Alert archive / Iowa / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 39, NWS Quad Cities, IA
NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 21, 1987, 4:57 AM CDT for Cedar County, Clinton County, Scott County, Iowa. It was in force for 33 min. 1 report 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
- Aug 21, 1987, 4:57 AM CDT (09:57 UTC)
- Expired
- Aug 21, 1987, 5:30 AM CDT
- In force
- 33 min
- Issued by
- NWS Quad Cities, IA
- Area
- Whole counties
Counties Cedar County, IA, Clinton County, IA, Scott 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 |
|---|---|---|---|
| Aug 21, 4:58 AM CDT | Thunderstorm Wind 0 | Scott, 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 00:00Z, 10.0 hours before the alert went out and 156 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
- 1095 J/kg
- Mixed-layer CIN
- -45 J/kg
- Mixed-layer LCL
- 1543 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 92 m²/s²
- 0-3 km storm-relative helicity
- 231 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 6.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KMLI 210957 SVRMLI IAC163-045-031-ILC073-211030- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MOLINE IL 457 AM CDT FRI AUG 21 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 530 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF EXTREME EAST IOWA...WESTERN SCOTT...WESTERN CLINTON AND CEDAR NORTHWEST ILLINOIS...HENRY AT 455 AM CDT RADAR SHOWED A SEVERE THUNDERSTORM IN NORTHWEST HENRY COUNTY IL...10 MILES SOUTHEAST OF MOLINE. THE THUNDERSTORM WAS MOVING SOUTHEAST AT 35 TO 40 MPH. A LINE OF SEVERE THUNDERSTORMS WAS ENTERING CEDAR COUNTY IOWA... 50 MILES NORTHWEST OF THE QUAD CITIES. THIS LINE WAS MOVING TO THE SOUTHEAST AT 35 TO 40 MPH. SEVERE THUNDERSTORMS CAN PRODUCE ANY OR ALL OF THE FOLLOWING... DAMAGING WINDS OF 60 MPH OR MORE...LARGE HAIL...DEADLY LIGHTNING ...AND HEAVY RAINS THAT CAN QUICKLY FLOOD LOW LYING AREAS. PEOPLE IN THE PATH OF THIS STORM SHOULD TAKE COVER IMMEDIATELY. SEVERE THUNDERSTORMS CAN AND SOMETIMES DO PRODDUCE TORNADOES... SO BE ON THE LOOKOUT AND BE PREPARED TO MOVE TO A PLACE OF SAFETY IF ONE IS SPOTTED. IF TIME PERMITS...ASK THE NEAREST LAW ENFORCEMENT AGEN[CY TO RELAY YOUR REPORT OF SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE. ATTN ISP 7 AND 1 KRAEMER
The office that day
Everything else NWS Quad Cities, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 12:32 AM CDT | Severe Thunderstorm Warning | DVN | Jones | 43 min |
| Aug 21, 12:39 AM CDT | Severe Thunderstorm Warning | DVN | Cedar | 21 min |
| Aug 21, 1:02 AM CDT | Severe Thunderstorm Warning | DVN | Cedar, Muscatine | 38 min |
| Aug 21, 1:49 AM CDT | Severe Thunderstorm Warning | DVN | Scott | 26 min |
| Aug 21, 2:18 AM CDT | Severe Thunderstorm Warning | DVN | Scott | 42 min |
| Aug 21, 3:31 AM CDT | Severe Thunderstorm Warning | DVN | Scott | 29 min |
| Aug 21, 4:01 AM CDT | Severe Thunderstorm Warning | DVN | Scott | 59 min |
| Aug 21, 5:28 AM CDT | Severe Thunderstorm Warning | DVN | Scott | 47 min |
| Aug 21, 5:53 AM CDT | Flash Flood Warning | DVN | Scott | 3 hr |
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.