Alert archive / Minnesota / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 173, NWS Twin Cities, MN

June 20, 1998Watonwan County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jun 20, 1998, 9:54 AM CDT for Watonwan County, Minnesota. It was in force for 36 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: Jun 20, 1998, 9:54 AM CDT (14:54 UTC)
Expired: Jun 20, 1998, 10:30 AM CDT
In force: 36 min
Issued by: NWS Twin Cities, MN
Area: Whole counties

County Watonwan County, MN

The radar

The Minneapolis radar (KMPX), 128 km from the middle of the area, began a volume at 14:57 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Jun 20, 10:10 AM CDT	Hail 0.75	Ormsby, MN
Jun 20, 10:20 AM CDT	Hail 0.75	South Branch, 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jun 20, 9:15 AM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 2.9 hours before the alert went out and 126 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 18 J/kg
Mixed-layer CIN: -384 J/kg
Mixed-layer LCL: 2049 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 416 m²/s²
0-3 km storm-relative helicity: 589 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

953 
WUUS1 KMSP 201456 RRA
SVRMSP
MNC165-201530-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
954 AM CDT SAT JUN 20 1998

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES/CHANHASSEN HAS
ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WATONWAN COUNTY IN SOUTH CENTRAL MINNESOTA

* UNTIL 1030 AM CDT

* AT 955 AM CDT...DOPPLER RADAR INDICATED A SEVERE STORM WITH LARGE
  HAIL NEAR ORMSBY OR 20 MILES NORTHWEST OF FAIRMONT.  THE STORM WAS
  MOVING NORTHEAST AT 35 MPH.

* SOME LOCATIONS AFFECTED
    SOUTH BRANCH
    LEWISVILLE
    ST JAMES

THIS IS A DANGEROUS STORM...WITH LARGE HAIL.  STAY INDOORS AWAY
FROM WINDOWS.


BAP

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 20, 8:34 AM CDT	Severe Thunderstorm Warning	MPX	Martin	61 min
Jun 20, 8:40 AM CDT	Severe Thunderstorm Warning	MPX	Brown, Watonwan	65 min
Jun 20, 9:14 AM CDT	Severe Thunderstorm Warning	MPX	Nicollet, Sibley	61 min
Jun 20, 9:31 AM CDT	Severe Thunderstorm Warning	MPX	Martin	64 min
Jun 20, 9:35 AM CDT	Severe Thunderstorm Warning	MPX	Scott	40 min
Jun 20, 10:25 AM CDT	Severe Thunderstorm Warning	MPX	Watonwan	35 min
Jun 20, 11:19 AM CDT	Severe Thunderstorm Warning	MPX	Faribault, Martin	46 min
Jun 20, 12:00 PM CDT	Severe Thunderstorm Warning	MPX	Faribault	65 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1998 Every severe thunderstorm warning in 1998

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; radar from the NEXRAD Level II archive.