Alert archive / Iowa / Severe Thunderstorm Warnings in 1994
Severe Thunderstorm Warning 75, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 30, 1994, 10:20 PM CDT for Osceola County, Iowa. It was in force for 55 min.
The area
The counties it named.
The facts
- Issued
- Jun 30, 1994, 10:20 PM CDT (03:20 UTC)
- Expired
- Jun 30, 1994, 11:15 PM CDT
- In force
- 55 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Osceola County, IA
The nearest sounding before it
Minneapolis, MN (KSTC), launched 00:00Z, 3.3 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
- 2237 J/kg
- Mixed-layer CIN
- -42 J/kg
- Mixed-layer LCL
- 1140 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 266 m²/s²
- 0-3 km storm-relative helicity
- 383 m²/s²
- Significant tornado parameter
- 4.4
- Supercell composite
- 12.4
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS1 KFSD 010323 RRA SVRFSD IAC143-010415- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 1020 PM CDT THU JUN 30 1994 THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1115 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN NORTHWEST IOWA ...OSCEOLA COUNTY AT 1020 PM CDT RADAR SHOWED SEVERE THUNDERSTORMS 10 MILES SOUTHWEST OF WORTHINGTON NEAR BIGELOW MINNESOTA AND 5 MILES SOUTH OF WORTHINGTON MINNESOTA. THE THUNDERSTORMS WERE MOVING SOUTHEAST AT 25 MPH. THIS IS A DANGEROUS STORM. IF YOR ARE IN ITS PATH...PREPARE IMMEDIATELY FOR WINDS IN EXCESS OF 55 MPH...DESTRUCTIVE HAIL...AND DEADLY LIGHTNING. A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA. REMEMBER...SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING SO BE ON THE LOOKOUT. BLOOM
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, Jun 30, 8:55 PM CDT, 1 hour 25 minutes before
MNZ080-081-089-090-010400Z- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 845 PM CDT THU JUN 30 1994 ...SEVERE THUNDERSTORM WATCH SOUTHWEST MINNESOTA UNTIL 11 PM... A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR SOUTHWEST MINNESOTA COUNTIES OF COTTONWOOD...MURRAY...NOBLES AND JACKSON UNTIL 11PM THIS THURSDAY EVENING. AT 830 PM A LINE OF THUNDERSTORMS WAS BEGINNING TO DEVELOP 10 MILES EAST OF PIPESTONE TO 25 MILES SOUTH OF REDWOOD FALLS. THESE THUNDERSTORMS ARE EXPECTED TO MOVE SOUTHEAST. LARGE HAIL...DAMAGING WINDS...PERIODS OF VERY HEAVY RAIN AND DANGEROUS CLOUD TO GROUND LIGHTNING ARE POSSIBLE WITH THESE THUNDERSTORMS AS THEY CONTINUE TO DEVELOP. RESIDENTS IN AREAS AROUND SLAYTON...FULDA...MOUNTAIN LAKE AND JEFFERS SHOULD BE PREPARED FOR THIS ADVERSE WEATHER. THE DEVELOPING THUNDERSTORMS SHOULD BE IN THESE AREAS BEFORE 930 PM. BLOOM BLOOM
Special weather statement, Jun 30, 9:50 PM CDT, 30 minutes before
SDZ069-010330- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 945 PM CDT THU JUN 30 1994 ...A STRONG THUNDERSTORM IN SOUTHEAST SOUTH DAKOTA... AT 935 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A STRONG THUNDERSTORM 10 MILES WEST OF YANKTON IN YANKTON COUNTY. THIS STORM WAS MOVING SOUTHEAST AT 20 MILES AN HOUR AND IS EXPECTED TO MOVE ACROSS INTO NEBRASKA BY 1030 PM CDT. AT 937 PM CDT QUARTER TO GOLF BALL SIZE HAIL WAS REPORTED 9 MILES WEST OF YANKTON. THE STORM HAS WEAKENED BUT MAY CONTINUE TO BRING BRIEF HEAVY RAIN...GUSTY WINDS...AND SMALL HAIL. IF YOU ARE IN THE PATH OF THIS STORM PLEASE TAKE SHELTER IN A REINFORCED SHELTER. MURTHA
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 11:12 PM CDT | Severe Thunderstorm Warning | FSD | O'Brien | 63 min |
| Jul 1, 12:17 AM CDT | Severe Thunderstorm Warning | FSD | O'Brien | 21 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.