Alert archive / Iowa / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 30, NWS Des Moines, IA

May 16, 1999Bremer County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 16, 1999, 12:40 PM CDT for Bremer County, Iowa. It was in force for 65 min. 3 reports 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 16, 1999, 12:40 PM CDT (17:40 UTC)
Expired: May 16, 1999, 1:45 PM CDT
In force: 65 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Bremer County, IA

The radar

The La Crosse radar (KARX), 148 km from the middle of the area, began a volume at 17:42 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
May 16, 12:51 PM CDT	Hail 1.75	Plainfield, IA
May 16, 1:05 PM CDT	Hail 1.75	Plainfield, IA
May 16, 1:50 PM CDT	Hail 1	Sumner, 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 16, 9:45 AM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 5.7 hours before the alert went out and 197 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: 266 J/kg
Mixed-layer CIN: -240 J/kg
Mixed-layer LCL: 780 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 114 m²/s²
0-3 km storm-relative helicity: 138 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 16, 3:45 AM CDT, 8 hours 55 minutes earlier.

Area forecast discussion, May 16, 3:45 AM CDT, 8 hours 55 minutes before

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In the hours before

Local storm report, May 16, 7:20 AM CDT, 5 hours 20 minutes before

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Local storm report, May 16, 9:00 AM CDT, 3 hours 40 minutes before

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Local storm report, May 16, 11:53 AM CDT, 47 minutes before

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Local storm report, May 16, 11:53 AM CDT, 47 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1153 AM CDT SUN MAY 16 1999

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

0915 AM    GRAND JCT                 IA    1.75 INCH HAIL
05/16/99   GREENE

0950 AM    LAKE VIEW                 IA    1.75 INCH HAIL
05/16/99   SAC                             FROM KICD RADIO

1020 AM    STORY CITY                IA    .75 INCH HAIL
05/16/99   STORY                           FROM STORY CO EMEGENCY
                                           MANAGMENT

1030 AM    ROCKWELL CITY             IA    .75 INCH HAIL
05/16/99   CALHOUN                         FROM CALHOUN CO SHERIFF

1030 AM    STORY CITY                IA    .75 INCH HAIL
05/16/99   STORY                           FROM KCCI TV

1032 AM    2 E ROCKWELL CITY         IA    .75 INCH HAIL
05/16/99   CALHOUN                         FROM NWS SPOTTER

1041 AM    BARNUM                    IA    .75 INCH HAIL
05/16/99   WEBSTER                         FROM WEBSTER CO SHERIFF

1054 AM    BARNUM                    IA    .75 INCH HAIL
05/16/99   WEBSTER                         FROM FORT DODGE PD

1102 AM    FT DODGE                  IA    .75 INCH HAIL
05/16/99   WEBSTER                         FROM FORT DODGE PD

1102 AM    FT DODGE                  IA    .75 INCH HAIL
05/16/99   WEBSTER

1103 AM    RADCLIFFE                 IA    1.75 INCH HAIL
05/16/99   HARDIN                          FROM HARDIN CO SHERIFF

1105 AM    FT DODGE                  IA    1 INCH HAIL
05/16/99   WEBSTER                         FROM NWS SPOTTER

1105 AM    RADCLIFFE                 IA    .75 INCH HAIL
05/16/99   HARDIN                          FROM NWS SPOTTER

1110 AM    FT DODGE                  IA    1.75 INCH HAIL
05/16/99   WEBSTER                         AROUND 10 MINUTES OF
                                           GOLF BALL SIZED HAIL.
                                           FROM OFF-DUTY NWS
                                           EMPLOYEE.

1111 AM    FT DODGE                  IA    1.75 INCH HAIL
05/16/99   WEBSTER                         FROM KCCI TV

1116 AM    FT DODGE                  IA    1.75 INCH HAIL
05/16/99   WEBSTER                         FROM KCCI TV

1127 AM    3 SE IOWA FALLS           IA    .75 INCH HAIL
05/16/99   HARDIN                          FROM NWS SPOTTER

1129 AM    EAGLE GROVE               IA    1 INCH HAIL
05/16/99   WRIGHT                          FROM KCCI TV

1145 AM    WOOLSTOCK                 IA    .75 INCH HAIL
05/16/99   WRIGHT                          FROM WRIGHT CO SHERIFF

SMALL

Special weather statement, May 16, 12:13 PM CDT, 27 minutes before

IAZ004-005-015-023-024-033>035-044>049-057>062-070>075-081>086-
092>097-161800-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1213 PM CDT SUN MAY 16 1999

...THE SEVERE THUNDERSTORM WATCH HAS BEEN CANCELED FOR MUCH OF THE
SOUTHWEST HALF OF IOWA...

SEVERE THUNDERSTORM WATCH NUMBER 270 HAS BEEN CANCELED ALONG AND
WEST OF AN ALGONA...TO BOONE...TO MARSHALLTOWN...TO OTTUMWA LINE.
THE CITIES OF DENISON...FORT DODGE...AMES...DES MOINES...ATLANTIC...
CRESTON...CHARITON AND OTTUMWA ARE NO LONGER UNDER A WATCH.

HOWEVER MASON CITY...WATERLOO...CEDAR FALLS...WEBSTER CITY AND
SURROUNDING AREAS REMAIN UNDER THE WATCH UNTIL 300 PM.

PEOPLE IN THE WATCH CLEARANCE AREA SHOULD LISTEN FOR LATER
STATEMENTS FROM THE NATIONAL WEATHER SERVICE.  THE ATMOSPHERE REMAINS
VERY UNSTABLE AND SEVERE THUNDERSTORMS MAY REDEVELOP LATER THIS
AFTERNOON.  ADDITIONAL WATCHES WILL LIKELY BE ISSUED.

SMALL

Special weather statement, May 16, 12:15 PM CDT, 25 minutes before

IAZ017-018-026-027-161730-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1215 PM CDT SUN MAY 16 1999

...SEVERE THUNDERSTORM WARNING UNTIL 1245 PM FOR FRANKLIN COUNTY...

AT 1215 PM A SEVERE THUNDERSTORM WAS LOCATED ACROSS MUCH OF FRANKLIN
COUNTY. QUARTER SIZE HAIL WAS REPORTED IN HAMPTON. THE STORM
CONTINUES TO MOVE TO THE EAST NORTHEAST AT 30 MPH.

The office that day

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

Issued	Product	Office	Counties	Lasted
May 16, 3:52 AM CDT	Severe Thunderstorm Warning	DMX	Clarke	33 min
May 16, 4:09 AM CDT	Severe Thunderstorm Warning	DMX	Warren	36 min
May 16, 8:47 AM CDT	Severe Thunderstorm Warning	DMX	Greene	33 min
May 16, 9:19 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Greene	36 min
May 16, 9:24 AM CDT	Severe Thunderstorm Warning	DMX	Sac	41 min
May 16, 10:12 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Story	33 min
May 16, 10:28 AM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Webster	32 min
May 16, 10:47 AM CDT	Severe Thunderstorm Warning	DMX	Hamilton, Hardin	33 min
May 16, 10:58 AM CDT	Severe Thunderstorm Warning	DMX	Webster	32 min
May 16, 11:18 AM CDT	Severe Thunderstorm Warning	DMX	Hardin	32 min
May 16, 11:23 AM CDT	Severe Thunderstorm Warning	DMX	Hamilton, Wright	47 min
May 16, 12:00 PM CDT	Severe Thunderstorm Warning	DMX	Franklin	45 min
May 16, 12:27 PM CDT	Severe Thunderstorm Warning	DMX	Butler	63 min
May 16, 12:46 PM CDT	Severe Thunderstorm Warning	DMX	Franklin	34 min
May 16, 1:28 PM CDT	Severe Thunderstorm Warning	DMX	Butler	32 min
May 16, 1:43 PM CDT	Severe Thunderstorm Warning	DMX	Bremer	62 min
May 16, 2:18 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk	47 min
May 16, 3:42 PM CDT	Tornado Warning	DMX	Crawford	33 min
May 16, 4:13 PM CDT	Tornado Warning	DMX	Crawford	17 min
May 16, 4:20 PM CDT	Tornado Warning	DMX	Crawford	50 min
May 16, 4:33 PM CDT	Severe Thunderstorm Warning	DMX	Hardin	32 min
May 16, 4:38 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Grundy	32 min
May 16, 4:43 PM CDT	Tornado Warning	DMX	Sac	47 min
May 16, 5:55 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Bremer	35 min
May 16, 6:13 PM CDT	Severe Thunderstorm Warning	DMX	Cass	32 min
May 16, 6:17 PM CDT	Flash Flood Warning	DMX	Hardin	2 hr
May 16, 6:26 PM CDT	Severe Thunderstorm Warning	DMX	Butler	34 min
May 16, 6:38 PM CDT	Tornado Warning	DMX	Audubon, Cass	47 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1999 Every severe thunderstorm warning in 1999

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; radar from the NEXRAD Level II archive.