Alert archive / South Dakota / Severe Thunderstorm Watches in 1997

Severe Thunderstorm Watch 477

June 18, 19979 counties in South Dakota; 5 counties in Wyoming

The Storm Prediction Center issued this severe thunderstorm watch at Jun 18, 1997, 6:45 PM MDT for 9 counties in South Dakota; 5 counties in Wyoming. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jun 18, 1997, 6:45 PM MDT (00:45 UTC)
Expired
Jun 19, 1997, 12:00 AM MDT
In force
5 hr
Issued by
the Storm Prediction Center

Counties Butte County, SD, Custer County, SD, Fall River County, SD, Harding County, SD, Lawrence County, SD, Meade County, SD, Oglala Lakota County, SD, Pennington County, SD, Perkins County, SD, Campbell County, WY, Converse County, WY, Crook County, WY, Niobrara County, WY, Weston County, WY

The radar

The Rapid City radar (KUDX), 107 km from the middle of the area, began a volume at 00:44 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.

Warnings issued inside it

7 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 18, 8:54 PM MDTSevere Thunderstorm WarningUNRHarding31 min
Jun 18, 9:18 PM MDTSevere Thunderstorm WarningUNRButte42 min
Jun 18, 9:23 PM MDTSevere Thunderstorm WarningUNRHarding32 min
Jun 18, 9:43 PM MDTSevere Thunderstorm WarningUNRPerkins62 min
Jun 18, 10:00 PM MDTSevere Thunderstorm WarningUNRButte30 min
Jun 18, 10:30 PM MDTSevere Thunderstorm WarningUNRPerkins60 min
Jun 18, 10:45 PM MDTSevere Thunderstorm WarningUNRPerkins45 min

The nearest sounding before it

Riverton, WY (KRIW), launched 00:00Z, 0.8 hours before the alert went out and 371 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, Riverton, WY at 00:00Z on 1997-06-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 00:00Z on 1997-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
5 J/kg
Mixed-layer CIN
-135 J/kg
Mixed-layer LCL
2222 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
123 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 19, 2:15 PM MDTTornado WatchSPCBennett, Fall River, Oglala Lakota7 hr
Jun 19, 5:30 PM MDTTornado WatchSPCBon Homme, Clay, Gregory, Todd, Union, Yankton6 hr

Nearby

Severe Thunderstorm Watches in South Dakota, 1997Severe Thunderstorm Watches in Wyoming, 1997Every severe thunderstorm watch 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.