Alert archive / South Dakota / Mesoscale Discussions in 2004
Mesoscale Discussion 656
The Storm Prediction Center issued this mesoscale discussion at May 11, 2004, 4:04 PM MDT for 4 counties in Nebraska; 14 counties in South Dakota. It was in force for 116 min.
The area
The outline as issued.
The facts
- Issued
- May 11, 2004, 4:04 PM MDT (22:04 UTC)
- Expired
- May 11, 2004, 6:00 PM MDT
- In force
- 116 min
- Issued by
- the Storm Prediction Center
Counties Cherry County, NE, Grant County, NE, Hooker County, NE, Keya Paha County, NE, Bennett County, SD, Brule County, SD, Buffalo County, SD, Faulk County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Jackson County, SD, Jones County, SD, Lyman County, SD, Mellette County, SD, Sully County, SD, Todd County, SD, Tripp County, SD
The radar
The North Platte radar (KLNX), 162 km from the middle of the area, began a volume at 22:08 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Rapid City, SD (KUNR), launched 12:00Z, 10.1 hours before the alert went out and 184 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
- 650 J/kg
- Mixed-layer CIN
- -270 J/kg
- Mixed-layer LCL
- 1233 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 73 m²/s²
- 0-3 km storm-relative helicity
- 356 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
541 ACUS11 KWNS 112204 SWOMCD SPC MCD 112204 SDZ000-NEZ000-120000- MESOSCALE DISCUSSION 0656 NWS STORM PREDICTION CENTER NORMAN OK 0504 PM CDT TUE MAY 11 2004 AREAS AFFECTED...CNTRL SD INTO W CNTRL NEB CONCERNING...SEVERE THUNDERSTORM WATCH 184... VALID 112204Z - 120000Z CONTINUE REMAINING VALID PORTION OF WW. DEVELOPMENT OF INTENSE THUNDERSTORMS IS ONGOING NEAR DEEP SURFACE LOW ...NORTHWEST OF PIERRE SD...SOUTHWARD ALONG DRY LINE INTO AREAS EAST OF ALLIANCE NEB...WHERE CONVECTIVE TEMPERATURES HAVE BEEN REACHED WITH STRONG HEATING. MEAN MIXED LAYER CAPE IN EXCESS OF 2000 J/KG WILL REMAIN SUPPORTIVE OF INTENSE UPDRAFTS WITH LARGE HAIL IN MODERATELY SHEARED ENVIRONMENT INTO THE EARLY EVENING HOURS. LARGE BOUNDARY LAYER TEMPERATURE/DEW POINT SPREADS WILL ALSO CONTRIBUTE TO POTENTIAL FOR A FEW DAMAGING DOWNBURSTS. RIGHT ENTRANCE REGION OF UPPER JET LIFTING OUT OF LARGE-SCALE TROUGH OVER THE INTERMOUNTAIN WEST MAY ENHANCE CONVECTION NEXT FEW HOURS. EVOLUTION OF LARGE MESOSCALE CONVECTIVE SYSTEM APPEARS LIKELY SOUTHEAST OF SURFACE LOW BY THE 12/00-02Z TIME FRAME...ACROSS PIERRE AND SURROUNDING AREAS. THIS SHOULD BE ACCOMPANIED BY SUBSTANTIAL SURFACE COLD POOL/MESO HIGH. INCREASE IN POTENTIAL FOR DAMAGING WINDS SHOULD MAINLY BE IN AREAS EAST/SOUTH OF PIERRE ...AS SHARP SURFACE COLD FRONT BEGINS TO SURGE SOUTHWARD INTO WESTERN/CENTRAL SOUTH DAKOTA. ..KERR.. 05/11/2004 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...FSD...ABR...LBF...UNR... 42140235 43020194 43830166 44510059 44820017 45089983 45099915 44079875 42579983 41740086 41860190
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 10, 7:06 PM MDT | Mesoscale Discussion | SPC | Banner, Box Butte, Cheyenne, Dawes, Deuel, Garden and 5 more | 114 min |
| May 10, 7:30 PM MDT | Severe Thunderstorm Watch | SPC | Banner, Kimball, Scotts Bluff | 5 hr |
| May 10, 9:19 PM MDT | Mesoscale Discussion | SPC | Banner, Scotts Bluff, Sioux | 116 min |
| May 10, 9:45 PM MDT | Severe Thunderstorm Watch | SPC | Arthur, Box Butte, Chase, Cheyenne, Custer, Dawes and 21 more | 4 hr |
| May 11, 12:27 AM MDT | Mesoscale Discussion | SPC | Arthur, Brown, Cherry, Grant, Hooker, Keya Paha and 3 more | 63 min |
| May 11, 12:32 PM MDT | Mesoscale Discussion | SPC | Cherry, Dawes, Sheridan | 118 min |
| May 11, 12:55 PM MDT | Severe Thunderstorm Watch | SPC | Arthur, Cherry, Garden, Grant, Hooker, Keith and 4 more | 5 hr |
| May 11, 1:00 PM MDT | Mesoscale Discussion | SPC | Chase, Dundy, Hayes, Hitchcock | 2 hr |
| May 11, 1:40 PM MDT | Tornado Watch | SPC | Chase, Dawson, Dundy, Frontier, Furnas, Gosper and 5 more | 6 hr |
| May 11, 4:20 PM MDT | Mesoscale Discussion | SPC | Frontier, Hayes, Hitchcock, Lincoln, Red Willow | 115 min |
| May 11, 5:40 PM MDT | Severe Thunderstorm Watch | SPC | Antelope, Blaine, Boyd, Brown, Holt, Keya Paha and 5 more | 6 hr |
| May 11, 2:55 PM MDT | Tornado Watch | SPC | Beadle, Brown, Clark, Codington, Day, Deuel and 10 more | 5 hr |
| May 11, 4:37 PM MDT | Mesoscale Discussion | SPC | Brown, Day, Edmunds, McPherson, Marshall, Roberts | 113 min |
| May 11, 5:53 PM MDT | Mesoscale Discussion | SPC | Aurora, Beadle, Brule, Buffalo, Charles Mix, Clark and 18 more | 2 hr |
Nearby
Mesoscale Discussions in South Dakota, 2004Mesoscale Discussions in Nebraska, 2004Every mesoscale discussion in 2004
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.