Alert archive / South Dakota / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 83, NWS Aberdeen, SD
NWS Aberdeen, SD issued this severe thunderstorm warning at Jul 7, 1999, 9:08 PM MDT for Corson County, South Dakota. It was in force for 32 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
- Jul 7, 1999, 9:08 PM MDT (03:08 UTC)
- Expired
- Jul 7, 1999, 9:40 PM MDT
- In force
- 32 min
- Issued by
- NWS Aberdeen, SD
- Area
- Whole counties
County Corson County, SD
The radar
The Bismarck radar (KBIS), 123 km from the middle of the area, began a volume at 02:58 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 nearest sounding before it
Aberdeen, SD (KABR), launched 00:00Z, 3.1 hours before the alert went out and 237 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.
- Mixed-layer CAPE
- 22 J/kg
- Mixed-layer CIN
- -361 J/kg
- Mixed-layer LCL
- 2040 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- -4 m²/s²
- 0-3 km storm-relative helicity
- 137 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
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 Jul 7, 8:01 PM MDT, 1 hour 7 minutes earlier.
Area forecast discussion, Jul 7, 8:01 PM MDT, 1 hour 7 minutes before
AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 900 PM CDT WED JULY 7 1999 CURRENTLY WATCHING CONVECTION IN WESTERN SOUTH DAKOTA. CURRENT CAPE VALUES OF OVER 4K J/KG WITH -8 LIS IN PIR AREA PER LAPS MODEL. 00Z ABR SOUNDING SHOWS WARM MID LEVEL WITH H7 TEMP OF +11 C. CURRENT GOES SOUNDINGS ALSO SHOW WARM MID LEVELS WITH SIMILAR H7 TEMPS. ETA SHOWS STRONG WAA ESPECIALLY AT MID LEVEL WHICH SHOULD INHBIT CONVECTION TRYING TO MOVE INTO OUR CWA. CURRENT PACKAGE DESCRIBES SITUATION WELL AND NO CHANGES ARE ANTICIPATED. .ABR...NONE. KEEFE
The office that day
Everything else NWS Aberdeen, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 9:19 PM MDT | Severe Thunderstorm Warning | ABR | Campbell | 36 min |
| Jul 7, 10:19 PM MDT | Severe Thunderstorm Warning | ABR | Campbell, McPherson | 31 min |
| Jul 7, 10:50 PM MDT | Tornado Warning | ABR | McPherson | 35 min |
| Jul 7, 11:20 PM MDT | Tornado Warning | ABR | Edmunds | 30 min |
| Jul 7, 11:22 PM MDT | Tornado Warning | ABR | Brown | 48 min |
| Jul 7, 11:24 PM MDT | Tornado Warning | ABR | McPherson | 36 min |
| Jul 8, 12:28 AM MDT | Flash Flood Warning | ABR | McPherson | 4 hr |
| Jul 8, 12:46 AM MDT | Severe Thunderstorm Warning | ABR | Brown | 64 min |
| Jul 8, 1:43 AM MDT | Severe Thunderstorm Warning | ABR | Day | 62 min |
Nearby
Severe Thunderstorm Warnings in South Dakota, 1999Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.