Alert archive / Iowa / Tornado Warnings in 1998

Tornado Warning 12, NWS Des Moines, IA

May 15, 1998Calhoun County, Pocahontas County, Iowa

NWS Des Moines, IA issued this tornado warning at May 15, 1998, 4:24 PM CDT for Calhoun County, Pocahontas County, Iowa. It was in force for 36 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: May 15, 1998, 4:24 PM CDT (21:24 UTC)
Expired: May 15, 1998, 5:00 PM CDT
In force: 36 min
Issued by: NWS Des Moines, IA
Area: Whole counties

Counties Calhoun County, IA, Pocahontas County, IA

What was reported inside it

Time	Report	Where	Remark
May 15, 4:43 PM CDT	Thunderstorm Wind 61	Pocahontas, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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 15, 3:00 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.4 hours before the alert went out and 198 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: 1194 J/kg
Mixed-layer CIN: -370 J/kg
Mixed-layer LCL: 1627 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: -76 m²/s²
0-3 km storm-relative helicity: 26 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

790 
WFUS1 KDSM 152125 RRA
TORDSM
IAC025-151-152200-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
424 PM CDT FRI MAY 15 1998

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

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

* UNTIL 500 PM CDT

* AT 424 PM CDT... DOPPLER RADAR INDICATED A TORNADO 22 MILES WEST
  OF FORT DODGE OR 6 MILES SOUTHWEST OF MANSON MOVING NORTH
  NORTHEAST AT 50 MPH.

* THIS TORNADO CAN BE EXPECTED NEAR...
   POMEROY            BY 423 PM CDT
   MANSON             BY 426 PM CDT
   PALMER             BY 431 PM CDT
   ROLFE              BY 446 PM CDT

GO TO THE BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR

GF/BSS

What forecasters said that day

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

In the hours before

Special weather statement, May 15, 11:25 AM CDT, 4 hours 59 minutes before

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-152225-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
1125 AM CDT FRI MAY 15 1998

HAZARD--LINE OF SEVERE STORMS MOVING NORTH INTO FAR NORTHWEST AND
NORTH CENTRAL IOWA WITH DAMAGING WINDS.  ISOLATED TORNADOES AND
LARGE HAIL ARE POSSIBLE AFTER NOON WITH SUPERCELL THUNDERSTORMS.
THE STORM PREDICTION CENTER HAS FORECASTED A MODERATE RISK OF SEVERE
WEATHER IN IOWA.

TIMIMG DETAILS AND AREA OF CONCERN--
THE FIRST LINE OF THUNDERSTORMS IS MOVING NORTH AT 60 MPH AFFECTING
AREAS ALONG AND NORTH OF FORT DODGE TO STORM LAKE THROUGH 100 PM.

IN SOUTHWEST AND SOUTH CENTRAL IOWA...A SEVERE THUNDERSTORM WATCH
CONTINUES UNTIL NOON...BUT FURTHER WATCHES MAY BE REISSUED LATER THIS
AFTERNOON. ADDITIONAL THUNDERSTORMS ARE DEVELOPING SOUTH OF OMAHA
MOVING NORTHEAST.

METEOROLOGICAL COMMENTS--THE SQUALL LINE OVER NORTHWEST INTO NORTH
CENTRAL IOWA WILL RACE NORTH INTO MINNESOTA BY 100 PM.  HOWEVER...
AN UNSTABLE AIRMASS EXISTS OVER SOUTHERN IOWA INTO MISSOURI AND
EASTERN KANSAS.  A POTENT UPPER LEVEL SYSTEM OVER CENTRAL KANSAS
WILL BE MOVING INTO IOWA THIS AFTERNOON.  A STRONG JET STREAM OF 100
MPH OR GREATER WILL BE MOVING NORTHEAST INTO IOWA WITH LOW-LEVEL
WINDS STAYING SOUTH TO SOUTHEAST.  THIS WILL PROVIDE AMPLE WIND
SHEAR TO DEVELOP A FEW SUPERCELLS BEFORE A NEW SQUALL DEVELOPS
ALONG THE DRY LINE. THIS DRY LINE WILL PUNCH INTO WESTERN MISSOURI
AND SOUTHERN IOWA BY 300 PM OR SO.

PRECAUTIONS--SPOTTER ORGANIZATIONS AND EMERGENCY MANAGEMENT SHOULD
PREPARE FOR ADDITIONAL ACTIVATION THIS AFTERNOON.  MAINTAIN A
WATCH FOR ADDITIONAL NWS OUTLOOKS AND SHORT TERM FORECASTS.

KULA

Local storm report, May 15, 11:49 AM CDT, 4 hours 35 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1149 AM CDT FRI MAY 15 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0935 AM    15 SSW ATLANTIC           IA   65 MPH TSTM GUST
05/15/98   CASS

0941 AM    GRISWOLD                  IA   75 MPH TSTM GUST
05/15/98   CASS                           LARGE BRANCHES DOWN

0958 AM    AUDUBON                   IA   WIND DAMAGE
05/15/98   AUDUBON                        POWER OUT...NUMEROUS TREE
                                          BRANCHES DOWN

0958 AM    3 W AUDUBON               IA   WIND DAMAGE
05/15/98   AUDUBON                        BARN BLOWN DOWN...TREES
                                          DOWN

1002 AM    DENISON MUNI ARPT         IA   60 MPH TSTM GUST
05/15/98   CRAWFORD                       DENISON AWOS AUTOMATED
                                          OBSERVATION

1012 AM    3 SE BUCK GROVE           IA   WIND DAMAGE
05/15/98   CRAWFORD                       ROOF TAKEN OFF BARN

1016 AM    CARROLL                   IA   70 MPH TSTM GUST
05/15/98   CARROLL

1019 AM    TEMPLETON                 IA   60 MPH TSTM GUST
05/15/98   CARROLL                        TREES DOWN...POWER OUT
                                          FROM HAM RADIO

1020 AM    DENISON                   IA   WIND DAMAGE
05/15/98   CRAWFORD                       BILLBOARD DOWN WITH DEBRIS

1022 AM    CARROLL NEU ARPT          IA   59 MPH TSTM GUST
05/15/98   CARROLL                        CARROLL AWOS AUTOMATED
                                          OBSERVATION

1032 AM    GLIDDEN                   IA   58 MPH TSTM GUST
05/15/98   CARROLL                        FROM HAM RADIO

SMALL/COGIL

Local storm report, May 15, 11:49 AM CDT, 4 hours 35 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1149 AM CDT FRI MAY 15 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0935 AM    15 SSW ATLANTIC           IA   65 MPH TSTM GUST
05/15/98   CASS

0941 AM    GRISWOLD                  IA   75 MPH TSTM GUST
05/15/98   CASS                           LARGE BRANCHES DOWN

0958 AM    AUDUBON                   IA   WIND DAMAGE
05/15/98   AUDUBON                        POWER OUT...NUMEROUS TREE
                                          BRANCHES DOWN

0958 AM    3 W AUDUBON               IA   WIND DAMAGE
05/15/98   AUDUBON                        BARN BLOWN DOWN...TREES
                                          DOWN

1002 AM    DENISON MUNI ARPT         IA   60 MPH TSTM GUST
05/15/98   CRAWFORD                       DENISON AWOS AUTOMATED
                                          OBSERVATION

1012 AM    3 SE BUCK GROVE           IA   WIND DAMAGE
05/15/98   CRAWFORD                       ROOF TAKEN OFF BARN

1016 AM    CARROLL                   IA   70 MPH TSTM GUST
05/15/98   CARROLL

1019 AM    TEMPLETON                 IA   60 MPH TSTM GUST
05/15/98   CARROLL                        TREES DOWN...POWER OUT
                                          FROM HAM RADIO

1020 AM    DENISON                   IA   WIND DAMAGE
05/15/98   CRAWFORD                       BILLBOARD DOWN WITH DEBRIS

1022 AM    CARROLL NEU ARPT          IA   59 MPH TSTM GUST
05/15/98   CARROLL                        CARROLL AWOS AUTOMATED
                                          OBSERVATION

1032 AM    GLIDDEN                   IA   58 MPH TSTM GUST
05/15/98   CARROLL                        FROM HAM RADIO

SMALL/COGIL

Special weather statement, May 15, 1:24 PM CDT, 3 hours before

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-152324-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
124 PM CDT FRI MAY 15 1998

HAZARD--ISOLATED TORNADOES...LARGE HAIL GREATER THAN 1 INCH AND
STRAIGHT LINE WINDS GREATER THAN 60 MPH.

AREA OF CONCERN AND TIMING DETAILS--ALL OF CENTRAL IOWA...ESPECIALLY
IN AREAS FROM RED OAK NORTHEAST TOWARD CARROLL...FORT DODGE AND MASON
CITY. THEN SPREADING EAST LATE THIS AFTERNOON INTO REST OF AREA.

PRECAUTIONS--SPOTTER ORGANIZATIONS AND EMERGENCY MANAGEMENT SHOULD
PREPARE FOR ACTIVATION THIS AFTERNOON.  MAINTAIN A WATCH FOR
ADDITIONAL NWS OUTLOOKS AND SHORT TERM FORECASTS.  A SEVERE
THUNDERSTORM WATCH REMAINS IN EFFECT FOR MOST OF NORTH CENTRAL AND
NORTHWEST IOWA UNTIL 300 PM.  ADDITIONAL WATCHES MAY BE REQUIRED
THIS AFTERNOON.

KULA

Special weather statement, May 15, 1:24 PM CDT, 3 hours before

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-152324-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
124 PM CDT FRI MAY 15 1998

HAZARD--ISOLATED TORNADOES...LARGE HAIL GREATER THAN 1 INCH AND
STRAIGHT LINE WINDS GREATER THAN 60 MPH.

AREA OF CONCERN AND TIMING DETAILS--ALL OF CENTRAL IOWA...ESPECIALLY
IN AREAS FROM RED OAK NORTHEAST TOWARD CARROLL...FORT DODGE AND MASON
CITY. THEN SPREADING EAST LATE THIS AFTERNOON INTO REST OF AREA.

PRECAUTIONS--SPOTTER ORGANIZATIONS AND EMERGENCY MANAGEMENT SHOULD
PREPARE FOR ACTIVATION THIS AFTERNOON.  MAINTAIN A WATCH FOR
ADDITIONAL NWS OUTLOOKS AND SHORT TERM FORECASTS.  A SEVERE
THUNDERSTORM WATCH REMAINS IN EFFECT FOR MOST OF NORTH CENTRAL AND
NORTHWEST IOWA UNTIL 300 PM.  ADDITIONAL WATCHES MAY BE REQUIRED
THIS AFTERNOON.

KULA

The office that day

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

Issued	Product	Office	Counties	Lasted
May 15, 9:18 AM CDT	Severe Thunderstorm Warning	DMX	Taylor	32 min
May 15, 9:28 AM CDT	Severe Thunderstorm Warning	DMX	Cass	37 min
May 15, 9:46 AM CDT	Severe Thunderstorm Warning	DMX	Audubon	34 min
May 15, 9:54 AM CDT	Severe Thunderstorm Warning	DMX	Crawford	36 min
May 15, 10:00 AM CDT	Severe Thunderstorm Warning	DMX	Carroll	35 min
May 15, 10:11 AM CDT	Tornado Warning	DMX	Crawford	34 min
May 15, 10:16 AM CDT	Severe Thunderstorm Warning	DMX	Sac	34 min
May 15, 10:24 AM CDT	Severe Thunderstorm Warning	DMX	Calhoun	36 min
May 15, 12:56 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	34 min
May 15, 1:04 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Sac	31 min
May 15, 1:09 PM CDT	Tornado Warning	DMX	Calhoun	36 min
May 15, 1:16 PM CDT	Severe Thunderstorm Warning	DMX	Humboldt	34 min
May 15, 1:31 PM CDT	Severe Thunderstorm Warning	DMX	Kossuth	34 min
May 15, 1:38 PM CDT	Tornado Warning	DMX	Kossuth	32 min
May 15, 1:42 PM CDT	Severe Thunderstorm Warning	DMX	Pocahontas	33 min
May 15, 1:48 PM CDT	Severe Thunderstorm Warning	DMX	Cass	17 min
May 15, 1:51 PM CDT	Severe Thunderstorm Warning	DMX	Audubon	34 min
May 15, 2:10 PM CDT	Severe Thunderstorm Warning	DMX	Kossuth	35 min
May 15, 2:38 PM CDT	Tornado Warning	DMX	Kossuth	22 min
May 15, 3:03 PM CDT	Severe Thunderstorm Warning	DMX	Boone, Greene	32 min
May 15, 3:22 PM CDT	Severe Thunderstorm Warning	DMX	Webster	33 min
May 15, 3:29 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton	31 min
May 15, 3:37 PM CDT	Tornado Warning	DMX	Wright	33 min
May 15, 3:42 PM CDT	Severe Thunderstorm Warning	DMX	Story	33 min
May 15, 3:51 PM CDT	Severe Thunderstorm Warning	DMX	Wapello	34 min
May 15, 3:54 PM CDT	Severe Thunderstorm Warning	DMX	Sac	36 min
May 15, 3:59 PM CDT	Severe Thunderstorm Warning	DMX	Franklin, Hardin	46 min
May 15, 3:59 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo, Hancock	46 min
May 15, 4:09 PM CDT	Severe Thunderstorm Warning	DMX	Davis	36 min
May 15, 4:13 PM CDT	Tornado Warning	DMX	Wapello	32 min
May 15, 4:40 PM CDT	Severe Thunderstorm Warning	DMX	Humboldt	35 min
May 15, 4:45 PM CDT	Severe Thunderstorm Warning	DMX	Tama	35 min
May 15, 4:48 PM CDT	Severe Thunderstorm Warning	DMX	Kossuth, Palo Alto	47 min
May 15, 4:59 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Grundy	31 min
May 15, 5:00 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk	35 min
May 15, 5:07 PM CDT	Severe Thunderstorm Warning	DMX	Bremer	33 min
May 15, 5:40 PM CDT	Severe Thunderstorm Warning	DMX	Bremer	35 min

Nearby

Tornado Warnings in Iowa, 1998 Every tornado warning in 1998 Tornadoes in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.