Alert archive / South Dakota / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 145, NWS Aberdeen, SD

August 12, 1999Campbell County, South Dakota

NWS Aberdeen, SD issued this severe thunderstorm warning at Aug 12, 1999, 2:05 AM CDT for Campbell County, South Dakota. It was in force for 65 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: Aug 12, 1999, 2:05 AM CDT (07:05 UTC)
Expired: Aug 12, 1999, 3:10 AM CDT
In force: 65 min
Issued by: NWS Aberdeen, SD
Area: Whole counties

County Campbell County, SD

The radar

The Bismarck radar (KBIS), 124 km from the middle of the area, began a volume at 07:09 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

Time	Report	Where	Remark
Aug 12, 2:20 AM CDT	Thunderstorm Wind 52	Mound City, SD

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.

Issued	Product	Office	Lasted
Aug 11, 10:45 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 7.1 hours before the alert went out and 122 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1951 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 806 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 265 m²/s²
Significant tornado parameter: 1.7
Supercell composite: 13.0

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.

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 Aberdeen, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 11, 9:00 PM CDT, 5 hours 5 minutes earlier.

Area forecast discussion, Aug 11, 9:00 PM CDT, 5 hours 5 minutes before

AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA
NATIONAL WEATHER SERVICE ABERDEEN SD
9 PM CDT WED AUG 11 1999

CURRENT RADAR AND SATELITTE SHOWING VERY LITTLE CONVECTIVE ACTIVITY
IN ABERDEEN COUNTY WARNING AREA.  MSAS HAS LOW CENTER IN WEST
CENTRAL SOUTH DAKOTA WITH WARM FRONT ALONG NORTH AND SOUTH DAKOTA
BORDER.  POTENTIAL IS STRONG ENOUGH TO STAY WITH CURRENT FORECAST AS
LOW LEVEL JET STRENGTHENS.  WILL UPDATE CURRENT PACKAGE FOR MINOR
WORDING.

.ABR...NONE.

KEEFE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 10:44 PM CDT	Severe Thunderstorm Warning	ABR	Corson	61 min
Aug 11, 11:44 PM CDT	Severe Thunderstorm Warning	ABR	Corson	61 min
Aug 12, 12:11 AM CDT	Severe Thunderstorm Warning	ABR	Dewey	64 min
Aug 12, 12:44 AM CDT	Severe Thunderstorm Warning	ABR	Corson	61 min
Aug 12, 1:11 AM CDT	Severe Thunderstorm Warning	ABR	Dewey	64 min
Aug 12, 1:27 AM CDT	Tornado Warning	ABR	Dewey	33 min
Aug 12, 1:44 AM CDT	Severe Thunderstorm Warning	ABR	Corson	61 min
Aug 12, 1:47 AM CDT	Severe Thunderstorm Warning	ABR	Walworth	63 min
Aug 12, 5:03 AM CDT	Severe Thunderstorm Warning	ABR	Brown, Spink	47 min
Aug 12, 5:26 AM CDT	Tornado Warning	ABR	Brown, Spink	49 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 1999 Every severe thunderstorm warning in 1999

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.