Alert archive / Iowa / Severe Thunderstorm Warnings in 1989
Severe Thunderstorm Warning 65, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 5, 1989, 4:20 AM CDT for Sioux County, Iowa. It was in force for 25 min.
The area
The counties it named.
The facts
- Issued
- Aug 5, 1989, 4:20 AM CDT (09:20 UTC)
- Expired
- Aug 5, 1989, 4:45 AM CDT
- In force
- 25 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County 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, 9.3 hours before the alert went out and 197 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
- 31 J/kg
- Mixed-layer CIN
- -246 J/kg
- Mixed-layer LCL
- 3581 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 31 m²/s²
- 0-3 km storm-relative helicity
- 90 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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, Aug 5, 4:04 AM CDT, 16 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX CITY IA 400 AM CDT AUG 05 1989 ...STRONG THUNDERSTORM OVER NORTHERN UNION COUNTY SOUTH DAKOTA AND SIOUX COUNTY IOWA... AT 355 AM CDT RADAR SHOWED THAT A VERY STRONG THUNDERSTORMS HAD FORMED FROM 30 TO 40 MILES NORTH TO NORTHWEST OF SIOUX CITY...OVER NORTHERN UNION COUNTY SOUTH DAKOTA AND SOUTHWEST SIOUX COUNTY IOWA. MOVEMENT WAS EAST AT 25 MILES AN HOUR. THIS DIRECTION AND SPEED WILL TAKE THESE STORMS OVER THE TOWNS OF ALCESTER AND BIG SPRINGS IN UNION COUNTY AND HAWARDEN...CHATSWORTH...MAURICE...ORANGE CITY AND ALTON IN SIOUX COUNTY IOWA...BETWEEN 400 AND 500 AM. THESE STORMS HAVE THE POTENTIAL FOR SMALL HAIL...HEAVY RAIN SHOW*ERS... DANGEROUS LIGHTNING AND STRONG GUSTY WINDS. RESIDENTS OF THE UNION AND PLYMOUTH COUNTY AREA SHOULD WATCH THE WEATHER CLOSELY AND BE PREPARED TO GO TO A SAFE SHELTER IF SEVERE WEATHER SHOULD DEVELOPE. SHERLIN
Special weather statement, Aug 5, 4:09 AM CDT, 11 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 410 AM CDT SAT AUG 5 1989 AT 405 AM CDT A THUNDERSTORM WITH VERY HEAVY RAIN AND HAIL LOCATED 38 MILES SOUTH SOUTHEAST OF SIOUX FALLS IN SOUTHWEST SIOUX COUNTY WAS MOVING TO THE EAST AT 35 MPH. THIS STORM IS EXPECTED TO REACH SIOUX CENTER IOWA AROUND 415 AM CDT AND ALTON IOWA AROUND 430 AS IT TRACKS EASTWARD ACROSS SIOUX COUNTY. RESIDENTS OF SIOUX COUNTY...ESPECIALLY THE S2OUTHERN TWO THIRDS OF SIOUX COUNTY SHOULD BE ALERT TO THE POSSIBILITY OF STRONG GUSTY WINDS AND HAIL AS THIS THUNDERSTORM MOVES THROUGH. BIER
Special weather statement, Aug 5, 4:15 AM CDT, 5 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX CITY IA 400 AM CDT AUG 05 1989 ...STRONG THUNDERSTORM OVER NORTHERN UNION COUNTY SOUTH DAKOTA AND SIOUX COUNTY IOWA... AT 355 AM CDT RADAR SHOWED THAT A VERY STRONG THUNDERSTORMS HAD FORMED FROM 30 TO 40 MILES NORTH TO NORTHWEST OF SIOUX CITY...OVER NORTHERN UNION COUNTY SOUTH DAKOTA AND SOUTHWEST SIOUX COUNTY IOWA. MOVEMENT WAS EAST AT 25 MILES AN HOUR. THIS DIRECTION AND SPEED WILL TAKE THESE STORMS OVER THE TOWNS OF ALCESTER AND BIG SPRINGS IN UNION COUNTY AND HAWARDEN...CHATSWORTH...MAURICE...ORANGE CITY AND ALTON IN SIOUX COUNTY IOWA...BETWEEN 400 AND 500 AM. THESE STORMS HAVE THE POTENTIAL FOR SMALL HAIL...HEAVY RAIN SHOWERS... DANGEROUS LIGHTNING AND STRONG GUSTY WINDS. RESIDENTS OF THE UNION AND SIOUX COUNTY AREA SHOULD WATCH THE WEATHER CLOSELY AND BE PREPARED TO GO TO A SAFE SHELTER IF SEVERE WEATHER SHOULD DEVELOPE. SHERLIN ....CORRECTION TO LAST PARA...<SIOUX COUNTRY REPLACES PLYMOUTH...
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 5, 4:31 AM CDT | Severe Thunderstorm Warning | FSD | Union | 38 min |
| Aug 5, 6:17 AM CDT | Severe Thunderstorm Warning | FSD | Union | 58 min |
| Aug 5, 4:49 AM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 56 min |
| Aug 5, 4:49 AM CDT | Severe Thunderstorm Warning | FSD | Sioux | 26 min |
| Aug 5, 6:45 AM CDT | Severe Thunderstorm Warning | FSD | Woodbury | 60 min |
| Aug 5, 6:45 AM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 60 min |
| Aug 5, 6:55 AM CDT | Severe Thunderstorm Warning | FSD | Monona | 65 min |
| Aug 5, 7:35 AM CDT | Severe Thunderstorm Warning | FSD | Ida | 55 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1989Every severe thunderstorm warning in 1989
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.