Alert archive / Minnesota / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 90, NWS Sioux Falls, SD

July 25, 1997Lyon County, Minnesota

NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 25, 1997, 12:57 AM CDT for Lyon County, Minnesota. It was in force for 48 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 25, 1997, 12:57 AM CDT (05:57 UTC)
Expired
Jul 25, 1997, 1:45 AM CDT
In force
48 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Lyon County, MN

What was reported inside it

TimeReportWhereRemark
Jul 25, 1:25 AM CDTThunderstorm Wind 61Cottonwood, 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.

IssuedProductOfficeLasted
Jul 24, 10:00 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 6.0 hours before the alert went out and 184 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 00:00Z on 1997-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 870 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 1997-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 square meters per square second.1939Sfc1 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
870 J/kg
Mixed-layer CIN
-71 J/kg
Mixed-layer LCL
783 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
92 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 KFSD 250558 RRA
SVRFSD
MNC083-250645-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1257 AM CDT FRI JUL 25 1997

* SEVERE THUNDERSTORM WARNING FOR
  NORTHERN LYON COUNTY IN SOUTHWESTERN MINNESOTA

* UNTIL 145 AM CDT
 
* SOME AREAS AFFECTED
  GHENT                    AROUND 1255 AM CDT
  MARSHALL                 AROUND 110 AM CDT
  GREEN VALLEY             AROUND 115 AM CDT
  DUDLEY                   AROUND 125 AM CDT
  COTTONWOOD               AROUND 125 AM CDT

* AT 1253 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A SEVERE THUNDERSTORM 10 MILES NORTHWEST OF MARSHALL  OR 3 MILES
  NORTHWEST OF GHENT MOVING EAST AT 25 MPH.
 
REMEMBER...LIGHTNING MAY STRIKE WELL AWAY FROM THE PARENT CLOUD.
PRECAUTIONS SHOULD BE TAKEN EVEN THOUGH THE THUNDERSTORM IS NOT
DIRECTLY OVERHEAD.

 JCV

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sioux Falls, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 24, 8:32 PM CDT, 4 hours 25 minutes earlier.

Area forecast discussion, Jul 24, 8:32 PM CDT, 4 hours 25 minutes before
SOUTH DAKOTA/NORTHWEST IOWA/SOUTHWEST MINNESOTA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
832 PM CDT THU JUL 24 1997

NEXRAD RADAR AT SIOUX FALLS SHOWS SMALL CLUSTERS OF THUNDERSTORMS DVLPG
JUST S OF LAKE ANDES...JUST N OF HURON AND AROUND THE SIOUX FALLS AREA.
NEXRAD RADAR AT SIOUX FALLS HAS SHOWN SEVERE SIGNATURES WITH SOME OF
THESE THUNDERSTORMS. FORECASTS ATTM LOOK REASONABLY GOOD SO UPDATES...
IF ANY...SHOULD BE FOR MINOR CHANGES ONLY. NO TSTMS VCNTY FLASH FLOOD
WATCH IN NORTHWEST IOWA ATTM BUT POTENTIAL STILL THERE FOR HEAVY RAIN
TOWARD MIDNIGHT AND AFTER.

.FSD...NONE

BLOOM

In the hours before

Special weather statement, Jul 25, 12:01 AM CDT, 56 minutes before
SDZ052-240600-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  SIOUX FALLS SD
1201 AM CDT FRI JUL 25 1997

...SEVERE THUNDERSTORM WATCH FOR PORTIONS OF CENTRAL SOUTH DAKOTA HAS
BEEN CANCELLED...

THE THREAT OF SEVERE WEATHER HAS DECREASED THEREFORE THE SEVERE
THUNDERSTORM WATCH WHICH WAS IN EFFECT FOR THE AREA HAS BEEN CANCELLED

 JCV

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 24, 11:50 PM CDTSevere Thunderstorm WarningFSDLincoln35 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1997Every severe thunderstorm warning in 1997

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.