Alert archive / Iowa / Tornado Warnings in 1986
Tornado Warning 18, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this tornado warning at Jul 28, 1986, 6:51 PM CDT for Woodbury County, Iowa. It was in force for 39 min. 1 report 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
- Jul 28, 1986, 6:51 PM CDT (23:51 UTC)
- Expired
- Jul 28, 1986, 7:30 PM CDT
- In force
- 39 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Woodbury County, IA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 28, 7:02 PM CDT | Hail 0.75 | Woodbury, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 11.9 hours before the alert went out and 122 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3629 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 110 m²/s²
- 0-3 km storm-relative helicity
- 135 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KSUX 282352 TORSUX IAC193-290030- BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE SIOUX CITY IA 651 PM CDT MON JUL 28 1986 THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING EFFECTIVE UNTIL 730 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF WEST CENTRAL IOWA...WOODBURY THIS WARNING INCLUDES THE CITIES OF SIOUX CITY. AT 650 PM CDT A TORNADO WAS ON THE GROUND 1 MILE NORTHWEST OF NORTH SIOUX CITY SOUTH DAKOTA. THE STORM WAS MOVING SOUTHEAST AT 25 MILES AN HOUR. IF YOU ARE IN THE PATH OF THIS TORNADO..GO TO A BASEMENT SHELTER OR A CENTRAL INTERIOR ROOM ON THE LOWEST FLOOR. ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING IF AVAILABkLE..IF NOT..LIE IN A NEARBY DITCH OR DEPRESSION. THIS IS A DANGEROUS STORM. TAKE COVER IMMEDIATELY. PLEASE ASK THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR REPORT OF SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE. ROSNER
What forecasters said that day
The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
In the hours before
Special weather statement, Jul 28, 2:43 PM CDT, 4 hours 8 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 240 PM CDT MON JUL 28 1986 AT 230 PM CDT...SCATTERED THUNDERSTORMS WITH HEAVY RAIN..AND AN ISOLATED INTENSE STORM WITH VERY HEAVY RAIN.. CONTINUED JUST SOUTH OF THE SOUTH DAKOTA..NORTH DAKOTA BORDER. THE STRONGEST THUNDERSTORM WAS 40 MILES EAST OF MOBRIDGE.. NEAR HOSMER. THIS THUNDERSTORM WAS PART OF A LARGER AREA OF SHOWERS AND THUNDERSTORMS..WHICH EXTENDED FROM NEAR MOBRIDGE.. TO NEAR THE BORDER INTERSECTION OF SOUTH DAKOTA.. NORTH DAKOTA..AND MINNESOTA. SMALL HAIL..GUSTY WINDS..AND VERY HEAVY RAINS ARE POSSIBLE WITH THESE STORMS. ALSO..SCATTERED SHOWERS AND THUNDERSTORMS WERE BEGINNING TO DEVELOP OVER PARTS OF CENTRAL AND NORTHEASTERN SOUTH DAKOTA. IN CENTRAL SOUTH DAKOTA..THESE WERE FROM 30 MILES NORTH OF PIERRE..TO 30 MILES SOUTHWEST OF PIERRE. THESE STORMS COULD ALSO PRODUCE SMALL HAIL..GUSTY WINDS..AND HEAVY RAINS. PERSONS IN RECREATION AREAS ALONG THE MISSOURI RIVER SHOULD BE AWARE OF CHANGING WEATHER CONDITIONS AND BE PREPARED TO TAKE PROTECTIVE ACTIONS. IN NORTHEASTERN SOUTH DAKOTA..AN ISOLATED THUNDERSHOWER WAS JUST NORTHWEST OF WATERTOWN. ALL MOVEMENT WAS EAST AT 30 MILES AN HOUR.
Special weather statement, Jul 28, 5:23 PM CDT, 1 hour 28 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 523 PM CDT MON JUL 28 1986 ...SEVERE THUNDERSTORM WARNING LINCOLN COUNTY MINNESOTA AND EXTREME NORTHEAST BROOKINGS COUNTY SOUTH DAKOTA TIL 545 PM CDT... ...SEVERE THUNDERSTORM WARNING BRULE AND AURORA COUNTIES SOUTH DAKOTA TIL 545 PM CDT... AT 458 PM CDT A POSSIBLE FUNNEL CLOUD WAS REPORTED NEAR KIMBALL SOUTH DAKOTA WHICH DISSIPATED BY 505 PM CDT. AT 501 PM CDT MARBALL SIZE HAIL WAS REPORTED NEAR IVANHOE MINNESOTA. AT 511 PM CDT GOLF BALL SIZE HAIL AND 55 TO 60 MPH WINDS WERE REPORTED AT KIMBALL SOUTH DAKOTA. AT 517 PM RADAR SHOWED THE CENTERS OF THE SEVERE THUNDERSTORMS ABOUT 35 MILES WEST OF MITCHELL AND 25 MILES EAST OF BROOKINGS. THESE THUNDERSTORMS WERE MOVING SOUTHEAST ABOUT 25 MPH. SEVERE THUNDERSTORMS CAN PRODUCE LARGE HAIL...DAMAGING WINDS... CONSIDERABLE CLOUD TO GROUND LIGHTNING AND VERY HEAVY RAIN. PERSONS NEAR AND TO THE SOUTHEAST OF nTHESE THUNDERSTORMS SHOULD BE PREPARED FOR THIS ADVERSE WEATHER AND MOVE TO A SAFE PLACE IF NECESSARY. BLOOM
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 28, 6:24 PM CDT | Severe Thunderstorm Warning | FSD | O'Brien | 66 min |
| Jul 28, 6:28 PM CDT | Severe Thunderstorm Warning | FSD | Sioux | 62 min |
Nearby
Tornado Warnings in Iowa, 1986Every tornado warning in 1986Tornadoes in 1986
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.