Alert archive / South Dakota / Mesoscale Discussions in 2012
Mesoscale Discussion 1549
The Storm Prediction Center issued this mesoscale discussion at Jul 22, 2012, 10:58 PM CDT for 35 counties in South Dakota. It was in force for 107 min.
The area
The outline as issued.
The facts
- Issued
- Jul 22, 2012, 10:58 PM CDT (03:58 UTC)
- Expired
- Jul 23, 2012, 12:45 AM CDT
- In force
- 107 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
All 35 counties
Aurora County, SD, Beadle County, SD, Bennett County, SD, Bon Homme County, SD, Brookings County, SD, Brule County, SD, Buffalo County, SD, Charles Mix County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Haakon County, SD, Hand County, SD, Hanson County, SD, Hughes County, SD, Hutchinson County, SD, Hyde County, SD, Jackson County, SD, Jerauld County, SD, Jones County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, Lyman County, SD, McCook County, SD, Mellette County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Stanley County, SD, Todd County, SD, Tripp County, SD, Turner County, SD, Yankton County, SD
The radar
The Sioux Falls radar (KFSD), 183 km from the middle of the area, began a volume at 03:57 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, 4.0 hours before the alert went out and 155 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
- 2811 J/kg
- Mixed-layer CIN
- -87 J/kg
- Mixed-layer LCL
- 1819 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 42 m²/s²
- 0-3 km storm-relative helicity
- 87 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 4.8
The text
As transmitted, in the capitals the NWS used until 2016.
206
ACUS11 KWNS 230359
SWOMCD
SPC MCD 230358 COR
IAZ000-MNZ000-SDZ000-NEZ000-230545-
MESOSCALE DISCUSSION 1549
NWS STORM PREDICTION CENTER NORMAN OK
1058 PM CDT SUN JUL 22 2012
AREAS AFFECTED...SRN SD
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 230358Z - 230545Z
CORRECTED FOR GRAPHIC
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...ADDITIONAL TSTM DEVELOPMENT IS EXPECTED THROUGH 08Z. THE
STRONGEST TSTMS MAY PRODUCE SVR HAIL AND GUSTY WINDS. A WW IS NOT
EXPECTED DUE TO THE ISOLATED NATURE OF THE SVR THREAT...HOWEVER
CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED.
DISCUSSION...A FEW TSTMS HAVE DEVELOPED OVER SRN SD SINCE 0130Z
NORTH OF A NEARLY STNRY SFC BOUNDARY OVER NRN NEB. LATEST VWP FROM
KLNX SHOWS A 30 KT LOW-LVL JET HAS BECOME ESTABLISHED ACROSS CENTRAL
NEB AND THIS IS FCST TO INCREASE TO 40-45KT BY 06Z. IN
RESPONSE...INCREASING ISENTROPIC LIFT IS EXPECTED ACROSS SRN SD
THROUGH 08Z-10Z TIME FRAME. THEREAFTER...THE LOW-LEVEL JET IS FCST
TO VEER WITH A RESULTANT WEAKENING OF THE WAA. WITH MUCAPE VALUES OF
1500-2500 J/KG...LOCALLY HIGHER ACROSS SERN SD...AND EFFECTIVE BULK
SHEAR VALUES OF 30-35 KT...ISOLD/WIDELY SCTD STG/SVR TSTMS WITH A
THREAT OF LARGE HAIL AND GUSTY WINDS SHOULD CONTINUE INTO THE EARLY
MORNING HOURS.
..BUNTING/CARBIN.. 07/23/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FSD...ABR...LBF...UNR...
LAT...LON 42969695 42949884 42970099 42970159 43580232 44120198
44670085 44649804 44399664 43619629 43079660 42969695SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 22, 8:13 PM CDT | Mesoscale Discussion | SPC | Brown, Campbell, Codington, Corson, Day, Dewey and 9 more | 62 min |
| Jul 23, 6:31 PM CDT | Mesoscale Discussion | SPC | Butte, Custer, Dewey, Haakon, Harding, Hughes and 12 more | 89 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.