Severe Thunderstorm Warning 177, NWS Des Moines, IA

Issued

Aug 12, 2002, 9:29 PM CDT (02:29 UTC)

Expired

Aug 12, 2002, 9:50 PM CDT

In force

21 min

Issued by

NWS Des Moines, IA

Area

Counties, with a storm outline in the text

County Adams County, IA

The Des Moines radar (KDMX), 107 km from the middle of the area, began a volume at 02:30 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.

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.

616 
WUUS53 KDMX 130229
SVRDSM
IAC003-130250-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
928 PM CDT MON AUG 12 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN ADAMS COUNTY IN SOUTHWEST IOWA

* UNTIL 950 PM CDT

* AT 925 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A LINE
  OF SEVERE THUNDERSTORMS FROM 5 MILES NORTH OF PRESCOTT TO 9 MILES
  SOUTHEAST OF PRESCOTT...OR FROM 60 MILES SOUTHWEST OF DES MOINES TO
  66 MILES SOUTHWEST OF DES MOINES...MOVING EAST AT 30 MPH.

* SEVERE THUNDERSTORMS WILL BE...
  IN RURAL AREAS OF
  EASTERN ADAMS COUNTY AND   IN RURAL AREAS OF
  NORTHEASTERN ADAMS COUNTY.

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.

LAT...LON 4115 9478 4091 9467 4091 9449 4115 9449

JOHNSON

NWS Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 12, 2:00 PM CDT, 7 hours 29 minutes earlier.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DES MOINES IA
200 PM CDT MON AUG 12 2002

AFD COMPOSED EARLY.  THERE MAY BE LAST MINUTE CHANGES TO FORECAST
THINKING.

CDFNT FM SRN MN SW INTO EARN NE AT 18Z.  SE SFC WINDS OVER WRN IA
INCREASED EARLY THIS AFTERNOON AND VSBY SATELLITE PICS SHOWING
MID/HI CLOUDS THINNING ATTM.  TEMPS RECOVERED INTO THE LOWER 80S
EARLY THIS AFTERNOON.  THINKING ATTM IS THAT AMS SHUD DESTABILIZE
ENOUGH TO SUPPORT TSTMS WHICH SHOULD INCREASE IN COVERAGE OVER WRN
IA AND THEN SPREAD ACRS FA THIS EVENING.  SE SFC FLOW AHEAD OF FRONT
INTO FRONTAL BOUNDARY AIDING IN AREA OF STRONG MOISTURE FLUX CNVG
NEAR BOUNDARY.  THIS SHOULD BE THE MOST LIKELY AREA OF DEVELOPMENT
THIS AFTERNOON. WILL GO WITH HI POPS TONIGHT.

CDFNT SE OF IA BY 12Z TUESDAY. AVN PRINTS SOME PCPN OVER SRN FA
TUESDAY DUE TO S/WV ROTATING THROUGH THE TROF CREATING SOME PCPN
NORTH OF THE BOUNDARY.  ETA LESS AGGRESSIVE WITH THIS FEATURE.  WILL
KEEP CURRENT FCST OF MORNING POPS SRN FA FOR NOW DUE TO THIS.

DRY WX REST OF SHORT TERM FORECAST AND LESS HUMID.  NEW GUIDANCE IN
LINE WITH CURRENT TEMP GRIDS AND ONLY MADE MINOR ADJUSTMENTS.

12Z AVN DIFFERENT THAN 00Z MRF WITH RESPECT TO FROPA FRIDAY NIGHT.
12Z AVN DRIVES FRONT THROUGH FA FRIDAY NIGHT WHILE OLD MRF KEEPS
BOUNDARY N.  IN EITHER CASE...EXPECT BOUNDARY NEAR IA THIS WEEKEND
GIVEN WSW FLOW ALOFT AND IA NEAR SRN EDGE OF WESTERLIES.  WILL TIME
PCPN BASED ON 12Z AVN AND KEEP CHANCES IN DAY 6 AND 7 BASED ON
ABOVE.  NEAR OR SLIGHTLY BLO NORMAL TEMPS.

.DSM...NONE

JOHNSON

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

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.