Alert archive / Iowa / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 153, NWS Des Moines, IA

July 10, 2002Wayne County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 10, 2002, 8:50 AM CDT for Wayne County, Iowa. It was in force for 55 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: Jul 10, 2002, 8:50 AM CDT (13:50 UTC)
Expired: Jul 10, 2002, 9:45 AM CDT
In force: 55 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Wayne County, IA

The radar

The Des Moines radar (KDMX), 110 km from the middle of the area, began a volume at 13:49 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 watch it was issued in

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

Issued	Product	Office	Lasted
Jul 10, 7:30 AM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 1.8 hours before the alert went out and 258 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: 2510 J/kg
Mixed-layer CIN: -226 J/kg
Mixed-layer LCL: 1131 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: -40 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

516 
WUUS53 KDMX 101350
SVRDSM
IAC185-101445-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
850 AM CDT WED JUL 10 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WAYNE COUNTY IN SOUTH CENTRAL IOWA

* UNTIL 945 AM CDT

* AT 844 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE
  OF SEVERE THUNDERSTORMS FROM 21 MILES NORTH OF HUMESTON TO 26 MILES
  WEST OF HUMESTON...OR FROM 32 MILES SOUTH OF DES MOINES TO 62 MILES
  SOUTH OF DES MOINES...MOVING SOUTHEAST AT 30 MPH.

* SEVERE THUNDERSTORMS WILL BE...

  NEAR HUMESTON AROUND 855 AM...
  NEAR MILLERTON AROUND 910 AM...
  NEAR CORYDON AROUND 915 AM...
  NEAR CLIO AROUND 920 AM...
  NEAR PROMISE CITY AROUND 930 AM AND
  NEAR SEYMOUR AROUND 935 AM.

DAMAGING WINDS OF 60 TO 70 MILES AN HOUR ARE LIKELY IN THE WARNED
AREA.

MOVE TO AN INTERIOR ROOM AND STAY AWAY FROM WINDOWS. IF YOU LIVE IN A
MOBILE HOME...SEEK SHELTER IN A STURDY BUILDING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL NOON WEDNESDAY
FOR SOUTHWESTERN IOWA.

LAT...LON 4090 9355 4059 9356 4059 9312 4089 9311

JUNGBLUTH

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 10, 2:13 AM CDT, 6 hours 37 minutes earlier.

Area forecast discussion, Jul 10, 2:13 AM CDT, 6 hours 37 minutes before

AREA FORECAST DISCUSSION...CORRECTED 1ST PARA
NATIONAL WEATHER SERVICE DES MOINES IA
213 AM CDT WED JUL 10 2002

TODAY AND TONIGHT...
BUSY DAY AND NIGHT AHEAD WITH VERY DYNAMIC SYSTEM FOR JULY PUSHING
INTO VERY JUICED AIRMASS.  APPEARS WELL BE DEALING WITH TWO MORNING
MCSS NOW WITH NEW DEVELOPMENT OVER AND SW OF FSD.  IN FACT, APPEARS
TO BE RIGHT MOVING HP SUPERCELL TO BE DEVELOPING JUST SW OF YKN,
DEPICTING THE AMOUNT OF WATER AND CAPE STILL AVAILABLE.  PRECIP
LOADING LIKELY THE TROUBLE MAKER HERE FOR WET MACROBURST ACTIVITY AS
NOTED BY SLB OB OF 52KT EARLIER.  SHEAR INCREASES THROUGH THE DAY AS
UPPER LOW APPROACHES.  FORCING WILL LIKELY COME THROUGH QG PROCESSES
WITH CONVECTION LIKELY LIMITING THERMODYNAMICS A BIT.  FIRST MCS IS
NOW PROPOGATING MORE IN LINE WITH CORFIDI VECTORS WITH A BEELINE FOR
THE CENTRAL AND EVENTUALLY SOUTHERN CWA.  WILL GO WITH CATEGORICAL
HIGH POPS GIVEN RADAR TRENDS AS I BELIEVE THE MCS SHOULD MAINTAIN
ITSELF THROUGH 20KT+ STORM RELATIVE INFLOW WHILE MOVING INTO LOW
LEVEL THETA E RIDGE.  SURFACE DEW POINT POOL AOA 72F NOW IN PLACE
OVER IA.  PWATS STAY AOA 1.75 INCHES THROUGH TONIGHT, WITH LOCAL
AREAS ABOVE 2 INCHES.  STRONG JULY Q-VECTOR CONVERGENCE THROUGH
TONIGHT WITH SLOW MOVING UPPER LOW.  DEEP AVN STILL THE WAY TO GO,
BUT WILL SIDE WITH HEAVIER QPF IN LINE WITH LATEST EXCESSIVE RAIN
OUTLOOK.  AS SYSTEM DROPS S THROUGH IA, DEFORMATION OVER A CORRIDOR
IN CENTRAL AND SOUTHERN IA MAY REALLY ADD UP THE RAIN AMOUNTS LATER
TONIGHT.  META QUITE OMINOUS ON THIS QPF, ESPECIALLY S AND SW OF DSM
AREA.  THIS COULD CONCEIVABLY SETUP NEARLY ANYWHERE TONIGHT THOUGH
DEPENDING ON MESOSCALE BOUNDARY INTERACTIONS THAT PLAY A ROLE.
ANTECEDANT FFG VALUES ARE RATHER HIGH IN OUR NW CWA, BUT THIS
MORNINGS RAINFALL SHOULD LOWER THESE.  CENTRAL AND EAST CENTRAL
COUNTIES ARE MOST SUSEPTIBLE BASED ON RECENT RAINS.  IN EITHER CASE,
THIS SYSTEM COULD LEAD TO FLOOD CONDITIONS AS OPPOSED TO FLASH FLOOD
WITH LOCAL AREAS RECEIVING 4+ INCHES.  EVENING SHIFT MADE A GOOD
CALL ON ADDING HEAVY RAIN TO FORECAST.  A FLOOD WATCH WILL BE
HOISTED FOR THE ENTIRE CWA THIS AFTERNOON AND TONIGHT.  FOR TEMPS, I
HAVE FOLLOWED CLOSE TO FWC VALUES FOR TODAY AND TONIGHT.

THURSDAY INTO FRIDAY...
DEFORMATION ZONE MAY STILL BE PLAYING HAVOC IN SOUTHERN IA THURSDAY
MORNING, WITH THE POTENTIAL FOR LONG LIVED HEAVY RAIN EVENT
PERSISTING THROUGH EARLY PART OF THE DAY.  TEMPS ARE A CHALLENGE
GIVEN LARGE DESPARITY.  ENE FLOW SHOULD DRY THINGS OUT WELL IN NE
IA, AND THATS WHERE THE WARMEST TEMPS MAY END UP WHILE RAIN AND
CLOUDS RESIDE IN THE S AND W IA.  HAVE GONE WITH ETA TEMPS WHICH ARE
A GOOD COMPROMISE, AND MORE REASONABLE THAN THE COOL (AVN) AND WARM
(FWC).

.DSM...FLOOD WATCH THIS AFTERNOON AND TONIGHT ENTIRE DMX CWA.

KULA

In the hours before

Local storm report, Jul 10, 7:31 AM CDT, 1 hour 19 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
731 AM CDT WED JUL 10 2002

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

0728 AM    PANORA                    IA   77 MPH TSTM GUST
07/10/02   GUTHRIE                        REPORTED BY KCCI-TV
                                          SCHOOL NET SITE.

Local storm report, Jul 10, 7:42 AM CDT, 1 hour 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
742 AM CDT WED JUL 10 2002

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

0738 AM    PANORA                    IA   70 MPH TSTM GUST
07/10/02   GUTHRIE                        TREES BLOWN DOWN.
                                          REPORTED BY STORM
                                          SPOTTER.

Local storm report, Jul 10, 7:57 AM CDT, 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
757 AM CDT WED JUL 10 2002

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

0755 AM    1 SW PERRY                IA   65 MPH TSTM GUST
07/10/02   DALLAS                         CORN CROP DAMAGE  SMALL
                                          TREES DOWN. REPORTED BY
                                          STORM SPOTTER.
                                          REPORTED TO EMER
                                          MANAGEMENT FROM STORM
                                          SPOTTER

Local storm report, Jul 10, 8:19 AM CDT, 31 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
819 AM CDT WED JUL 10 2002

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

0758 AM    12 W WINTERSET            IA   70 MPH TSTM GUST
07/10/02   MADISON                        SEMI OVERTURNED HWY 92
                                          GRAIN BIN DOWN MADISON
                                          / ADAIR CO LINE
                                          NUMEROUS TREES DOWN

0758 AM    WAUKEE                    IA   60 MPH TSTM GUST
07/10/02   DALLAS

0809 AM    (DSM)DES MOINES INTL ARPT IA   60 MPH TSTM GUST
07/10/02   POLK                           DES MOINES ASOS

Local storm report, Jul 10, 8:30 AM CDT, 20 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
830 AM CDT WED JUL 10 2002

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

0704 AM    CARROLL                   IA   WIND DAMAGE
07/10/02   CARROLL                        NUMEROUS TREES AND
                                          POWER POLES DOWN.
                                          REPORTED BY EMERGENCY
                                          MANAGEMENT.

Local storm report, Jul 10, 8:48 AM CDT, 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
848 AM CDT WED JUL 10 2002

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

0820 AM    1 S NORWALK               IA   WIND DAMAGE
07/10/02   WARREN                         TREES AND POWER LINES
                                          DOWN. REPORTED BY LAW
                                          ENFORCEMENT OFFICIAL.

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 1:35 AM CDT	Severe Thunderstorm Warning	DMX	Sac	40 min
Jul 10, 4:23 AM CDT	Severe Thunderstorm Warning	DMX	Story	27 min
Jul 10, 6:11 AM CDT	Severe Thunderstorm Warning	DMX	Crawford	49 min
Jul 10, 6:28 AM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Sac	62 min
Jul 10, 6:52 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Guthrie	53 min
Jul 10, 7:10 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Guthrie	35 min
Jul 10, 7:13 AM CDT	Severe Thunderstorm Warning	DMX	Greene, Guthrie	62 min
Jul 10, 7:22 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Dallas	53 min
Jul 10, 7:31 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Cass	29 min
Jul 10, 7:44 AM CDT	Severe Thunderstorm Warning	DMX	Polk	46 min
Jul 10, 7:50 AM CDT	Severe Thunderstorm Warning	DMX	Madison	40 min
Jul 10, 8:05 AM CDT	Severe Thunderstorm Warning	DMX	Clarke, Warren	55 min
Jul 10, 8:12 AM CDT	Severe Thunderstorm Warning	DMX	Union	33 min
Jul 10, 8:15 AM CDT	Severe Thunderstorm Warning	DMX	Madison, Polk	15 min
Jul 10, 8:16 AM CDT	Severe Thunderstorm Warning	DMX	Clarke, Warren	44 min
Jul 10, 8:17 AM CDT	Severe Thunderstorm Warning	DMX	Union	28 min
Jul 10, 8:29 AM CDT	Severe Thunderstorm Warning	DMX	Decatur, Ringgold	46 min
Jul 10, 8:36 AM CDT	Severe Thunderstorm Warning	DMX	Lucas	39 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2002 Every severe thunderstorm warning in 2002

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.