Alert archive / Iowa / Severe Thunderstorm Warnings in 2005

Severe Thunderstorm Warning 46, NWS Des Moines, IA

May 6, 2005Hamilton County, Webster County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 6, 2005, 11:26 PM CDT for Hamilton County, Webster County, Iowa. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 6, 2005, 11:26 PM CDT (04:26 UTC)
Expired: May 7, 2005, 12:15 AM CDT
In force: 49 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

Counties Hamilton County, IA, Webster County, IA

The radar

The Des Moines radar (KDMX), 76 km from the middle of the area, began a volume at 04:26 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 4.4 hours before the alert went out and 224 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: 1114 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 1756 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 38 m²/s²
0-3 km storm-relative helicity: 263 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.4

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KDMX 070427
SVRDMX
IAC079-187-070515-
/O.NEW.KDMX.SV.W.0046.050507T0426Z-050507T0515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1126 PM CDT FRI MAY 6 2005

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN HAMILTON COUNTY IN CENTRAL IOWA.
  EASTERN WEBSTER COUNTY IN CENTRAL IOWA.

* UNTIL 1215 AM CDT.

* AT 1122 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL.  THIS
  STORM WAS LOCATED 12 MILES EAST OF GOWRIE...OR 14 MILES SOUTHEAST
  OF FORT DODGE...AND MOVING NORTHEAST AT 10 MPH.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER MAINLY RURAL AREAS OF
  EASTERN WEBSTER AND WESTERN HAMILTON COUNTIES...INCLUDING THE
  LOCATION OF LEHIGH.

LAT...LON 4241 9420 4223 9413 4229 9387 4248 9390

$$

2 follow-up statements

000 
WWUS53 KDMX 070448
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1148 PM CDT FRI MAY 6 2005

IAC079-187-070515-
/O.CON.KDMX.SV.W.0046.000000T0000Z-050507T0515Z/
WEBSTER IA-HAMILTON IA-
1148 PM CDT FRI MAY 6 2005

...A SEVERE THUNDERSTORM WARNING CONTINUES FOR WESTERN HAMILTON AND
EASTERN WEBSTER COUNTIES UNTIL 1215 AM CDT...

AT 1143 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL.  THIS
STORM WAS LOCATED 14 MILES SOUTHWEST OF WEBSTER CITY...OR 17 MILES
SOUTHEAST OF FORT DODGE...AND MOVING NORTHEAST AT 10 MPH.

THE SEVERE THUNDERSTORM WILL BE...
  NEAR LEHIGH BY 1140 PM CDT.

THE LOCATION OF DAYTON IS ALSO IN THE PATH OF THIS SEVERE
THUNDERSTORM.

IF SEVERE WEATHER WAS OBSERVED...CONTACT THE NATIONAL WEATHER SERVICE
OFFICE IN DES MOINES AT 1-800-759-9276.

LAT...LON 4241 9420 4223 9413 4229 9387 4248 9390

$$

BOKSA

000 
WWUS53 KDMX 070515
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1216 AM CDT SAT MAY 7 2005

IAC079-187-070526-
/O.EXP.KDMX.SV.W.0046.000000T0000Z-050507T0515Z/
WEBSTER IA-HAMILTON IA-
1216 AM CDT SAT MAY 7 2005

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN HAMILTON AND EASTERN
WEBSTER COUNTIES HAS BEEN ALLOWED TO EXPIRE...

AT 1213 AM CDT...WEATHER SERVICE DOPPLER RADAR INDICATED THAT THE
THUNDERSTORMS WHICH PROMPTED THE WARNING HAVE WEAKENED...AND NO
LONGER POSE AN IMMEDIATE THREAT TO LIFE OR PROPERTY. THEREFORE...THE
SEVERE THUNDERSTORM WARNING HAS BEEN ALLOWED TO EXPIRE.

IF SEVERE WEATHER WAS OBSERVED...CONTACT THE NATIONAL WEATHER SERVICE
OFFICE IN DES MOINES AT 1-800-759-9276.

LAT...LON 4241 9420 4223 9413 4229 9387 4248 9390

$$

BOKSA

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at May 6, 3:22 PM CDT, 8 hours 4 minutes earlier.

Area forecast discussion, May 6, 3:22 PM CDT, 8 hours 4 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
322 PM CDT FRI MAY 6 2005

.DISCUSSION...
NUMEROUS CHANCES FOR THUNDERSTORMS OVER THE NEXT 7 DAYS AS A FRONTAL
BOUNDARY MEANDERS ACROSS THE CENTRAL PLAINS THROUGH MUCH OF THE
PERIOD. FORECAST CHALLENGES ARE TO DISTINGUISH PERIODS OF HIGHER
POPS AS WELL AS DRY PERIODS. WEAK REMNANT SFC BOUNDER HAS BEEN
SAGGING ACROSS NORTHERN IOWA MUCH OF THE DAY AND HAS PUSHED FARTHER
SOUTH THAN EXPECTED. OVERNIGHT A 50 KT LLJ IS PROGGED TO DEVELOP
ACROSS THE MISSOURI RIVER VALLEY AND INTERACT WITH A COUPLE 500 MB
IMPULSES THAT ARE CURRENTLY MOVING TOWARD THE REGION. THIS WILL
SPILL AN AREA OF SPEED CONVERGENCE AND KINEMATIC ENERGY INTO WESTERN
IOWA AND GIVE ADDITIONAL LIFT ALONG THE WEAK SFC BOUNDARY FOR
THUNDERSTORM DEVELOPMENT TONIGHT. 0-6KM BULK SHEAR PROFILES OF 15 TO
20 KTS FAIRLY WEAK AND SHOULD LIMIT SEVERE THREAT AS ANY STRONG
UPDRAFTS THAT DO DEVELOP WILL BE UNABLE TO MAINTAIN LONGEVITY. THAT
BEING SAID...A FEW PULSE SEVERE THUNDERSTORMS ARE POSSIBLE. LOW
PRESSURE DEVELOPING OVER THE DAKOTAS WILL RE-ENERGIZE THE SFC
BOUNDARY AND PULL IT BACK TO THE NORTH AS A WARM FRONT. WILL BE
QUITE UNSTABLE BY SATURDAY AFTERNOON...HOWEVER STORM CHANCES WILL BE
LIMITED BY THE LACK OF A FORCING MECHANISM...A CAPPING LAYER AROUND
850 MB AND CLOUD COVER. AN ABUNDANCE OF SUNSHINE MAY OVERCOME THIS
CAPPING THOUGH. THE LLJ SHIFTS OVER IA SATURDAY NIGHT AND WILL KEEP
THUNDERSTORM CHANCES GOING.

A COLD FRONT WILL PUSH INTO THE STATE ON MONDAY AND WILL BRING A
GOOD CHANCE FOR THUNDERSTORMS BY THE AFTERNOON HOURS. HAVE REMOVED
POPS FROM TUESDAY. ANOTHER SYSTEM WILL DEVELOP ACROSS THE REGION
WEDNESDAY WITH ANOTHER BOUNDARY STALLING ACROSS THE CENTRAL PLAINS.
MUCH BETTER SHEAR PROFILES LOOK TO BE IN PLACE WITH THIS SYSTEM AND
AT THIS TIME APPEARS WILL BRING THE BEST CHANCE FOR SEVERE WEATHER
TO THE FORECAST AREA WEDNESDAY AND THURSDAY. TEMPERATURES THROUGH
THE EXTENDED WILL BE WITHIN A FEW DEGREES OF CLIMATOLOGY.

&&

.DMX WATCHES/WARNINGS/ADVISORIES...NONE

&&

DONAVON

Hazardous weather outlook, May 6, 3:10 PM CDT, 8 hours 16 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
310 PM CDT FRI MAY 6 2005

IAZ004>006-015-016-023>025-033>035-044>046-057-058-070-071100-
EMMET-KOSSUTH-WINNEBAGO-PALO ALTO-HANCOCK-POCAHONTAS-HUMBOLDT-
WRIGHT-SAC-CALHOUN-WEBSTER-CRAWFORD-CARROLL-GREENE-AUDUBON-
GUTHRIE-CASS-
310 PM CDT FRI MAY 6 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL
INTO NORTH CENTRAL IOWA.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS DEVELOP THIS EVENING AND WILL INCREASE IN
AREAL COVERAGE AFTER 1000 PM. A FEW STORMS MAY BECOME
SEVERE...PRODUCING LARGE HAIL AND WIND GUSTS ABOVE 55 MPH FROM 10
PM UNTIL 4 AM.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SEVERAL CHANCES FOR THUNDERSTORMS EXIST FROM SATURDAY THROUGH NEXT
THURSDAY. SOME SEVERE STORMS WILL BE POSSIBLE WITH THE BEST CHANCE
EXPECTED SUNDAY NIGHT...AND AGAIN WEDNESDAY AFTERNOON INTO EARLY THURSDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE FROM 10 PM TONIGHT UNTIL 4 AM
SATURDAY. SPOTTER ACTIVATION IS ALSO POSSIBLE SUNDAY NIGHT AND
AGAIN WEDNESDAY NIGHT.

IAZ007-017-026>028-036>039-047>050-059>062-071>075-081>086-
092>097-071100-
WORTH-CERRO GORDO-FRANKLIN-BUTLER-BREMER-HAMILTON-HARDIN-GRUNDY-
BLACK HAWK-BOONE-STORY-MARSHALL-TAMA-DALLAS-POLK-JASPER-POWESHIEK-
ADAIR-MADISON-WARREN-MARION-MAHASKA-ADAMS-UNION-CLARKE-LUCAS-
MONROE-WAPELLO-TAYLOR-RINGGOLD-DECATUR-WAYNE-APPANOOSE-DAVIS-
310 PM CDT FRI MAY 6 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL IOWA...
SOUTHEAST IOWA...SOUTH CENTRAL IOWA...NORTH CENTRAL IOWA...
SOUTHWEST IOWA AND NORTHEAST IOWA.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER MIDNIGHT
TONIGHT. AT THIS TIME...IT DOES NOT APPEAR LIKELY THAT THE STORMS
WILL BE SEVERE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SEVERAL CHANCES FOR THUNDERSTORMS EXIST FROM SATURDAY THROUGH NEXT
THURSDAY. SOME SEVERE STORMS WILL BE POSSIBLE WITH THE BEST CHANCE
EXPECTED SUNDAY NIGHT...AND AGAIN WEDNESDAY AFTERNOON INTO EARLY THURSDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS POSSIBLE SUNDAY NIGHT AND AGAIN WEDNESDAY
NIGHT.

In the hours before

Local storm report, May 6, 8:18 PM CDT, 3 hours 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
818 PM CDT FRI MAY 06 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0816 PM     HAIL             4 S ARCADIA             42.03N 95.04W
05/06/2005  0.88 INCH        CARROLL            IA   LAW ENFORCEMENT

&&

BF

Local storm report, May 6, 9:37 PM CDT, 1 hour 49 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
937 PM CDT FRI MAY 06 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0926 PM     HAIL             1 S JOLLEY              42.46N 94.72W
05/06/2005  1.00 INCH        CALHOUN            IA   BROADCAST MEDIA

            REPORT FROM KCCI SPOTTER.

&&

BF

Local storm report, May 6, 9:45 PM CDT, 1 hour 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
945 PM CDT FRI MAY 06 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0925 PM     HAIL             3 E JOLLEY              42.48N 94.66W
05/06/2005  1.25 INCH        CALHOUN            IA   TRAINED SPOTTER

            HAIL ON GROUND 2 INCHES DEEP.

&&

BF

Local storm report, May 6, 10:47 PM CDT, 39 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1047 PM CDT FRI MAY 06 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1030 PM     HAIL             HUMBOLDT                42.72N 94.22W
05/06/2005  0.88 INCH        HUMBOLDT           IA   TRAINED SPOTTER

1037 PM     HAIL             3 SW MANSON             42.50N 94.58W
05/06/2005  0.88 INCH        CALHOUN            IA   TRAINED SPOTTER

            AT TWIN LAKES.

1040 PM     HAIL             MANSON                  42.53N 94.54W
05/06/2005  1.00 INCH        CALHOUN            IA   LAW ENFORCEMENT

&&

BF

Local storm report, May 6, 11:08 PM CDT, 18 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1108 PM CDT FRI MAY 06 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1040 PM     HAIL             HUMBOLDT                42.72N 94.22W
05/06/2005  0.75 INCH        HUMBOLDT           IA   LAW ENFORCEMENT

1045 PM     HAIL             HARDY                   42.81N 94.05W
05/06/2005  0.75 INCH        HUMBOLDT           IA   LAW ENFORCEMENT

&&

BF

Local storm report, May 6, 11:11 PM CDT, 15 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1111 PM CDT FRI MAY 06 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1100 PM     HAIL             MANSON                  42.53N 94.54W
05/06/2005  1.25 INCH        CALHOUN            IA   BROADCAST MEDIA

            KCCI SPOTTER.

&&

BF

The office that day

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

Issued	Product	Office	Counties	Lasted
May 6, 8:08 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	52 min
May 6, 9:12 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun	49 min
May 6, 10:33 PM CDT	Severe Thunderstorm Warning	DMX	Humboldt	42 min
May 6, 10:36 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Webster	39 min
May 7, 4:06 AM CDT	Flash Flood Warning	DMX	Hancock, Kossuth	6 hr

Nearby

Severe Thunderstorm Warnings in Iowa, 2005 Every severe thunderstorm warning in 2005

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.