Alert archive / Iowa / Severe Thunderstorm Warnings in 1994
Severe Thunderstorm Warning 77, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 1, 1994, 12:17 AM CDT for O'Brien County, Iowa. It was in force for 21 min.
The area
The counties it named.
The facts
- Issued
- Jul 1, 1994, 12:17 AM CDT (05:17 UTC)
- Expired
- Jul 1, 1994, 12:38 AM CDT
- In force
- 21 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County O'Brien County, IA
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 5.3 hours before the alert went out and 206 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
- 2247 J/kg
- Mixed-layer CIN
- -143 J/kg
- Mixed-layer LCL
- 1586 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 39 m²/s²
- 0-3 km storm-relative helicity
- 193 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS1 KSUX 010518 RRA SVRSUX IAC141-010545- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX CITY IA 1217 AM CDT FRI JUL 1 1994 THE NATIONAL WEATHER SERVICE IN SIOUX CITY HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1245 AM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN NORTHWEST IOWA ...SOUTHERN OBRIEN COUNTY AT 1217 AM CDT RADAR INDICATED A SEVERE THUNDERSTORM 45 MILES NORTHEAST OF SIOUX CITY OR WEST OF PAULLINA IOWA. MOVEMENT WAS SOUTHEAST AT 20 MILES AN HOUR. THE THUNDERSTORMS WILL MOVE OUT OBRIEN COUNTY BETWEEN 1230 AND 1245 AM. A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA. REMEMBER...SEVERE THUNDERSTORMS CAN PRODUCE TORNADOES WITHOUT WARNING. IF A TORNADO IS SIGHTED GO TO AN INTERIOR ROOM ON THE LOWEST FLOOR. ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING OR GET INTO A DITCH OR DEPRESSION...COVER YOUR HEAD WITH 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
Local storm report, Jun 30, 11:37 PM CDT, 40 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1137 PM CDT THU JUN 30 1994
STORM DATA FOR THURSDAY JUNE 30 1994
TIME COUNTY...LOCATION AND STATE CHARACTER OF STORM...DAMAGE
.......................................................................
937 PM CDT YANKTON...9 W YANKTON SD QUARTER TO GOLF BALL SIZE
HAIL
940 PM CDT COTTONWOOD...MTN LAKE MN PEA SIZE HAIL
947 PM CDT JACKSON...HERON LAKE MN DIME SIZE HAIL..HVY RAIN
950 PM CDT NRN JACKSON/SRN COTTONWOOD MN PEA SIZE HAIL...HVY RAIN
1045 PM CDT NE OSCEOLA...HARRIS IA 1 INCH SIZE HAILLocal storm report, Jun 30, 11:38 PM CDT, 39 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1137 PM CDT THU JUN 30 1994
STORM DATA FOR THURSDAY JUNE 30 1994
TIME COUNTY...LOCATION AND STATE CHARACTER OF STORM...DAMAGE
.......................................................................
937 PM CDT YANKTON...9 W YANKTON SD QUARTER TO GOLF BALL SIZE
HAIL
940 PM CDT COTTONWOOD...MTN LAKE MN PEA SIZE HAIL
| 947 PM CDT JACKSON...HERON LAKE MN DIME SIZE HAIL..HVY RAIN
950 PM CDT NRN JACKSON/SRN COTTONWOOD MN PEA SIZE HAIL...HVY RAIN
1045 PM CDT NE OSCEOLA...HARRIS IA 1 INCH SIZE HAILLocal storm report, Jun 30, 11:40 PM CDT, 37 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SIOUX CITY IA
1140 PM CDT THU JUN 30 1994
TIME EVENT LOCATION-CITY AND COUNTY
1124 PM CDT GOLFBALL SIZE HAIL SHELDON AIRPORT - NORTH OF SHELDON
IOWA - OBRIEN COUNTY
HOPPESLocal storm report, Jun 30, 11:40 PM CDT, 37 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SIOUX CITY IA
1140 PM CDT THU JUN 30 1994
TIME EVENT LOCATION-CITY AND COUNTY
1124 PM CDT GOLFBALL SIZE HAIL SHELDON AIRPORT - NORTH OF SHELDON
IOWA - OBRIEN COUNTY
HOPPESSpecial weather statement, Jul 1, 12:07 AM CDT, 10 minutes before
IAZ013-010610- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX CITY IA 1207 AM CDT FRI JUL 1 1994 ...THUNDERSTORMS CONTINUE MOVING THROUGH OBRIEN COUNTY IOWA... AT 1203 AM CDT THUNDERSTORMS EXTENDED 45 TO 65 MILES NORTHEAST OF SIOUX CITY ACROSS OBRIEN COUNTY IOWA. MOVEMENT WAS SOUTHEAST AT 20 MILES AN HOUR. THE THUNDERSTORMS WILL EXTEND FROM GERMANTOWN TO CALUMET IOWA IN SOUTHERN OBRIEN COUNTY BETWEEN 1215 AND 1230 AM. A TORNADO WATCH REMAINS IN EFFECT UNTIL 3AM FRIDAY MORNING. IF YOU ARE OUTDOORS...MOVE TO A PLACE OF SHELTER IMMEDIATELY IF A STORM APPROACHES. MOTORISTS SHOULD REMAIN ALERT FOR REDUCED VISIBILITIES DURING DOWNPOURS OF RAIN. STREETS MAY FLOOD QUICKLY. HOPPES
Special weather statement, Jul 1, 12:07 AM CDT, 10 minutes before
IAZ013-010610- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX CITY IA 1207 AM CDT FRI JUL 1 1994 ...THUNDERSTORMS CONTINUE MOVING THROUGH OBRIEN COUNTY IOWA... AT 1203 AM CDT THUNDERSTORMS EXTENDED 45 TO 65 MILES NORTHEAST OF SIOUX CITY ACROSS OBRIEN COUNTY IOWA. MOVEMENT WAS SOUTHEAST AT 20 MILES AN HOUR. THE THUNDERSTORMS WILL EXTEND FROM GERMANTOWN TO CALUMET IOWA IN SOUTHERN OBRIEN COUNTY BETWEEN 1215 AND 1230 AM. A TORNADO WATCH REMAINS IN EFFECT UNTIL 3AM FRIDAY MORNING. IF YOU ARE OUTDOORS...MOVE TO A PLACE OF SHELTER IMMEDIATELY IF A STORM APPROACHES. MOTORISTS SHOULD REMAIN ALERT FOR REDUCED VISIBILITIES DURING DOWNPOURS OF RAIN. STREETS MAY FLOOD QUICKLY. HOPPES
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 10:20 PM CDT | Severe Thunderstorm Warning | FSD | Osceola | 55 min |
| Jun 30, 11:12 PM CDT | Severe Thunderstorm Warning | FSD | O'Brien | 63 min |
| Jul 1, 12:25 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee | 65 min |
| Jul 1, 1:26 AM CDT | Severe Thunderstorm Warning | FSD | Monona, Woodbury | 52 min |
| Jul 1, 1:26 AM CDT | Severe Thunderstorm Warning | FSD | Ida | 64 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1994Every severe thunderstorm warning in 1994
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.