Alert archive / Minnesota / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 284, NWS Twin Cities, MN

July 20, 1998Redwood County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 20, 1998, 10:19 AM CDT for Redwood County, Minnesota. It was in force for 56 min. 5 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 20, 1998, 10:19 AM CDT (15:19 UTC)
Expired
Jul 20, 1998, 11:15 AM CDT
In force
56 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Redwood County, MN

The radar

The Minneapolis radar (KMPX), 142 km from the middle of the area, began a volume at 15:20 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

TimeReportWhereRemark
Jul 20, 10:30 AM CDTHail 1.75Milroy, MNLarge swath of hail damage across southern Redwood county.
Jul 20, 10:49 AM CDTHail 0.75Lamberton, MN
Jul 20, 10:55 AM CDTThunderstorm Wind 52Sanborn, MNRoof ripped off bldg. Severe hail damage to areas across southern Redwood county.
Jul 20, 11:00 AM CDTThunderstorm Wind 65Clements, MNPower lines down. Estimated windspeed.
Jul 20, 11:00 AM CDTThunderstorm Wind 65Clements, MNTrees blown onto houses and vehicles. Estimated windspeed.

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 nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 3.3 hours before the alert went out and 140 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-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 1998-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 1998-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 63 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2372 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
63 m²/s²
0-3 km storm-relative helicity
103 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 201519 RRA
SVRMSP
MNC127-201615-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1019 AM CDT MON JUL 20 1998

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

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN REDWOOD COUNTY IN SOUTHWESTERN MINNESOTA

* UNTIL 1115 AM CDT

* AT 1017 AM CDT...DOPPLER RADAR INDICATED A SEVERE STORM WITH LARGE
  HAIL 10 MILES SOUTH OF MARSHALL.  THE STORM WAS MOVING EAST AT 35
  MPH.

* SOME LOCATIONS AFFECTED
    WALNUT GROVE
    LAMBERTON
    REVERE
    SANBORN

THIS IS A DANGEROUS STORM.  STAY INDOORS AWAY FROM WINDOWS.


WH

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 10:51 AM CDTSevere Thunderstorm WarningMPXBrown64 min
Jul 20, 11:35 AM CDTSevere Thunderstorm WarningMPXBlue Earth, Nicollet60 min
Jul 20, 11:43 AM CDTTornado WarningMPXNicollet32 min
Jul 20, 12:05 PM CDTSevere Thunderstorm WarningMPXLe Sueur40 min
Jul 20, 12:22 PM CDTSevere Thunderstorm WarningMPXRice63 min
Jul 20, 12:51 PM CDTSevere Thunderstorm WarningMPXGoodhue64 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1998Every 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.