Alert archive / South Dakota / Severe Thunderstorm Warnings in 1990

Severe Thunderstorm Warning 108, NWS Sioux Falls, SD

July 18, 1990Union County, South Dakota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 18, 1990, 10:20 AM CDT for Union County, South Dakota. It was in force for 40 min.

The area

The counties it named.

The facts

Issued
Jul 18, 1990, 10:20 AM CDT (15:20 UTC)
Expired
Jul 18, 1990, 11:00 AM CDT
In force
40 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Union County, SD

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 12:00Z, 3.3 hours before the alert went out and 170 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 12:00Z on 1990-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 1990-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3632 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
138 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSUX 181520
SVRSUX
SDC127-181600-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING 
NATIONAL WEATHER SERVICE SIOUX CITY IA
1020 AM CDT WED JUL 18 1990

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 1100 AM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY

   IN THE SOUTHEAST PART OF SOUTH DAKOTA
      NORTHWEST UNION

AT 1019 AM CDT RADAR SHOWED A SEVERE THUNDERSTORM 5 MILES SOUTH OF
BERESFORD SOUTH DAKOTA. THE STORM WAS MOVING EAST AT 25 MPH.

ALCESTER AND NORA ARE IN THE PATH OF THIS STORM.

REMEMBER...SEVERE THUNDERSTORMS CAN PRODUCE DAMAGING WINDS IN EXCESS
OF 60 MPH...LARGE HAIL...DEADLY LIGHTNING...AND HEAVY RAINS THAT CAN
QUICKLY FLOOD LOW LYI2NG AREAS. IF YOU ARE IN THE PATH OF THIS STORM
TAKE SHELTER IN A REINFORCED BUILDING IMMEDIATELY.

ASK THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR REPORTS
OF SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE.

HOPPES

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

Special weather statement, Jul 18, 5:06 AM CDT, 5 hours 14 minutes before
SDZ018-020-181110-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
506 AM CDT WED JUL 18 1990

STRONG THUNDERSTORMS WITH VERY HEAVY RAIN WERE LOCATED FROM 10 MILES
SOUTH OF SIOUX FALLS TO 30 MILES SOUTH OF SIOUX FALLS NEAR BERESFORD.
ANOTHER STRONG THUNDERSTORM WAS LOCATED 15 MILES SOUTHWEST OF SIOUX
FALLS.

THESE THUNDERSTORMS CONTAIN VERY HEAVY RAIN AND FREQUENT LIGHTNING
AND ARE CAPABLE OF PRODUCING GUSTY SURFACE WINDS AND HAIL.

MOVEMENT WAS EAST AT 20 MILES AN HOUR.
SHEEHAN
Special weather statement, Jul 18, 6:10 AM CDT, 4 hours 10 minutes before
SDZ018-IAZ001-181210-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
610 AM CDT WED JUL 18 1990

AT 6AM CDT THUNDERSTORMS WITH VERY HEAVY RAIN HAD MOVED INTO NORTHWEST
IOWA.

THUNDERSTORMS EXTENDED FROM 10 MILES SOUTHEAST OF SIOUX FALLS TO 45
MILES SOUTHEAST OF SIOUX FALLS NEAR SIOUX CENTER IOWA.

THESE THUNDERSTORMS CONTAIN VERY HEAVY RAIN AND FREQUENT LIGHTNING
AND ARE CAPABLE OF PRODUCING GUSTY SURFACE WINDS AND HAIL.

PEOPLE IN NORTHWEST IOWA SHOULD KEEP ON THE ALERT AND BE PREPARED
TO SEEK SHELTER IF THREATNING WEATHER APPROACHES.

MOVEMENT WAS EAST AT 20 MILES AN HOUR.
SHEEHAN
Special weather statement, Jul 18, 7:05 AM CDT, 3 hours 15 minutes before
SDZ018-IAZ001-181310-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
706 AM CDT WED JUL 18 1990

AT 7AM CDT THUNDERSTORMS WITH VERY HEAVY RAIN WERE LOCATED ACROSS
NORTHWEST IOWA AND EXTREME SOUTHEAST SOUTH DAKOTA.

A LINE OF THUNDERSTORMS EXTENDED FROM 20 MILES NORTHWEST OF SPENCER
TO 20 MILES SOUTHWEST OF SPENCER IOWA. ANOTHER THUNDERSTORM WAS
LOCATED 10 MILES SOUTH OF SIOUX FALLS.

THESE THUNDERSTORMS CONTAIN VERY HEAVY RAIN AND FREQUENT LIGHTNING
AND ARE CAPABLE OF PRODUCING GUSTY SURFACE WINDS AND HAIL.

PEOPLE IN NORTHWEST IOWA SHOULD KEEP ON THE ALERT AND BE PREPARED
TO SEEK SHELTER IF THREATNING WEATHER APPROACHES.

MOVEMENT WAS EAST AT 20 MILES AN HOUR.
SHEEHEAN
Special weather statement, Jul 18, 8:03 AM CDT, 2 hours 17 minutes before
SDZ018-IAZ001-181410-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
804 AM CDT WED JUL 18 1990

AT 8 AM CDT THUNDERSTORMS WITH VERY HEAVY RAIN WERE LOCATED 10 MILES
SOUTHEAST AND 15 MILES EAST OF SIOUX FALLS SOUTH DAKOTA.

THESE THUNDERSTORMS ARE PRODUCING VERY HEAVY RAIN AND MAY BE
ACCOMPANIED BY GUSTY SURFACE WINDS AND HAIL.

OTHER SHOWERS AND THUNDERSTORMS EXTENDED FROM 20 MILES SOUTHEAST OF
SIOUX FALLS TO 20 MILES SOUTH OF SPENCER IOWA.

MOVEMENT WAS EAST AT 20 MILES AN HOUR.
SHEEHAN
Special weather statement, Jul 18, 9:02 AM CDT, 1 hour 18 minutes before
SDZ018-IAZ001-181510-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
902 AM CDT WED JUL 18 1990

AT 9 AM CDT THUNDERSTORMS WITH VERY HEAVY RAIN WERE LOCATED 15 MILES
SOUTHEAST AND 40 MILES SOUTHEAST OF SIOUX FALLS SOUTH DAKOTA.

THESE THUNDERSTORMS ARE PRODUCING VERY HEAVY RAIN...GUSTY SURFACE
WINDS AND SMALL HAIL.

OTHER SHOWERS AND THUNDERSTORMS EXTENDED FROM 15 MILES SOUTHWEST OF
SIOUX FALLS NEAR LENNOX TO 20 MILES SOUTH OFH SPENCER IOWA NEAR SIOUX
RAPIDS IOWA.

MOVEMENT WAS EAST AT 25 MILES AN HOUR.
 BERG
Special weather statement, Jul 18, 10:02 AM CDT, 18 minutes before
SDZ018-020-IAZ001-181610-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
10 AM CDT WED JUL 18 1990

AT 10 AM CDT SCATTERED THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUED
ACROSS SOUTHEAST SOUTH DAKOTA AND NORTHWEST IOWA.

THESE THUNDERSTORMS ARE PRODUCING VERY HEAVY RAIN...GUSTY SURFACE
WINDS AND SMALL HAIL.

THE PRECIPITATION WAS LOWCATED ALONG A LINE FROM 20 MILES WEST OF
YANKTON NEAR TYNDALL TO 10 MILES WEST OF SPENCER IOWA NEAR HARTLEY.

MOVEMENT WAS EAST AT 25 MILES AN HOUR.
 BERG

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 4:36 AM CDTSevere Thunderstorm WarningFSDLincoln39 min
Jul 18, 4:36 AM CDTSevere Thunderstorm WarningFSDTurner21 min
Jul 18, 5:16 AM CDTSevere Thunderstorm WarningFSDMinnehaha29 min
Jul 18, 5:45 AM CDTSevere Thunderstorm WarningFSDMinnehaha30 min
Jul 18, 10:17 AM CDTSevere Thunderstorm WarningFSDClay, Lincoln43 min
Jul 18, 10:54 AM CDTSevere Thunderstorm WarningFSDLincoln66 min
Jul 18, 11:28 AM CDTSevere Thunderstorm WarningFSDMcCook, Turner47 min
Jul 18, 11:42 AM CDTSevere Thunderstorm WarningFSDLincoln33 min
Jul 18, 12:12 PM CDTSevere Thunderstorm WarningFSDLincoln33 min
Jul 18, 4:34 PM CDTSevere Thunderstorm WarningFSDBrookings41 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 1990Every severe thunderstorm warning in 1990

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.