Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 116, NWS Twin Cities, MN
NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 21, 1987, 2:23 AM CDT for Freeborn County, Steele County, Minnesota. It was in force for 22 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, 2:23 AM CDT (07:23 UTC)
- Expired
- Aug 21, 1987, 2:45 AM CDT
- In force
- 22 min
- Issued by
- NWS Twin Cities, MN
- Area
- Whole counties
Counties Freeborn County, MN, Steele 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 |
|---|---|---|---|
| Aug 21, 2:25 AM CDT | Hail 1.75 | Steele, 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, 7.4 hours before the alert went out and 114 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
- 1057 J/kg
- Mixed-layer CIN
- -24 J/kg
- Mixed-layer LCL
- 1129 m above ground
- 0-6 km bulk shear
- 48 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 89 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.7
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KRST 210723 SVRRST MNC047-147-210745- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE ROCHESTER MN 223 AM CDT FRI AUG 21 1987 THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 245 AM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF SOUTH CENTRAL MINNESOTA...NORTHEAST FREEBORN AND STEELE THIS WARNING INCLUDES THE CITIES OF OWATONNA...BLOOMING PRAIRIE AND MAPLE ISLAND. AT 2 15 AM...RADAR INDICATED A SEVERE THUNDERSTORM 40 MILES WEST OF ROCHESTER OVER WESTERN STEELE COUNTY...MOVING TO THE SOUTHEAST AT 45 MILES AN HOUR. REMEMBER SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MPH..DESTRUCTIVE HAIL..DEADLY4 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.
The office that day
Everything else NWS Twin Cities, MN issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 2:12 AM CDT | Severe Thunderstorm Warning | MPX | Waseca | 18 min |
| Aug 21, 2:39 AM CDT | Severe Thunderstorm Warning | MPX | Dodge, Mower | 36 min |
| Aug 21, 1:55 PM CDT | Severe Thunderstorm Warning | MPX | Todd | 65 min |
| Aug 21, 2:25 PM CDT | Severe Thunderstorm Warning | MPX | Morrison | 65 min |
| Aug 21, 3:25 PM CDT | Severe Thunderstorm Warning | MPX | Chippewa, Lac qui Parle | 60 min |
| Aug 21, 3:55 PM CDT | Severe Thunderstorm Warning | MPX | Yellow Medicine | 50 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.