Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 9, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 7, 1987, 5:09 PM CDT for Lyon County, Iowa. It was in force for 66 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
- Jun 7, 1987, 5:09 PM CDT (22:09 UTC)
- Expired
- Jun 7, 1987, 6:15 PM CDT
- In force
- 66 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Lyon 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 |
|---|---|---|---|
| Jun 7, 6:18 PM CDT | Tornado F0 | Lyon, 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, 10.2 hours before the alert went out and 230 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
- 3626 m above ground
- 0-6 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- 48 m²/s²
- 0-3 km storm-relative helicity
- 74 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 KFSD 072209
SVRFSD
IAC119-072315-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
509 PM CDT SUN JUN 7 1987
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 615 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY...
IN NORTHWEST IOWA
...LYON
AT 510 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 20 MILES
SOUTHEAST OF SIOUX FALLS NEAR LESTER...MOVING SOUTHEAST AT 15 MPH.
SOME OTHER CITIES INCLUDIED IN THIS WARNING ARE ROCK RAPIDS AND
GEORGE.
IF YOU ARE IN THE PATH OF THIS STORM...YOU SHOULD GET TO A
REINFORCED SHELTER. A SEVERE THUNDERSTORM PRODUCES WINDS IN EXCESS
OF 60 MPH...HAIL 3/4 INCH OR LARGER...DEADLY LIGHTNING...AND HEAVY
RAIN THAT CAN QUICKLY FLOOD A LOW LYING AREA.
KAPELAWhat 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
Special weather statement, Jun 7, 4:28 PM CDT, 41 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 426 PM CDT SUN JUN 7 1987 ...A SEVERE THUNDERTSTORM WATCH FOR SOUTHEAST AND EAST SOUTH DAKOTA AND PARTS OF SOUTHWEST MINNESOTA UNTIL 10 PM CDT... AT 420 PM CDT THUNDERSTORMS CONTINUED TO DEVELOPE ACROSS SOUTHEAST SOUTH DAKOTA AND A SMALL PORTION OF SOUTHWEST MINNESOTA. THE THUNDERSTORMS IN SOUTH DAKOTA WERE LOCATED 60 MILES WEST OF SIOUX FALLS...NEAR PARKSTON SOUTH DAKOTA AND IN MINNESOTA A THUND/ ERSTORM WAS LOCATED SOUTHEAST OF PIPESTONE...35 MILES NORTHEAST OF SIOUX FALLS. THESE THUNDERSTORMS WERE MOVING EAST AT 20 MILES AN HOUR AND MAY BECOME CAPABLE OF PRODUCING HEAVY RAIN...GUSTY WINDS...HAIL AND DANGERIOUS LIGHTNING. STAY TUNED TO THIS STATION FOR ADDITIONAL STATEMENTS AND WARNINGS AND POSSIBLE WARNINGS. BUSS
Special weather statement, Jun 7, 4:33 PM CDT, 36 minutes before
SPECIAL WEATHER STATEMENT CORRECTION NATIONAL WEATHER SERVICE SIOUX FALLS SD 426 PM CDT SUN JUN 7 1987 ...A SEVERE THUNDERTSTORM WATCH FOR SOUTHEAST AND EAST SOUTH DAKOTA AND PARTS OF SOUTHWEST MINNESOTA UNTIL 10 PM CDT... AT 420 PM CDT THUNDERSTORMS CONTINUED TO DEVELOPE ACROSS SOUTHEAST SOUTH DAKOTA AND A SMALL PORTION OF SOUTHWEST MINNESOTA. THE THUNDERSTORMS IN SOUTH DAKOTA WERE LOCATED 60 MILES WEST OF SIOUX FALLS...NEAR PARKSTON SOUTH DAKOTA AND IN MINNESOTA A THUND/ ERSTORM WAS LOCATED SOUTHEAST OF PIPESTONE...35 MILES NORTHEAST OF SIOUX FALLS. THESE THUNDERSTORMS WERE MOVING EAST AT 20 MILES AN HOUR AND MAY BECOME CAPABLE OF PRODUCING HEAVY RAIN...GUSTY WINDS...HAIL AND DANGEZROUS LIGHTNING. STAY TUNED TO THIS STATION FOR ADDITIONAL STATEMENTS AND POSSIBLE WARNINGS. BUSS
Special weather statement, Jun 7, 4:45 PM CDT, 24 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 440 PM CDT SUN JUN 7 1987 ...SEVERE THUNDERSTORM WATCH FOR SOUTHERN AND EASTERN SOUTH DAKOTA AND INTO MINNESOTA UNTIL 10 PM CDT... AT 425 PM CDT...WIDELY SCATTERED THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED TO DEVELOPED OVER CENTRAL AND EASTERN SOUTH DAKOTA AND WESTERN MINNESOTA. SCATTERED THUNDERSTORMS CONTINUED OVER NORTHERN SOUTH DAKOTA AND SOUTHEASTEhRN NORTH DAKOTA. IN SOUTH DAKOTA...THE STRONGEST STORMS WERE 25 MILES SOUTH OF MITCHELL...NEAR ARMOUR AND PARKSTON. MOVEMENT WAS EAST AT 20 MILES AN HOUR. EDDY
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 7, 6:18 PM CDT | Severe Thunderstorm Warning | FSD | Lyon | 57 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1987Every severe thunderstorm warning in 1987
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.