Alert archive / North Dakota / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 175, NWS Bismarck, ND

October 11, 1997Sioux County, North Dakota

NWS Bismarck, ND issued this severe thunderstorm warning at Oct 11, 1997, 6:48 PM CDT for Sioux County, North Dakota. It was in force for 57 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Oct 11, 1997, 6:48 PM CDT (23:48 UTC)
Expired
Oct 11, 1997, 7:45 PM CDT
In force
57 min
Issued by
NWS Bismarck, ND
Area
Whole counties

County Sioux County, ND

The radar

The Bismarck radar (KBIS), 76 km from the middle of the area, began a volume at 23:48 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.

The watch it was issued in

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

IssuedProductOfficeLasted
Oct 11, 4:15 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 11.8 hours before the alert went out and 78 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, Bismarck Municip, ND at 12:00Z on 1997-10-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1646 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, Bismarck Municip, ND at 12:00Z on 1997-10-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 517 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
1646 J/kg
Mixed-layer CIN
-225 J/kg
Mixed-layer LCL
916 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
517 m²/s²
0-3 km storm-relative helicity
473 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KBIS 112350 RRA
SVRBIS
NDC085-120045-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE BISMARCK ND
648 PM CDT (548 PM MDT) SAT OCT 11 1997
 
THE NATIONAL WEATHER SERVICE IN BISMARCK HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  745 PM CDT (645 PM MDT)
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTH CENTRAL NORTH DAKOTA
 
   ...SIOUX COUNTY
 
AT 545 PM MDT(645 PM CDT) A SEVERE THUNDERSTORM WAS LOCATED 61 MILES
SOUTHWEST OF BISMARCK OR 40 MILES WEST OF FORT YATES. THE STORM IS
MOVING NORTH AT 40 TO 45 MPH. PERSONS IN AND NEAR THE TOWN OF SELFRIDGE
CAN EXPECTED THIS STORM BETWEEN 615 AND 625 PM MDT.
 
THIS STORM HAS A HISTORY OF PRODUCING GOLFBALL SIZED HAIL IN SOUTH
DAKOTA.
 
A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNING AREA UNTIL 9 PM MDT.
 
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.  REMAIN CALM BUT BE ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS.
 
 
HINTZ

Nearby

Severe Thunderstorm Warnings in North Dakota, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.