Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 77, NWS Des Moines, IA
NWS Des Moines, IA issued this severe thunderstorm warning at Jul 6, 1987, 3:58 PM CDT for Linn County, Iowa. It was in force for 47 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Jul 6, 1987, 3:58 PM CDT (20:58 UTC)
- Expired
- Jul 6, 1987, 4:45 PM CDT
- In force
- 47 min
- Issued by
- NWS Des Moines, IA
- Area
- Whole counties
County Linn County, IA
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 6, 3:59 PM CDT | Hail 0.75 | Linn, IA | |
| Jul 6, 4:20 PM CDT | Hail 0.75 | Linn, IA |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Peoria Regional, IL (KPIA), launched 12:00Z, 9.0 hours before the alert went out and 229 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
- NaN m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 51 m²/s²
- 0-3 km storm-relative helicity
- 86 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 062058 SVRDSM IAC113-062145- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE DES MOINES IA 358 PM CDT MON JUL 6 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 445 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTY OF EAST CENTRAL IOWA... LINN A SEVERE THUNDERSTORM WAS IN NORTHWEST LINN COUNTY OF NORTHEAST IOWA. THIS IS ABOUT 20 MILES NORTH NORTHWEST OF CEDAR RAPIDS. THIS INCLUDES THE CITIES OF CENTRAL CITY...TODDVILLE...AND CEDAR RAPIDS. THE STORM HAS BEEN PRODUCING LARGE HAIL AND LOCALLY HEAVY RAINS. THE STORM WAS MOVING SOUTHEST AROUND 20 TO 25 MILES AN HOUR. 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. IF THREATENING WEATHER APPROACHES..YOU SHOULD GO TO A SAFE PLACE IMMEDIATELY. IF SEVERE WEATHER CONDITIONS ARE OBSERVED..PLEASE ASK THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE. ADAMS/WEINBRECHT
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 6, 10:42 AM CDT, 5 hours 16 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 1041 AM CDT MON JUL 6 1987 AT 1035 AM CDT... A SMALL CLUSTER OF SHOWERS AND STRONG THUNDERSTORMS PERSISTED OVER NORTHEAST AND EAST CENTRAL IOWA...WITH THE STRONGEST STORM LOCATED ABOUT 30 MILES WEST NORTHWEST OF DUBUQUE...NEAR MANCHESTER. BRIEF HEAVY RAIN AND SOME SMALL HAIL IS STILL POSSIBLE WITH THIS STORM. WEAKER THUNDERSHOWERS WERE SCATTERED BETWEEN WATERLOO...MARSHALLTOWN AND CEDAR RAPIDS. A SMALL AREA OF LIGHT SHOWERS LINGERED OVER NORTH CENTRAL IOWA...FROM 65 MILES NORTH OF DES MOINES NEAR IOWA FALLS NORTH TO NEAR MASON CITY AND WEST TO NEAR FORT DODGE. THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 30 MILES AND HOUR. BARLOW
Special weather statement, Jul 6, 11:52 AM CDT, 4 hours 6 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE DES MOINES IA 1147 AM CDT MON JUL 6 1987 AT 1135 AM CDT... SCATTERED SHOWERS AND ISOLATED STRONG THUNDERSTORMS PERSISTED OVER THE NORTHEAST THIRD OF IOWA. THE STRONGEST STORMS WERE LOCATED 40 MILES WEST OF THE DUBUQUE AREA OR JUST SOUTHEAST OF MANCHESTER... AND 25 MILES NORTHEAST OF CEDAR RAPIDS NEAR CENTRAL CITY. BRIEF HEAVY RAIN...WIND GUSTS OF 30 TO 40 MILES AN HOUR AND SOME SMALL HAIL ARE POSSIBLE WITH THESE STORMS. LIGHTER SHOWERS WERE LOCATED NORTHWEST OF WATERLOO AROUND THE HAMPTON...IOWA FALLS AND ACKLEY AREAS. THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 25 MILES AN HOUR. BARLOW
The office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 6, 2:31 PM CDT | Severe Thunderstorm Warning | DMX | Black Hawk | 59 min |
| Jul 6, 3:22 PM CDT | Severe Thunderstorm Warning | DMX | Benton, Linn | 38 min |
| Jul 6, 3:25 PM CDT | Severe Thunderstorm Warning | DMX | Buchanan | 50 min |
| Jul 6, 4:30 PM CDT | Severe Thunderstorm Warning | DMX | Linn | 45 min |
| Jul 6, 5:16 PM CDT | Severe Thunderstorm Warning | DMX | Johnson, Linn | 44 min |
| Jul 6, 6:09 PM CDT | Severe Thunderstorm Warning | DMX | Johnson | 41 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.