Alert archive / Iowa / Severe Thunderstorm Warnings in 1996

Severe Thunderstorm Warning 8, NWS Sioux Falls, SD

May 17, 1996O'Brien County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at May 17, 1996, 8:45 PM CDT for O'Brien County, Iowa. It was in force for 30 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 17, 1996, 8:45 PM CDT (01:45 UTC)
Expired
May 17, 1996, 9:15 PM CDT
In force
30 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County O'Brien County, IA

The radar

The Sioux Falls radar (KFSD), 105 km from the middle of the area, began a volume at 01:47 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

TimeReportWhereRemark
May 17, 8:51 PM CDTHail 1Sanborn, IA
May 17, 8:55 PM CDTHail 1.75Sanborn, IA
May 17, 9:00 PM CDTHail 0.75Sanborn, 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 nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.8 hours before the alert went out and 206 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-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 1996-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3864 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 1996-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -24 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
3864 J/kg
Mixed-layer CIN
-15 J/kg
Mixed-layer LCL
1845 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
-24 m²/s²
0-3 km storm-relative helicity
32 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KFSD 180145
SVRFSD
IAC141-180215-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
845 PM CDT FRI MAY 17 1996

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 915 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN NORTHWEST IOWA

   ...WESTERN O'BRIEN COUNTY
 
AT 842 PM CDT...A SEVERE THUNDERSTORM WAS DETECTED BY SIOUX FALLS
DOPPLER RADAR 25 MILES SOUTH OF SIBLEY  OR NEAR PHILBY MOVING
NORTHEAST AT 40 MPH.

THIS STORM CAN BE EXPECTED IN THE VICINITY OF...
ARCHER                   AROUND 855 PM CDT
SANBORN                  AROUND 905 PM CDT
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...
DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.  FOR YOUR
PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS.

SEVERE THUNDERSTORMS CAN AND OFTEN DO PRODUCE TORNDAOES WITH LITTLE
OR NO WAR.NING.  REMEMBER...A TORNADO WATCH IS IN EFFECT FOR
NORTHWEST  IOWA UNTIL 11 PM CDT.

CHAPMAN

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.

In the hours before

Local storm report, May 17, 7:05 PM CDT, 1 hour 40 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE  SIOUX FALLS SD
705 PM CDT FRI MAY 17 1996

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

0410 PM    WESSINGTON                SD   0.75 INCH HAIL
05/17/96   BEADLE

CHAPMAN
Special weather statement, May 17, 7:13 PM CDT, 1 hour 32 minutes before
SDZ007-011-019-020-022-023-039-040-054>056-060>062-180200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
710 PM CDT FRI MAY 17 1996

...TORNADO WATCH NUMBER 383 CANCELLED FOR FAR EASTERN SOUTH DAKOTA
EXCEPT CONTINUED UNTIL 9 PM CDT EXTREME NORTHEAST...

THE NATIONAL WEATHER SERVICE HAS CANCELLED THE PART OF TORNADO WATCH
NUMBER 383 THAT WAS IN EFFECT FOR MOST OF FAR EASTERN SOUTH DAKOTA...
EXCEPT FOR THE EXTREME NORTHEAST WHEREf THE WATCH CONTINUES UNTIL 9 PM
CDT FOR ROBERTS AND GRANT COUNTIES.

WILLIAMS
Special weather statement, May 17, 8:11 PM CDT, 34 minutes before
SDZ008-021-180200-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
810 PM CDT FRI MAY 17 1996

...TORNADO WATCH NUMBER 383 CANCELLED FOR EXTREME NORTHEAST SOUTH
DAKOTA...

THE NATIONAL WEATHER SERVICE HAS CANCELLED THE PART OF TORNADO WATCH
NUMBER 383 THAT WAS IN EFFECT FOR EXTREME NORTHEAST SOUTH DAKOTA.

WILLIAMS

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 17, 8:33 PM CDTSevere Thunderstorm WarningFSDSioux32 min
May 17, 8:57 PM CDTSevere Thunderstorm WarningFSDOsceola33 min
May 17, 9:14 PM CDTSevere Thunderstorm WarningFSDDickinson31 min
May 17, 9:20 PM CDTSevere Thunderstorm WarningFSDWoodbury35 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1996Every severe thunderstorm warning in 1996

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.