Alert archive / Iowa / Severe Thunderstorm Warnings in 1994
Severe Thunderstorm Warning 142, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Sep 20, 1994, 7:39 PM CDT for Lyon County, Iowa. It was in force for 36 min.
The area
The counties it named.
The facts
- Issued
- Sep 20, 1994, 7:39 PM CDT (00:39 UTC)
- Expired
- Sep 20, 1994, 8:15 PM CDT
- In force
- 36 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Lyon County, IA
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 0.7 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
- 190 J/kg
- Mixed-layer CIN
- -98 J/kg
- Mixed-layer LCL
- 2268 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 90 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 210040 RRA SVRFSD IAC119-210115- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 739 PM CDT TUE SEP 20 1994 THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 815 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN NORTHWEST IOWA ...EASTERN LYON COUNTY AT 737 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM 3 MILES SOUTH OF GEORGE IOWA MOVING EAST AT 25 MPH. SOME CITIES EFFECTED BETWEEN 740 PM AND 820 PM ARE GEORGE AND LITTLE ROCK. 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.
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, Sep 20, 5:40 PM CDT, 1 hour 59 minutes before
IAZ013-210015- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX CITY IA 540 PM CDT TUE SEP 20 1994 ...SCATTERED THUNDERSTORMS WILL OCCUR NORTHEAST OF SIOUX CITY... AT 538 PM CDT A THUNDERSTORM WAS LOCATED 60 MILES NORTHEAST OF SIOUX CITY NEAR SHELDON IOWA. MOVEMENT WAS EAST AT 30 MILES AN HOUR. THE THUNDERSTORM WILL MOVE NEAR PRIMGHAR AND HARTLEY IOWA BETWEEN 600 AND 615 PM. THE THUNDERSTORM WILL PRODUCE LOCALLY HEAVY RAIN...DANGEROUS LIGHTNING AND SMALL HAIL. HOPPES/GREIF
Special weather statement, Sep 20, 6:01 PM CDT, 1 hour 38 minutes before
IAZ013-210015- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX CITY IA 601 PM CDT TUE SEP 20 1994 ...SOME HAIL WAS OCCURING NORTHEAST OF SIOUX CITY... AT 548 PM CDT MARBLE SIZE FELL 60 MILES NORTHEAST OF SIOUX CITY AT RITTER IOWA. MOVEMENT WAS EAST AT 30 MILES AN HOUR. THE THUNDERSTORMS WILL MOVE NEAR MONETA IOWA...70 MILES NORTHEAST OF SIOUX CITY BETWEEN 630 AND 645 PM. THE THUNDERSTORM WILL PRODUCE LOCALLY HEAVY RAIN...DANGEROUS LIGHTNING AND HAIL. HOPPES/GREIF
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 20, 7:29 PM CDT | Severe Thunderstorm Warning | FSD | Sioux | 31 min |
| Sep 20, 8:00 PM CDT | Severe Thunderstorm Warning | FSD | Lyon | 30 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.