Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 93, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 11, 1987, 10:22 PM CDT for Lyon County, Sioux County, Iowa. It was in force for 68 min.
The area
The counties it named.
The facts
- Issued
- Jul 11, 1987, 10:22 PM CDT (03:22 UTC)
- Expired
- Jul 11, 1987, 11:30 PM CDT
- In force
- 68 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
Counties Lyon County, IA, Sioux County, IA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 3.4 hours before the alert went out and 213 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
- 3602 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 98 m²/s²
- 0-3 km storm-relative helicity
- 145 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 120322
SVRFSD
IAC119-167-MNC033-101-105-120430-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1022 PM CDT SAT JUL 11 1987
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 1130 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES...
IN NORTHWEST IOWA
...LYON...SIOUX
IN SOUTHWEST MINNESOTA
...COTTONWOOD...EASTERN MURRAY...NOBLES
SOME CITIES EFFECTED ARE...JEFFERS..WORTHINGTON IN SOUTHWEST
MINNESOTA AND GEORGE AND SIOUX CENTER IN NORTHWEST IOWA.
AT 1015 PM CDT GOLF BALL SIZE HAIL WAS REPORTED A FEW MILES WEST OF
SLAYTON MINNESOTA IN MURRAY COUNTY.
{ Basis }
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.
KOSCIELSKIWhat 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, Jul 11, 7:18 PM CDT, 3 hours 4 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 715 PM CDT SAT JUL 11 1987 ...INTENSE THUNDERSORMS CONTINUE TO DEVELOPE ACROSS SOUTHEAST SOUTH DAKOTA... AT 7 PM CDT A LINE OF INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN FALL CONTINUED TO DEVELOPE ACROSS SOUTHEAST SOUTH DAKOTA. THE LINE EXTENDED FROM 80 MILES SOUTHWEST OF SIOUX FALLS...NEAR PICKSTOWN TO 70 MILES NORTHWEST OF SIOUX FALLS...NEAR CARTHAGE. THESE THUNDERSTORMS ARE CAPABLE OF PRODUCING VERY HEAVY RAIN... SMALL HAIL...GUSTY SURFACE WINDS AND DANGEROUS LIGHTNING AS THEY MOVE NORTHEAST AT 25 MILES AN HOUR. PERSONS IN THE SOUTH DAKOTA COUNTIES OF MINER...DAVISON...HANSON ...DOUGLAS AND CHARLES MIX INC+LUDING THE COMMUNITIES OF PICKSTOWN ...ARMOUR...MITCHELL AND VILAS SHOULD BE ON THE LOOKOUT FOR THESE STORMS THROUGH 9 PM CDT. PERSONS SHOULD STAY TUNED TO THEIR LOCAL TV AND RADIO STATIONS FOR FURTHER STATEMENTS AND POSSIBLE WARNINGS. BUSS
Special weather statement, Jul 11, 8:04 PM CDT, 2 hours 18 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 805 PM CDT SAT JUL 11 1987 ...THUNDERSTORMS WITH HEAVY RAIN CONTINUE ACROSS SOUTHEAST SOUTH DAKOTA... AT 8 PM CDT A LINE OF SCATTERED THUNDERSTORMS WITH HEAVY RAIN CONTINUED ACROSS SOUTHEAST SOUTH DAKOTA. THE LINE EXTENDED FROM 70 MILES SOUTHWEST OF SIOUX FALLS...NEAR PICKSTOWN TO 60 MILES NORTH OF SIOUX FALLS...NEAR BROOKINGS. THESE STORMS WERE PRODUCING HEAVY RAINw AND ARE CAPABLE OF PRODUCING SMALL HAIL...GUSTY SURFACE WINDS AND DANGEROUS LIGHTNING AS THEY MOVE EAST AT 25 MILES AN HOUR. BUSS
Special weather statement, Jul 11, 8:40 PM CDT, 1 hour 42 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 835 PM CDT SAT JUL 11 1987 ...TORNADO WATCH FOR PORTIONS OF CENTRAL AND EASTERN SOUTH DAKOTA UNTIL MIDNIGHT CDT THIS SATURDAY NIGHT... AT 830 PM CDT...NUMEROUS INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED OVER MOST OF CENTRAL AND EASTERN SOUTH DAKOTA. THE AREA OF PRECIPITATION WAS BOUNDED BY THE MISSOURI RIVER AND THE EASTERN SOUTH DAKOTA BORDER. THE STRONGEST THUNDERSTORMS WERE 20 MILES WEST OF HURON...NEAR WOLSEY...30 MILES NORTHWEST OF SIOUX FALLS...NEAR SALEM AND 25 MILES EAST OF MOBRIDGE...NEAR JAVA. ALL MOVEMENT WAS EAST AT 30 MILES AN HOUR. THESE STORMS ARE CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING AND HAIL. IF YOU ARE IN THE PATH OF THESE STORMS YOU SHOULD TAKE COVER. THE HURON AREA CAN EXPECT STRONG GUSTY WINDS...FREQUENT LIGHTNING ...HEAVY RAIN AND HAIL BEFORE 900 PM CDT. EDDY
Special weather statement, Jul 11, 9:20 PM CDT, 1 hour 2 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 915 PM CDT SAT JUL 11 1987 ...INTENSE THUNDERSORMS WERE INCREASING ACROSS SOUTHEAST SOUTH DAKOTA... AT 9 PM CDT A LINE OF INTENSE THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED TO INCREASE ACROSS SOUTHEAST SOUTH DAKOTA. THE LINE EXTENDED FROM 70 MILES SOUTHWEST OF SIOUX FALLS...NEAR SPRING/ FIELD TO 60 MILES NORTH OF SIOUX FALLS...NEAR BROOKINGS. THESE STORMS WERE PRODUCING VERY HEAVY RAIN AND ARE CAPABLE OF PRODUCING HAIL... STRONG GUSTY WINDS AND DANGEROUS LIGHTNING AS THEY MOVE TO THE EAST AT 25 MILES AN HOUR. PERSONS IN THE SOUTH DAKOTA COUNTIES OF MOODY...MINNEHAHA...MCCOOK... TURNER AND LINCOLN INCLUDING THE COMMUNITIES OF FLANDREAU...SIOUX FALLS ...DELL RAPIDS AND MARION SHOULD BE ON THE LOOKOUT FOR THESE STORMS THROUGH 10 PM CDT. STAY TUNED TO YOUR LOCAL TV OR RADIO STATION FOR FURTHER STATEMENTS OR POSSIBLE WARNINGS. BUSS
Special weather statement, Jul 11, 9:38 PM CDT, 44 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 935 PM CDT SAT JUL 11 1987 ...TORNADO WATCH FOR PORTIONS OF CENTRAL AND EASTERN SOUTH DAKOTA UNTIL MIDNIGHT CDT THIS SATURDAY NIGHT... AT 930 PM CDT...A LINE OF INTENSE THUNDERSTORMS CONTINUED TO MOVE OVER SOUTHEAST SOUTH DAKOTA AND WESTERN MINNESOTA. THE LINE OF THUNDERSTORMS WAS ALONG AND 10 MILES EITHER SIDE OF A LINE FROM YANKTON TO SIOUX FALLS TO BROOKINGS. THE STRONGEST THUNDERSTORMS WERE JUST WEST OF YANKTON AND 10 MILES NORTH OF YANKTON. THE LINE OF THUNDERSTORMS WAS MOVING EAST AT 30 MILES AN HOUR. THESE STORMS ARE CAPABLE OF PRODUCING STRONG GUSTY WINDS...FREQUENT LIGHTNING AND HAIL. IF YOU ARE IN THE PATH OF THESE STORMS YOU SHOULD SEEK SHELTER. OTHERWISE...SCATTERED SHOWERS AND THUNDERSTORMS CONTINUED OVER MOST OF CENTRAL AND EASTERN SOUTH DAKOTA. THESE SHOWERS AND THUNDERSTORMS WERE EAST OF A LINE FROM MOBRIDGE TO PIERRE (TO MITCHELL AND WERE MOVING EAST AT 30 MILES AN HOUR. EDDY
Special weather statement, Jul 11, 10:20 PM CDT, 2 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 1020 PM CDT SAT JUL 12 1987 ...THUNDERSTORMS WITH HEAVY RAIN CONTINUED ACROSS SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA... AT 1015 PM CDT A LINE OF SCATTERED THUNDERSORMS WITH HEAVY RAIN CONTINUED ACROSS SOUTHEAST SOUTH DAKOTA AND INTO SOUTHWEST MINNESOTA. THE LINE EXTENDED FROM 35 MILES SOUTH OF SIOUX FALLS...NEAR CENTERVILLE SOUTH DAKOTA TO 70 MILE NORTHEAST OF SI"OUX FALLS...NEAR MARSHALL MINNESOTA. THESE STORMS ARE CAPABLE OF PRODUCING HEAVY RAIN...SMALL HAIL... GUSTY SURFACE WINDS AND DANGEROUD LIGHTNING AS THEY MOVE TO THE EAST AT 25 MILES AN HOUR. BUSS
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 11, 10:54 PM CDT | Severe Thunderstorm Warning | FSD | Osceola | 66 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; the sounding from the Mesonet's radiosonde archive.