Alert archive / Iowa / Severe Thunderstorm Warnings in 2003
Severe Thunderstorm Warning 223, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 31, 2003, 4:59 PM CDT for Black Hawk County, Iowa. It was in force for 31 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 31, 2003, 4:59 PM CDT (21:59 UTC)
- Expired
- Jul 31, 2003, 5:30 PM CDT
- In force
- 31 min
- Issued by
- NWS Des Moines, IA
- Area
- Counties, with a storm outline in the text
County Black Hawk County, IA
The radar
The Des Moines radar (KDMX), 143 km from the middle of the area, began a volume at 22:01 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.
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 31, 12:00 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 10.0 hours before the alert went out and 177 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.
- Mixed-layer CAPE
- 51 J/kg
- Mixed-layer CIN
- -90 J/kg
- Mixed-layer LCL
- 1404 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 35 m²/s²
- 0-3 km storm-relative helicity
- 61 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 31, 3:05 PM CDT, 1 hour 54 minutes earlier.
Area forecast discussion, Jul 31, 3:05 PM CDT, 1 hour 54 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 305 PM CDT THU JUL 31 2003 STTN WITH CDFNT DVLPG ABT AS SELS INDICTD IN LATEST SWODY1 AND WUD NOT BE SURPRISED TO SEE SLGT AREA BKN INTO TWO WITH IA SPLIT OUT FOT THE MOST PART IN NXT UPDT. BEST SHOT OVR NERN IA AND WL CARRY LKLY POPS IN CUR WATCH AREA. CHC ELSW, BUT XPCT PCPN MST ACTVTY TO ONLY BRUSH SWRN ZNS. SYS DPCTD INIT ON 06Z CHTS WL BRUSH SRN IA FRI. ONLY OTR PCPN IN FCST WL BE CYC CRCLN AFTN SHWRS OVR THE NERN ZNS. IA CAUGHT IN BLOCK AFT THAT THRU DAY 7 WITH TEMPS MODERATING SLOWLY AND NO SIG WX. SHAVED TEMPS THUT FCST A FEW DEG WITH ALL MDLS SHOWING COLDER AIR WORKING IN ARND UPR LO. .DSM...NONE
Hazardous weather outlook, Jul 31, 12:05 PM CDT, 4 hours 54 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086- 092>097-011100- HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE DES MOINES IA 1205 PM CDT THU JUL 31 2003 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL IOWA. .DAY ONE...TODAY AND TONIGHT A COLD FRONT WILL PUSH ACROSS CENTRAL IOWA THIS AFTERNOON AND TONIGHT. THUNDERSTORMS ARE FORECAST TO DEVELOP ALONG AND AHEAD OF THIS FRONT AFTER NOON. A FEW STORMS MAY BECOME SEVERE THIS AFTERNOON AND EVENING. LARGE HAIL AND DAMAGING WIND WILL BE THE MAIN THREAT. THE POTENTIAL DOES EXIST FOR AN ISOLATED SUPERCELL THUNDERSTORM THAT COULD PRODUCE A TORNADO...MAINLY EAST OF I-35. ADDITIONAL THUNDERSTORMS ARE POSSIBLE DURING THE OVERNIGHT HOURS BUT THE SEVERE POTENTIAL WILL DIMINISH AFTER MIDNIGHT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY A LARGE AREA OF LOW PRESSURE NEAR THE MINNESOTA AND CANADIAN BORDER WILL SINK INTO WISCONSIN FRIDAY WHERE IT WILL MOVE VERY LITTLE FOR THE NEXT THREE DAYS. DISTURBANCES ROTATING AROUND THIS LOW WILL BRING ADDITIONAL CHANCES FOR THUNDERSTORMS ON FRIDAY ACROSS THE SOUTHEAST PORTION OF CENTRAL IOWA. ON SATURDAY YET ANOTHER DISTURBANCE WILL BRING A CHANCE FOR THUNDERSTORMS TO NORTHEAST PARTS OF CENTRAL IOWA. TIMING DETAILS ARE NOT CLEAR THOUGH THE AFTERNOON AND EVENING HOURS APPEAR TO BE THE BEST TIME FOR THE DEVELOPMENT OF THE STORMS FOR FRIDAY AND SATURDAY. LARGE HAIL AND DAMAGING WIND WOULD BE THE MAIN THREATS FROM THESE STORMS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS POSSIBLE THIS AFTERNOON THROUGH MIDNIGHT. SPOTTERS MAY ONCE AGAIN BE NEEDED FRIDAY AFTERNOON MAINLY EAST OF I-35 AND SOUTH OF HIGHWAY 20. && MORE INFORMATION CAN BE OBTAINED AT WWW.CRH.NOAA.GOV/DMX (ALL LOWER CASE). FORSTER
Nearby
Severe Thunderstorm Warnings in Iowa, 2003Every severe thunderstorm warning in 2003
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.