Alert archive / Minnesota / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 117, NWS Grand Forks, ND

July 13, 1997Norman County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 13, 1997, 4:10 PM CDT for Norman County, Minnesota. It was in force for 35 min. 3 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 13, 1997, 4:10 PM CDT (21:10 UTC)
Expired
Jul 13, 1997, 4:45 PM CDT
In force
35 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

County Norman County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 69 km from the middle of the area, began a volume at 21:11 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 13, 4:15 PM CDTThunderstorm WindAda, MNSeveral large trees were uprooted due to the strong wind.
Jul 13, 4:15 PM CDTThunderstorm WindTwin Vly, MNLarge trees were blown over due to the strong wind.
Jul 13, 4:18 PM CDTHail 0.75Twin Vly, 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 nearest sounding before it

International Fa, MN (KINL), launched 12:00Z, 9.2 hours before the alert went out and 273 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, International Fa, MN at 12:00Z on 1997-07-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 303 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, International Fa, MN at 12:00Z on 1997-07-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 square meters per square second.193958Sfc1 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
303 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
617 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
23 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 KFAR 132111 RRA
SVRFAR
MNC107-132145-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
410 PM CDT SUN JUL 13 1997
 
THE NATIONAL WEATHER SERVICE IN EASTERN ND/GRAND FORKS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  445 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN WEST CENTRAL MINNESOTA
 
   ...NORMAN COUNTY
 
AT 408 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM WAS LOCATED AT TWIN
VALLEY MINNESOTA OR 35 MILES NORTHEAST OF FARGO. MOVEMENT WAS NORTHEAST
AT 20 MPH. THE THUNDERSTORMS WILL REACH WAUKON MINNESOTA AROUND 440 PM
CDT. ONE INCH HAIL WAS REPORTED BY LAW ENFORCEMENT IN TWIN VALLEY.
 
REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO
PRODUCE TORNADOES WITH LITTLE OR NO ADVANCE WARNING.
 
HOPPES
&

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 Grand Forks, ND wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 13, 3:00 PM CDT, 1 hour 10 minutes earlier.

Area forecast discussion, Jul 13, 3:00 PM CDT, 1 hour 10 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
300 PM CDT SUN JUL 13 1997

FIRST PERIOD DISCUSSION...88D SHOWING HEALTHY STRMS FM NEAR
MAYVILLE TO WAHPETON ND. MVMNT NE AT 25 MPH. GRIDDED DATA
HAS JET STREAK INTO CNTRL ND FCST TO SHFT E INTO ERN ND BY
00Z. APPARENTLY CU FIELD SUPPRESSED W OF TSRA LINE INTO CNTRL
ND. ATMOS QUITE UNSTABLE WL LIKELY NEED HI VILS TO GET HAIL.
WATER VAPOR IMAGERY SHOWING SOME DRIER MID LVL AIR TRYING TO
MOV INTO ERN ND...MAY GIVE STRMS MORE POTENTIAL FOR PRODUCING
STRNG WNDS. WATER VAPOR ALSO SHOWS VORT MAX ALNG WRN BD BRDR AND
PSBLY ANOTHER VORT MAX IN CNTRL SD. MOS TEMPS REASONABLE FOR
OVRNT LOWS...SHUD SEE MID 60S MOST PLACES.

HOPPES

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 13, 4:26 PM CDTSevere Thunderstorm WarningFGFMahnomen34 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; radar from the NEXRAD Level II archive.