Alert archive / South Dakota / Mesoscale Discussions in 2012
Mesoscale Discussion 1282
The Storm Prediction Center issued this mesoscale discussion at Jun 25, 2012, 7:37 PM MDT for 17 counties in South Dakota. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Jun 25, 2012, 7:37 PM MDT (01:37 UTC)
- Expired
- Jun 25, 2012, 9:00 PM MDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
Counties Bennett County, SD, Corson County, SD, Dewey County, SD, Haakon County, SD, Hughes County, SD, Jackson County, SD, Jones County, SD, Lyman County, SD, Meade County, SD, Mellette County, SD, Perkins County, SD, Potter County, SD, Stanley County, SD, Sully County, SD, Todd County, SD, Walworth County, SD, Ziebach County, SD
The radar
The Rapid City radar (KUDX), 138 km from the middle of the area, began a volume at 01:39 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
Rapid City, SD (KUNR), launched 00:00Z, 1.6 hours before the alert went out and 145 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
- 2797 J/kg
- Mixed-layer CIN
- -194 J/kg
- Mixed-layer LCL
- 1624 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 107 m²/s²
- 0-3 km storm-relative helicity
- 140 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 4.5
The text
As transmitted, in the capitals the NWS used until 2016.
181
ACUS11 KWNS 260138
SWOMCD
SPC MCD 260137
SDZ000-260300-
MESOSCALE DISCUSSION 1282
NWS STORM PREDICTION CENTER NORMAN OK
0837 PM CDT MON JUN 25 2012
AREAS AFFECTED...WRN THROUGH CNTRL SD
CONCERNING...SEVERE THUNDERSTORM WATCH 428...
VALID 260137Z - 260300Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 428
CONTINUES.
SUMMARY...GREATEST SEVERE WEATHER THREAT ACROSS REMAINING PART OF WW
428 WILL EXIST OVER WRN SD THROUGH 03Z. THREAT MAY SHIFT EWD INTO A
SMALL PART OF CNTRL SD...AND DEPENDING ON CONVECTIVE TRENDS DURING
THE NEXT 30 MIN...A SMALL WW MIGHT BE NEEDED.
DISCUSSION...STORMS HAVE EVOLVED INTO A SMALL MCS OVER WRN SD WHERE
NEW STORMS CONTINUE DEVELOPING ALONG CONSOLIDATED CONVECTIVE OUTFLOW
BOUNDARY. ACTIVITY IS MOVING EAST AT AROUND 35 KT. DESPITE THE
RATHER STRONG CAP INDICATED ON THE 00Z RAPID CITY RAOB...MESOSCALE
LIFT ALONG THE OUTFLOW BOUNDARY HAS HELPED TO SUSTAIN ACTIVITY SO
FAR. LATEST OBJECTIVE ANALYSIS SHOW THE INSTABILITY AXIS EXTENDS
INTO CNTRL SD AS FAR AS PIERRE BEFORE DECREASING FARTHER EAST.
HOWEVER...THE CAP WILL CONTINUE TO STRENGTHEN AS THE BOUNDARY LAYER
BEGINS TO COOL...AND THIS RAISES UNCERTAINTY REGARDING LONGEVITY OF
A MORE ROBUST SEVERE THREAT...ESPECIALLY GIVEN THE MODEST SHEAR
PROFILES. IF STORMS CAN MAINTAIN THEIR INTENSITY AS THEY APPROACH
THE STANLEY AND JONES COUNTY BORDERS...A NEW BUT RELATIVELY SMALL WW
MIGHT BE WARRANTED.
..DIAL.. 06/26/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...ABR...UNR...
LAT...LON 45830241 45730006 44789957 43229997 43180191 45150338
45830241SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 25, 10:38 PM MDT | Mesoscale Discussion | SPC | Beadle, Brown, Clark, Edmunds, Faulk, Hand and 4 more | 67 min |
| Jun 26, 2:06 PM MDT | Mesoscale Discussion | SPC | Butte, Corson, Harding, Meade, Pennington, Perkins and 1 more | 54 min |
Nearby
Mesoscale Discussions in South Dakota, 2012Every mesoscale discussion in 2012
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.