Alert archive / Iowa / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 99, NWS Des Moines, IA

July 2, 1999Madison County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 2, 1999, 4:05 PM CDT for Madison County, Iowa. It was in force for 35 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 2, 1999, 4:05 PM CDT (21:05 UTC)
Expired: Jul 2, 1999, 4:40 PM CDT
In force: 35 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Madison County, IA

The watch it was issued in

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

Issued	Product	Office	Lasted
Jul 2, 12:15 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.1 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: 217 J/kg
Mixed-layer CIN: -357 J/kg
Mixed-layer LCL: 1083 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 171 m²/s²
0-3 km storm-relative helicity: 406 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 Jul 2, 3:45 PM CDT, 20 minutes earlier.

Area forecast discussion, Jul 2, 3:45 PM CDT, 20 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
345 PM CDT FRI JUL 2 1999

THUNDERSTORM COMPLEX CURRENTLY WORKING ITS WAY ACROSS CENTRAL IOWA
WITH THE STRONGEST STORMS LOCATED IN SOUTHERN DALLAS AND WEBSTER
COUNTIES. THUNDERSTORM PROPAGATING TO THE SOUTHEAST INTO UNSTABLE
ATMOS. LOW LEVEL SHEAR WILL HELP KEEP SOME THUNDERSTORM SEVERE.
CAPPING OVER SOUTHEAST SECTION OF THE DES MOINES FORECAST AREA IS
RELATIVELY WEAK WITH CAPPING STRONGER OVER THE REMAINDER OF THE
FORECAST AREA. DALLAS COUNTY STORM IS MOVING ALONG OR JUST TO THE
NORTH OF THE WARM FRONTAL BOUNDARY. 850 MB WARM FRONT OVER CENTRAL
SECTION OF THE STATE. THINKING ACTIVITY NORTH OF THE WARM WILL
CONTINUE UNDER THE LOW LEVEL WARM ADVECTION AND LIFT OVER THE FRONT.
THIS IS THE REASON FOR THE HIGHER POPS IN NORTHERN SECTIONS OF THE
FORECAST AREA. WARM FRONT CONTINUES TO LIFT NORTH TONIGHT SHIFTING
THE THREAT NORTHWARD INTO SOUTHERN MINNESOTA.  WARM ADVECTION
CONTINUES SATURDAY...QUICKLY STRENGTHENING THE CAP BY MIDDAY SO THAT
ANY CHANCE OF CONVECTION WILL BE SUPPRESSED.

EXTENDED...
WILL BE HOT AND HUMID SUNDAY AND MONDAY. AS DAVENPORT NOTED A COLD
FRONT ON MONDAY INTO MONDAY NIGHT WILL HELP COOL THE ATMOSPHERE OFF
TUESDAY AND WEDNESDAY. AGREE AS WELL ENOUGH CAPPING AND STABILITY TO
KEEP ANY ACTIVITY SUPPRESSED.

.DSM...NONE

In the hours before

Special weather statement, Jul 2, 11:10 AM CDT, 4 hours 55 minutes before

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-031100-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
1110 AM CDT FRI JUL 2 1999

HAZARD--SCATTERED THUNDERSTORMS WITH A FEW SEVERE THUNDERSTORMS
CAPABLE OF PRODUCING UP TO TWO INCH HAIL AND WIND GUSTS TO 65 MPH.
SOME OF THE SEVERE THUNDERSTORMS COULD PRODUCE A TORNADO.

AREA OF CONCERN AND TIMING DETAILS--ALONG AND SOUTH OF HIGHWAY 20
AND WEST OF INTERSTATE 35 REMAINDER OF THE MORNING AND THIS
AFTERNOON.  ALL OF FORECAST AREA FROM 900 PM TONIGHT TO 600 AM
SATURDAY MORNING.

METEOROLOGICAL COMMENTS--A THUNDERSTORM COMPLEX WILL MOVE ACROSS
SOUTHWEST IOWA.  STORMS WITHIN THIS SYSTEM WILL CONTINUE TO MAINTAIN
THEIR STRENGTH AS THEY MOVE INTO A MOIST AND UNSTABLE AIRMASS IN
PLACE OVER SOUTHWEST IOWA. BY THIS AFTERNOON...A WARM FRONT WILL BE
MOVING NORTH ACROSS THE STATE.  WARMER AIR AND AN INCREASE IN
MOISTURE WILL INCREASE INSTABILITY ACROSS THE FORECAST AREA.
ANOTHER COMPLEX OF THUNDERSTORMS IS EXPECTED TO DEVELOP ACROSS SOUTH
DAKOTA AND NEBRASKA OVERNIGHT AND MOVE EAST INTO IOWA.  WITH
MODERATE INSTABILITY IN PLACE...A FEW STORMS OVERNIGHT MAY PRODUCE
HAIL UP TO ONE AND A HALF INCHES IN DIAMETER AS WELL AS WIND GUSTS
APPROACHING 65 MPH.  A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL
300 PM THIS AFTERNOON.

PRECAUTION--SPOTTER ACTIVATION WILL BE NEEDED FOR THE REMAINDER OF
THE MORNING AND THIS AFTERNOON SOUTH OF HIGHWAY 20 AND WEST OF
INTERSTATE 35. ACTIVATION MAY ONCE AGAIN BE NEEDED BY THIS EVENING
AND INTO THE OVERNIGHT.  CONTINUE TO MONITOR THE SITUATION AS
CONDITIONS MAY CHANGE AS THIS SYSTEM EVOLVES.

TC

Special weather statement, Jul 2, 11:10 AM CDT, 4 hours 55 minutes before

IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-031100-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
1110 AM CDT FRI JUL 2 1999

HAZARD--SCATTERED THUNDERSTORMS WITH A FEW SEVERE THUNDERSTORMS
CAPABLE OF PRODUCING UP TO TWO INCH HAIL AND WIND GUSTS TO 65 MPH.
SOME OF THE SEVERE THUNDERSTORMS COULD PRODUCE A TORNADO.

AREA OF CONCERN AND TIMING DETAILS--ALONG AND SOUTH OF HIGHWAY 20
AND WEST OF INTERSTATE 35 REMAINDER OF THE MORNING AND THIS
AFTERNOON.  ALL OF FORECAST AREA FROM 900 PM TONIGHT TO 600 AM
SATURDAY MORNING.

METEOROLOGICAL COMMENTS--A THUNDERSTORM COMPLEX WILL MOVE ACROSS
SOUTHWEST IOWA.  STORMS WITHIN THIS SYSTEM WILL CONTINUE TO MAINTAIN
THEIR STRENGTH AS THEY MOVE INTO A MOIST AND UNSTABLE AIRMASS IN
PLACE OVER SOUTHWEST IOWA. BY THIS AFTERNOON...A WARM FRONT WILL BE
MOVING NORTH ACROSS THE STATE.  WARMER AIR AND AN INCREASE IN
MOISTURE WILL INCREASE INSTABILITY ACROSS THE FORECAST AREA.
ANOTHER COMPLEX OF THUNDERSTORMS IS EXPECTED TO DEVELOP ACROSS SOUTH
DAKOTA AND NEBRASKA OVERNIGHT AND MOVE EAST INTO IOWA.  WITH
MODERATE INSTABILITY IN PLACE...A FEW STORMS OVERNIGHT MAY PRODUCE
HAIL UP TO ONE AND A HALF INCHES IN DIAMETER AS WELL AS WIND GUSTS
APPROACHING 65 MPH.  A SEVERE THUNDERSTORM WATCH IS IN EFFECT UNTIL
300 PM THIS AFTERNOON.

PRECAUTION--SPOTTER ACTIVATION WILL BE NEEDED FOR THE REMAINDER OF
THE MORNING AND THIS AFTERNOON SOUTH OF HIGHWAY 20 AND WEST OF
INTERSTATE 35. ACTIVATION MAY ONCE AGAIN BE NEEDED BY THIS EVENING
AND INTO THE OVERNIGHT.  CONTINUE TO MONITOR THE SITUATION AS
CONDITIONS MAY CHANGE AS THIS SYSTEM EVOLVES.

TC

Local storm report, Jul 2, 3:27 PM CDT, 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
327 PM CDT FRI JUL 02 1999

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

1119 AM    3 NW DOW CITY             IA    60+ MPH TSTM GUST
07/02/99   CRAWFORD                        TREE LIMBS DOWN

1132 AM    DOW CITY                  IA    1.75 INCH HAIL
07/02/99   CRAWFORD

1132 AM    DOW CITY                  IA    60+ MPH TSTM GUST
07/02/99   CRAWFORD                        TREE DAMAGE

1132 AM    DENISON MUNI ARPT         IA    66 MPH TSTM GUST
07/02/99   CRAWFORD

1137 AM    DENISON                   IA    60+ MPH TSTM GUST
07/02/99   CRAWFORD                        TREE DAMAGE

1137 AM    DENISON                   IA    1 INCH HAIL
07/02/99   CRAWFORD

1204 PM    6 SW CARROLL              IA    1.75 INCH HAIL
07/02/99   CARROLL

1215 PM    10 SW CARROLL             IA    1.75 INCH HAIL
07/02/99   CARROLL

1225 PM    TEMPLETON                 IA    1.25 INCH HAIL
07/02/99   CARROLL

1230 PM    5 NE AUDUBON              IA    1 INCH HAIL
07/02/99   AUDUBON

1251 PM    3 NW BAYARD               IA    1.75 INCH HAIL
07/02/99   GUTHRIE

1256 PM    3 NW BAYARD               IA    1.75 INCH HAIL
07/02/99   GUTHRIE

1256 PM    3 NW BAYARD               IA    2 INCH HAIL
07/02/99   GUTHRIE

0128 PM    JAMAICA                   IA    2 INCH HAIL
07/02/99   GUTHRIE

0138 PM    8 W PERRY                 IA    1.75 INCH HAIL
07/02/99   DALLAS

0148 PM    7 W PERRY                 IA    1 INCH HAIL
07/02/99   DALLAS                          CLOUD ROTATION

0202 PM    10 N AUDUBON              IA    1 INCH HAIL
07/02/99   AUDUBON

0218 PM    5 NW AUDUBON              IA    1 INCH HAIL
07/02/99   AUDUBON

0220 PM    AUDUBON                   IA    1.75 INCH HAIL
07/02/99   AUDUBON

0224 PM    2 E HAMLIN                IA    2 INCH HAIL
07/02/99   AUDUBON

0234 PM    13 W GUTHRIE CENTER       IA    1.75 INCH HAIL
07/02/99   GUTHRIE

0235 PM    2 E HAMLIN                IA    1.75 INCH HAIL
07/02/99   AUDUBON

0242 PM    10 SW GUTHRIE CENTER      IA    2.75 INCH HAIL
07/02/99   GUTHRIE

0247 PM    3 N ADvAIR                 IA    2.75 INCH HAIL
07/02/99   ADAIR

Local storm report, Jul 2, 3:27 PM CDT, 38 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
327 PM CDT FRI JUL 02 1999

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

1119 AM    3 NW DOW CITY             IA    60+ MPH TSTM GUST
07/02/99   CRAWFORD                        TREE LIMBS DOWN

1132 AM    DOW CITY                  IA    1.75 INCH HAIL
07/02/99   CRAWFORD

1132 AM    DOW CITY                  IA    60+ MPH TSTM GUST
07/02/99   CRAWFORD                        TREE DAMAGE

1132 AM    DENISON MUNI ARPT         IA    66 MPH TSTM GUST
07/02/99   CRAWFORD

1137 AM    DENISON                   IA    60+ MPH TSTM GUST
07/02/99   CRAWFORD                        TREE DAMAGE

1137 AM    DENISON                   IA    1 INCH HAIL
07/02/99   CRAWFORD

1204 PM    6 SW CARROLL              IA    1.75 INCH HAIL
07/02/99   CARROLL

1215 PM    10 SW CARROLL             IA    1.75 INCH HAIL
07/02/99   CARROLL

1225 PM    TEMPLETON                 IA    1.25 INCH HAIL
07/02/99   CARROLL

1230 PM    5 NE AUDUBON              IA    1 INCH HAIL
07/02/99   AUDUBON

1251 PM    3 NW BAYARD               IA    1.75 INCH HAIL
07/02/99   GUTHRIE

1256 PM    3 NW BAYARD               IA    1.75 INCH HAIL
07/02/99   GUTHRIE

1256 PM    3 NW BAYARD               IA    2 INCH HAIL
07/02/99   GUTHRIE

0128 PM    JAMAICA                   IA    2 INCH HAIL
07/02/99   GUTHRIE

0138 PM    8 W PERRY                 IA    1.75 INCH HAIL
07/02/99   DALLAS

0148 PM    7 W PERRY                 IA    1 INCH HAIL
07/02/99   DALLAS                          CLOUD ROTATION

0202 PM    10 N AUDUBON              IA    1 INCH HAIL
07/02/99   AUDUBON

0218 PM    5 NW AUDUBON              IA    1 INCH HAIL
07/02/99   AUDUBON

0220 PM    AUDUBON                   IA    1.75 INCH HAIL
07/02/99   AUDUBON

0224 PM    2 E HAMLIN                IA    2 INCH HAIL
07/02/99   AUDUBON

0234 PM    13 W GUTHRIE CENTER       IA    1.75 INCH HAIL
07/02/99   GUTHRIE

0235 PM    2 E HAMLIN                IA    1.75 INCH HAIL
07/02/99   AUDUBON

0242 PM    10 SW GUTHRIE CENTER      IA    2.75 INCH HAIL
07/02/99   GUTHRIE

0247 PM    3 N ADvAIR                 IA    2.75 INCH HAIL
07/02/99   ADAIR

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 2, 10:47 AM CDT	Tornado Warning	DMX	Crawford	48 min
Jul 2, 11:29 AM CDT	Tornado Warning	DMX	Crawford	36 min
Jul 2, 12:01 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	34 min
Jul 2, 12:22 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	33 min
Jul 2, 12:37 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Guthrie	48 min
Jul 2, 12:45 PM CDT	Severe Thunderstorm Warning	DMX	Greene	50 min
Jul 2, 1:22 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	48 min
Jul 2, 1:42 PM CDT	Severe Thunderstorm Warning	DMX	Audubon	48 min
Jul 2, 2:07 PM CDT	Tornado Warning	DMX	Audubon	33 min
Jul 2, 2:28 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	47 min
Jul 2, 3:00 PM CDT	Severe Thunderstorm Warning	DMX	Adair	65 min
Jul 2, 3:10 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun	35 min
Jul 2, 3:16 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	19 min
Jul 2, 3:23 PM CDT	Severe Thunderstorm Warning	DMX	Webster	47 min
Jul 2, 3:29 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Madison	36 min
Jul 2, 4:43 PM CDT	Severe Thunderstorm Warning	DMX	Webster	32 min
Jul 2, 5:12 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton	33 min
Jul 2, 5:21 PM CDT	Severe Thunderstorm Warning	DMX	Boone	34 min
Jul 2, 5:24 PM CDT	Severe Thunderstorm Warning	DMX	Webster	31 min
Jul 2, 5:38 PM CDT	Severe Thunderstorm Warning	DMX	Boone	47 min
Jul 2, 5:46 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton	34 min
Jul 2, 5:57 PM CDT	Severe Thunderstorm Warning	DMX	Story	48 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; the sounding from the Mesonet's radiosonde archive.