Alert archive / South Dakota / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 103, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jul 23, 1987, 12:20 PM CDT for Todd County, South Dakota. It was in force for 55 min.
The area
The counties it named.
The facts
- Issued
- Jul 23, 1987, 12:20 PM CDT (17:20 UTC)
- Expired
- Jul 23, 1987, 1:15 PM CDT
- In force
- 55 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Todd County, SD
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
The nearest sounding before it
Rapid City, SD (KRAP), launched 12:00Z, 5.3 hours before the alert went out and 199 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
- 1084 J/kg
- Mixed-layer CIN
- -249 J/kg
- Mixed-layer LCL
- 1075 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km storm-relative helicity
- 94 m²/s²
- 0-3 km storm-relative helicity
- 200 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.9
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.
In the hours before
Special weather statement, Jul 23, 6:36 AM CDT, 5 hours 44 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 635 AM CDT THU JUL 23 1987 AT 630 AM CDT...ISOLATED INTENSE THUNDERSTORMS HAD DEVELOPED OVER EXTREME NORTHEAST SOUTH DAKOTA...50 MILES NORTHEAST OF ABERDEEN AND 70 MILES NORTH OF WATERTOWN. VERY HEAVY RAIN AND STRONG WIND IS LIKELY WITH THESE STORMS. SMALL HAIL IS POSSIBLE. THE STORMS WOULD MOVE OUT OF SOUTH DAKOTA BY 730 AM CDT. NUMEROUS SHOWERS AND THUNDERSTORMS...SOME WITH HEAVY RAIN... CONTINUED OVER NORTHEAST SOUTH DAKOTA...IN THE AREA EAST OF THE MISSOURI RIVER AND NORTH OF A LINE FROM MOBRIDGE TO WEBSTER... WHICH IS 35 MILES NORTHWEST OF WATERTOWN. MOVEMENT WAS EAST AT 40 MILES AN HOUR. SPRINGER
Special weather statement, Jul 23, 7:36 AM CDT, 4 hours 44 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY NATIONAL WEATHER SERVICE HURON SD 735 AM CDT THU JUL 23 1987 AT 730 AM CDT...SCATTERED INTENSE THUNDERSTORMS WERE OCCURRING OVER NORTHEAST SOUTH DAKONTA...MAINLY IN THE AREA EAST OF THE JAMES RIVER AND NORTH OF A LINE FROM ABERDEEN TO WATERTOWN. VERY HEAVY RAIN AND STRONG WIND IS LIKELY WITH THESE STORMS. SMALL HAIL IS POSSIBLE. MOVEMENT WAS EAST AT 40 MILES AN HOUR. SPRINGER
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 23, 12:31 PM CDT | Severe Thunderstorm Warning | FSD | Gregory | 59 min |
| Jul 23, 1:02 PM CDT | Severe Thunderstorm Warning | FSD | Charles Mix | 43 min |
| Jul 23, 1:44 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Yankton | 46 min |
| Jul 23, 1:54 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Charles Mix | 66 min |
| Jul 23, 6:39 PM CDT | Severe Thunderstorm Warning | FSD | Todd | 66 min |
Nearby
Severe Thunderstorm Warnings in South Dakota, 1987Every severe thunderstorm warning in 1987
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.