Alert archive / Iowa / Severe Thunderstorm Warnings in 1994
Severe Thunderstorm Warning 151, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 31, 1994, 5:31 PM CDT for Winnebago County, Iowa. It was in force for 29 min.
The area
The counties it named.
The facts
- Issued
- Jul 31, 1994, 5:31 PM CDT (22:31 UTC)
- Expired
- Jul 31, 1994, 6:00 PM CDT
- In force
- 29 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Winnebago County, IA
The nearest sounding before it
Minneapolis, MN (KSTC), launched 12:00Z, 10.5 hours before the alert went out and 164 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
- 4 J/kg
- Mixed-layer CIN
- -306 J/kg
- Mixed-layer LCL
- 1222 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 87 m²/s²
- 0-3 km storm-relative helicity
- 153 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KALO 312232 RRA SVRALO IAC189-312300- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE WATERLOO IA 531 PM CDT SUN JUL 31 1994 THE NATIONAL WEATHER SERVICE IN WATERLOO HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 600 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN NORTH CENTRAL IOWA ...SOUTHERN WINNEBAGO COUNTY AT 530 PM CDT...NWS RADAR INDICATED A POSSIBLY SEVERE THUNDERSTORM DIRECTLY OVER FOREST CITY...OR 15 MILES NORTHWEST OF MASON CITY...AND IS MOVING EAST AT 25 MILES AN HOUR. THIS STORM WILL AFFECT FOREST CITY AND AREAS EAST OF FOREST CITY THROUGH 600 PM. IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A REINFORCED BUILDING. STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. DEWALD
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 31, 4:24 PM CDT, 1 hour 7 minutes before
IAZ006>011-016>019-026>029-038>040-312225- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WATERLOO IA 422 PM CDT SUN JUL 31 1994 ...SEVERE THUNDERSTORM WATCH FOR NORTHEAST AND NORTH CENTRAL IOWA... A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR ALL OF NORTHEAST AND NORTH CENTRAL IOWA THROUGH 10 PM. AT 420 PM RADAR INDICATED THUNDERSTORMS WERE RAPIDLY FORMING ALONG A SURFACE BOUNDARY WHICH WAS LOCATED FROM ROCHESTER MINNESOTA SOUTHWEST INTO THE MASON CITY AREA. THESE STORMS HAVE SHOWN RAPID GROWTH DURING THE PAST HOUR AS THEY HAVE CONTINUED TO BUILD TO THE SOUTHWEST. FROM 430 THROUGH 530 PM PEOPLE IN THE NORTHWOOD...MANLY...GARNER AND MASON CITY AREAS SHOULD KEEP A WATCHFUL EYE ON THE SKY. STORMS COULD RAPIDLY FORM AND BECOME SEVERE WITH LITTLE WARNING. PEOPLE IN THE OSAGE...ST ANSGAR...NORA SPRINGS AND ROCKFORD AREAS CAN EXPECT THUNDERSTORMS AFTER 5 PM. AT SIGNS OF AN IMPENDING STORM...TOWERING THUNDERHEADS...DARKENING SKIESZ...LIGHTNING AND INCREASING WINDS...MOVE TO A PLACE OF SAFETY. TUNE IN NOAA WEATHER RADIO OR YOUR LOCAL RADIO OR TV STATION FOR THE LATEST WEATHER INFORMATION. PABST
Special weather statement, Jul 31, 4:47 PM CDT, 44 minutes before
IAZALL-312245- SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 4 30 PM CDT SUN JUL 31 1994 A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PORTIONS OF NORTHERN AND CENTRAL IOWA UNTIL 10 PM THIS SUNDAY EVENING... AT 4 30 PM CDT...AN AREA OF INTENSE THUNDERSTORMS HAD DEVELOPED IN SOUTH CENTRAL AND SOUTHEAST MINNESOTA. A FEW SHOWER AND THUNDERSTORMS OF LESSER INTENSITY EXTENDED INTO NORTH CENTRAL IOWA AND WERE LOCATED NEAR BUFFALO CENTER AND NORTHWOOD. MOVEMENT OF THE THUNDERSTORMS WAS NOT DETERMINED DUE TO THEIR RECENT DEVELOPMENT. SCOTT
Special weather statement, Jul 31, 5:15 PM CDT, 16 minutes before
IAZ006>011-016>019-026>029-038>040-312320- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WATERLOO IA 515 PM CDT SUN JUL 31 1994 ...SEVERE THUNDERSTORMS NORTHWEST AND NORTHEAST OF MASON CITY... AT 510 PM RADAR INDICATED TWO AREAS OF THUNDERSTORMS. A SEVERE THUNDERSTORM WAS MOVING THROUGH SOUTHERN WINNEBAGO COUNTY... 20 MILES NORTHWEST OF MASON CITY AND ABOUT 5 MILES WEST OF FOREST CITY . THIS STORM SHOULD AFFECT THE FOREST CITY AREA BETWEEN 515 AND 530 PM. ANOTHER AREA OF SHOWERS AND THUNDERSTORMS WERE PART OF A LINE WHICH STRETCHED FROM EAST OF ROCHESTER TO JUST NORTH OF OSAGE OR 25 MILES NORTHEAST OF MASON CITY. ALL OF THESE STORMS ARE MOVING TO THE EAST AT 20 MILES AN HOUR. STORMS WILL MOVE THROUGH THE NORTHERN TIER OF COUNTIES DURING THE LATE AFTERNOON AND EARLY EVENING HOURS AND AFFECT THE MASON CITY...OSAGE...CRESCO AND DECORAH AREAS. THESE STORMS HAVE FORMED VERY RAPIDLY AND ARE CAPABLE OF PRODUCING SEVERE WEATHER WITH LITTLE WARNING. AT SIGNS OF AN IMPENDING STORM...TOWERING THUNDERHEADS...DARKENING SKIES...LIGHTNING AND INCREASING WINDS...MOVE TO A PLACE OF SAFETY. TUNE IN NOAA WEATHER RADIO OR YOUR LOCAL RADIO OR TV STATION FOR THE LATEST WEATHER INFORMATION. PABST
Special weather statement, Jul 31, 5:17 PM CDT, 14 minutes before
IAZ006>011-016>019-026>029-038>040-312320- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WATERLOO IA 515 PM CDT SUN JUL 31 1994 ...SEVERE THUNDERSTORMS NORTHWEST AND NORTHEAST OF MASON CITY... AT 510 PM RADAR INDICATED TWO AREAS OF THUNDERSTORMS. A SEVERE THUNDERSTORM WAS MOVING THROUGH SOUTHERN WINNEBAGO COUNTY... 20 MILES NORTHWEST OF MASON CITY AND ABOUT 5 MILES WEST OF FOREST CITY . THIS STORM SHOULD AFFECT THE FOREST CITY AREA BETWEEN 515 AND 530 PM. ANOTHER AREA OF SHOWERS AND THUNDERSTORMS WERE PART OF A LINE WHICH STRETCHED FROM EAST OF ROCHESTER TO JUST NORTH OF OSAGE OR 25 MILES NORTHEAST OF MASON CITY. ALL OF THESE STORMS ARE MOVING TO THE EAST AT 20 MILES AN HOUR. STORMS WILL MOVE THROUGH THE NORTHERN TIER OF COUNTIES DURING THE LATE AFTERNOON AND EARLY EVENING HOURS AND AFFECT THE MASON CITY...OSAGE...CRESCO AND DECORAH AREAS. THESE STORMS HAVE FORMED VERY RAPIDLY AND ARE CAPABLE OF PRODUCING SEVERE WEATHER WITH LITTLE WARNING. AT SIGNS OF AN IMPENDING STORM...TOWERING THUNDERHEADS...DARKENING SKIES...LIGHTNING AND INCREASING WINDS...MOVE TO A PLACE OF SAFETY. TUNE IN NOAA WEATHER RADIO OR YOUR LOCAL RADIO OR TV STATION FOR THE LATEST WEATHER INFORMATION. PABST
Special weather statement, Jul 31, 5:23 PM CDT, 8 minutes before
IAZALL-312330- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 523 PM CDT SUN JUL 31 1994 ...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 10 PM CDT FOR NORTHERN AND CENTRAL IOWA... AT 525 PM CDT SEVERE THUNDERSTORMS WERE MOVING ACROSS EXTREME SOUTHERN MINNESOTA...NEAR THE IOWA BORDER. THESE STORMS PRODUCED BASEBALL SIZED HAIL AND WERE MOVING TO THE SOUTHEAST AT 15 MILES AN HOUR. THE STORMS WILL CROSS THE IOWA BORDER BY 6 PM CDT AND WILL MOVE TOWARDS THE CITIES OF MASON CITY AND CHARLES CITY. WEATHER SERVICE DOPPLER RADAR ALSO SHOWED THUNDERSTORMS MOVING OVER FOREST CITY IN FLOYD COUNTY...IN NORTH CENTRAL IOWA. THIS STORM WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. PEOPLE IN NORTHERN AND CENTRAL IOWA SHOULD KEEP AN EYE TO THE SKY AND BE PREPARED TO SEEK SHELTER SHOULD THREATENING WEATHER APPROACH. FAB
Special weather statement, Jul 31, 5:24 PM CDT, 7 minutes before
IAZALL-312330- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DES MOINES IA 523 PM CDT SUN JUL 31 1994 ...A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 10 PM CDT FOR NORTHERN AND CENTRAL IOWA... AT 525 PM CDT SEVERE THUNDERSTORMS WERE MOVING ACROSS EXTREME SOUTHERN MINNESOTA...NEAR THE IOWA BORDER. THESE STORMS PRODUCED BASEBALL SIZED HAIL AND WERE MOVING TO THE SOUTHEAST AT 15 MILES AN HOUR. THE STORMS WILL CROSS THE IOWA BORDER BY 6 PM CDT AND WILL MOVE TOWARDS THE CITIES OF MASON CITY AND CHARLES CITY. WEATHER SERVICE DOPPLER RADAR ALSO SHOWED THUNDERSTORMS MOVING OVER FOREST CITY IN FLOYD COUNTY...IN NORTH CENTRAL IOWA. THIS STORM WAS MOVING SOUTHEAST AT 15 MILES AN HOUR. PEOPLE IN NORTHERN AND CENTRAL IOWA SHOULD KEEP AN EYE TO THE SKY AND BE PREPARED TO SEEK SHELTER SHOULD THREATENING WEATHER APPROACH. FAB
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 31, 7:55 AM CDT | Severe Thunderstorm Warning | DMX | Mitchell | 35 min |
| Jul 31, 4:54 PM CDT | Severe Thunderstorm Warning | DMX | Winnebago | 36 min |
| Jul 31, 5:26 PM CDT | Severe Thunderstorm Warning | DMX | Mitchell | 34 min |
| Jul 31, 6:02 PM CDT | Severe Thunderstorm Warning | DMX | Hancock | 28 min |
| Jul 31, 6:16 PM CDT | Severe Thunderstorm Warning | DMX | Mitchell, Worth | 44 min |
| Jul 31, 6:33 PM CDT | Tornado Warning | DMX | Mitchell | 27 min |
| Jul 31, 6:41 PM CDT | Severe Thunderstorm Warning | DMX | Hancock, Winnebago | 34 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.