Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 64, NWS Twin Cities, MN
NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 20, 1987, 9:34 PM CDT for Hennepin County, Scott County, Minnesota. It was in force for 56 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
- Jul 20, 1987, 9:34 PM CDT (02:34 UTC)
- Expired
- Jul 20, 1987, 10:30 PM CDT
- In force
- 56 min
- Issued by
- NWS Twin Cities, MN
- Area
- Whole counties
Counties Hennepin County, MN, Scott County, MN
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 20, 10:19 PM CDT | Hail 0.75 | Hennepin, MN |
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
Minneapolis, MN (KSTC), launched 00:00Z, 2.6 hours before the alert went out and 8 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
- 3871 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 860 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- 0.9
- Supercell composite
- 4.4
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KMSP 210234 SVRMSP MNC053-139-210330- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MINNEAPOLIS MN 934 PM CDT MON JUL 20 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1030 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF EAST CENTRAL MINNESOTA... EXTREME SOUTHERN HENNEPIN AND NORTHERN SCOTT AT 925 PM CDT..A SEVERE THUNDERSTORM PRODUCED GOLFBALL SIZE HAIL IN THE CHASKA AREA ABOUT 10 MILES SOUTHWEST OF DOWNTOWN MINNEAPOLIS. THIS SEVERE THUNDERSTORM WAS MOVING EAST AT 20 TO 25 MILES AN HOUR AND WILL BE AFFECTING AREAS NEAR THE CITIES OF PRIOR LAKE.. SHAKOPEE..BLOOMINGTON AND RICHFIELD. REMEMBER SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH..DESTRUCTIVE HAIL..DEADLY LIGHTNING AND VERY HEAVY RAIN. ALSO SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE A TORNADO 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. MATHEWS
The office that day
Everything else NWS Twin Cities, MN issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 7:06 PM CDT | Tornado Warning | MPX | Dakota | 24 min |
| Jul 20, 7:13 PM CDT | Tornado Warning | MPX | Anoka, Hennepin, Ramsey | 27 min |
| Jul 20, 7:14 PM CDT | Severe Thunderstorm Warning | MPX | Meeker | 61 min |
| Jul 20, 8:00 PM CDT | Severe Thunderstorm Warning | MPX | Lac qui Parle | 60 min |
| Jul 20, 8:09 PM CDT | Severe Thunderstorm Warning | MPX | Ramsey, Washington | 51 min |
| Jul 20, 9:45 PM CDT | Severe Thunderstorm Warning | MPX | Kandiyohi, Meeker | 60 min |
| Jul 20, 10:36 PM CDT | Severe Thunderstorm Warning | MPX | Carver, Hennepin | 54 min |
Nearby
Severe Thunderstorm Warnings in Minnesota, 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.