 4286 9400 4275 9370 4243 9420 4255 9436
TIME...MOT...LOC 0424Z 227DEG 30KT 4255 9422
WIND...HAIL 60MPH 1.00IN

$$

DONAVON

2 follow-up statements

251 
WWUS53 KDMX 020440
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1140 PM CDT TUE MAY 1 2012

IAC091-187-197-020515-
/O.CON.KDMX.SV.W.0029.000000T0000Z-120502T0515Z/
HUMBOLDT IA-WRIGHT IA-WEBSTER IA-
1140 PM CDT TUE MAY 1 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTH CENTRAL
WEBSTER...WEST CENTRAL WRIGHT AND SOUTHEASTERN HUMBOLDT COUNTIES
UNTIL 1215 AM CDT...

AT 1135 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 8 MILES
NORTH OF FORT DODGE...MOVING NORTHEAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
  EAGLE GROVE...CLARION...THOR...HARDY...GOLDFIELD...RENWICK AND
  CLARION AIRPORT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PREPARE FOR LARGE HAIL...DAMAGING WINDS AND DEADLY CLOUD TO GROUND
LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY
INSIDE A REINFORCED BUILDING AND AWAY FROM WINDOWS.

AT 1134 PM...SPOTTERS REPORTED QUARTER SIZED HAIL AND WINDS IN 
EXCESS OF 60 MPH 2 MILES NORTH OF THE FORT DODGE AIRPORT.

&&

LAT...LON 4248 9412 4260 9429 4286 9400 4275 9370
TIME...MOT...LOC 0440Z 227DEG 30KT 4264 9409
WIND...HAIL 60MPH 1.00IN

$$

DONAVON

749 
WWUS53 KDMX 020516
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1216 AM CDT WED MAY 2 2012

IAC091-187-197-020526-
/O.EXP.KDMX.SV.W.0029.000000T0000Z-120502T0515Z/
HUMBOLDT IA-WRIGHT IA-WEBSTER IA-
1216 AM CDT WED MAY 2 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WEBSTER...WEST
CENTRAL WRIGHT AND SOUTHEASTERN HUMBOLDT COUNTIES HAS EXPIRED...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
HOWEVER GUSTY WINDS ARE STILL POSSIBLE WITH THIS THUNDERSTORM.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 200 AM CDT.

LAT...LON 4248 9412 4260 9429 4286 9400 4275 9370
TIME...MOT...LOC 0440Z 227DEG 30KT 4264 9409

$$

BEERENDS

The office that day

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

Issued	Product	Office	Counties	Lasted
May 1, 9:59 PM CDT	Severe Thunderstorm Warning	DMX	Emmet, Palo Alto	46 min
May 1, 10:45 PM CDT	Severe Thunderstorm Warning	DMX	Kossuth, Palo Alto	45 min
May 1, 11:35 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	25 min
May 2, 12:01 AM CDT	Severe Thunderstorm Warning	DMX	Carroll, Crawford, Sac	44 min
May 2, 12:38 AM CDT	Severe Thunderstorm Warning	DMX	Carroll, Crawford, Greene, Sac	52 min
May 2, 1:02 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Guthrie	43 min
May 2, 1:07 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Carroll, Dallas, Greene, Guthrie	38 min
May 2, 1:24 AM CDT	Tornado Warning	DMX	Boone	36 min
May 2, 1:27 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Hamilton, Story, Webster	48 min
May 2, 1:39 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Polk, Story	51 min
May 2, 1:47 AM CDT	Tornado Warning	DMX	Boone, Hamilton, Hardin, Story	28 min
May 2, 1:53 AM CDT	Severe Thunderstorm Warning	DMX	Dallas, Polk	52 min
May 2, 2:04 AM CDT	Severe Thunderstorm Warning	DMX	Grundy, Hardin, Marshall, Story	41 min
May 2, 2:37 AM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Grundy, Marshall, Tama	36 min
May 2, 3:18 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion, Poweshiek	15 min
May 2, 3:46 PM CDT	Flash Flood Watch	DMX	Black Hawk, Bremer, Butler, Cerro Gordo, Franklin, Grundy and 1 more	12 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2012 Every severe thunderstorm warning in 2012

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.