Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 101, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 24, 1987, 6:40 PM CDT for Webster County, Iowa. It was in force for 30 min.
The area
The counties it named.
The facts
- Issued
- Jul 24, 1987, 6:40 PM CDT (23:40 UTC)
- Expired
- Jul 24, 1987, 7:10 PM CDT
- In force
- 30 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Webster 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 12:00Z, 11.7 hours before the alert went out and 219 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 3637 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- 46 m²/s²
- 0-3 km storm-relative helicity
- 109 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 KDSM 242340 SVRDSM IAC187-250030- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 640 PM CDT FRI JUL 24 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 730 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF CENTRAL IOWA... SOUTHERN WEBSTER AT 635 PM CDT A SEVERE THUNDERSTORMS AS INDICTAED BY RADAR WAS LOCATED WEST OF GOWRIE IOWA JUST 20 MILES SOUTHWEST OF FORT DODGE. THE STORM WAS MOVING EAST AT 25 TO 30 MILES AN HOUR. TOWNS IN THE PATH OF THIS STORM INCLUDE GOWRIE...HARCOURT AND DAYTON. REMEMBER..A SEVERE THUNDERSTORM CAN PRODUCE DAMAGING WINDS IN EXCESS OF 60 MPH..LARGE HAIL..DEADLY LIGHTNING..AND HEAVY RAINS THAT CAN QUICKLY FLOOD LOW LYING AREAS. PEOPLE IN THE PATH OF THIS STORM SHOULD TAKE APPROPRIATE ACTION IMMEDIATELY. THESE STORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING..SO BE ON THE LOOKOUT AND BE PREPARED TO MOVE TO A PLACE OF SAFETY IF ONE IS SPOTTED. FORSTER/KS
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 24, 3:38 PM CDT, 3 hours 2 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 435 PM CDT FRI JUL 24 1987 ...SEVERE THUNDERSTORM WATCH FOR CENTRAL AND NORTHWEST IOWA UNTIL 8 PM THIS EVENING... AT 425 PM...SHOWERS HAD ENTERED NORTHWEST IOWA...JUST NORTH OF SIOUX CITY. STRONG THUNDERSTORMS REMAIN TO THE WEST OF IOWA AT THIS TIME. THE SHOWERS AND STORMS WERE MOVING EAST AT 20 MILES AN HOUR. KS
Special weather statement, Jul 24, 4:38 PM CDT, 2 hours 2 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 535 PM CDT FRI JUL 24 1987 ...SEVERE THUNDERSTORM WATCH FOR CENTRAL AND NORTHWEST IOWA UNTIL 8 PM THIS EVENING... AT 530 PM...SHOWERS AND THUNDERSHOWERS CONTINUED TO SPREAD INTO NORTHWEST IOWA. ALL RAINFALL WAS NORTH AND WEST OF A SIOUX CITY/ IOWA GREAT LAKES LINE. INTENSE THUNDERSTORMS WERE 70 MILES WEST OF THE IOWA/NEBRASKA BORDER. THE SHOWERS A&ND STORMS WERE MOVING SOUTHEAST AT 25 MILES AN HOUR. KS
Special weather statement, Jul 24, 5:39 PM CDT, 1 hour 1 minute before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 535 PM CDT FRI JUL 24 1987 ...SEVERE THUNDERSTORM WATCH FOR CENTRAL AND NORTHWEST IOWA UNTIL 8 PM THIS EVENING... NO SEVERE WEATHER HAS BEEN REPORTED IOWA IN BETWEEN 435 - 535 PM. AT 530 PM...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WERE IN NORTHWEST IOWA. ALL RAINFALL WAS NORTHWEST OF A CARROLL/FORT DODGE LINE. THE STRONGEST STORM WAS BETWEEN IDA GROVE AND HOLSTEIN...50 MILES EAST OF SIOUX CITY. OTHER THUNDERSTORMS WERE NEAR ROCKWELL CITY AND LAKE VIEW...80 MILES EAST OF SIOUX CITY. STRONGER THUNDERSTORMS REMAIN TO THE WEST OF IOWA...IN NORTHEAST NEBRASKA. / THE SHOWERS AND STORMS WERE MOVING SOUTHEAST AT 25 MILES AN HOUR. KS
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 24, 6:00 PM CDT | Severe Thunderstorm Warning | DMX | Calhoun, Carroll, Greene | 60 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1987Every severe thunderstorm warning in 1987
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.