Alert archive / Nebraska / Mesoscale Discussions in 2012
Mesoscale Discussion 1586
The Storm Prediction Center issued this mesoscale discussion at Jul 25, 2012, 2:52 PM CDT for 15 counties in Kansas; 48 counties in Nebraska; 6 counties in South Dakota. It was in force for 113 min.
The area
The outline as issued.
The facts
- Issued
- Jul 25, 2012, 2:52 PM CDT (19:52 UTC)
- Expired
- Jul 25, 2012, 4:45 PM CDT
- In force
- 113 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 69 counties
Decatur County, KS, Gove County, KS, Graham County, KS, Jewell County, KS, Logan County, KS, Norton County, KS, Osborne County, KS, Phillips County, KS, Rawlins County, KS, Republic County, KS, Rooks County, KS, Sheridan County, KS, Smith County, KS, Thomas County, KS, Trego County, KS, Adams County, NE, Antelope County, NE, Boone County, NE, Buffalo County, NE, Butler County, NE, Cedar County, NE, Clay County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dawson County, NE, Dixon County, NE, Dodge County, NE, Fillmore County, NE, Franklin County, NE, Frontier County, NE, Furnas County, NE, Garfield County, NE, Gosper County, NE, Greeley County, NE, Hall County, NE, Hamilton County, NE, Harlan County, NE, Hitchcock County, NE, Howard County, NE, Kearney County, NE, Knox County, NE, Madison County, NE, Merrick County, NE, Nance County, NE, Nuckolls County, NE, Phelps County, NE, Pierce County, NE, Platte County, NE, Polk County, NE, Red Willow County, NE, Saline County, NE, Saunders County, NE, Seward County, NE, Sherman County, NE, Stanton County, NE, Thayer County, NE, Thurston County, NE, Valley County, NE, Wayne County, NE, Webster County, NE, Wheeler County, NE, York County, NE, Bon Homme County, SD, Clay County, SD, Hutchinson County, SD, Turner County, SD, Union County, SD, Yankton County, SD
The radar
The Grand Island radar (KUEX), 96 km from the middle of the area, began a volume at 19:51 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
N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 7.9 hours before the alert went out and 166 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
- 646 J/kg
- Mixed-layer CIN
- -317 J/kg
- Mixed-layer LCL
- 1537 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- -72 m²/s²
- 0-3 km storm-relative helicity
- 58 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.2
The text
As transmitted, in the capitals the NWS used until 2016.
888
ACUS11 KWNS 251952
SWOMCD
SPC MCD 251952
IAZ000-NEZ000-SDZ000-KSZ000-252145-
MESOSCALE DISCUSSION 1586
NWS STORM PREDICTION CENTER NORMAN OK
0252 PM CDT WED JUL 25 2012
AREAS AFFECTED...NWRN/N-CNTRL KS...SWRN/S-CNTRL INTO NERN NEB...SERN
SD
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 251952Z - 252145Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...THE AREA IS BEING MONITORED FOR AN INCREASING SVR TSTM
POTENTIAL...AND THE ISSUANCE OF A SVR TSTM WATCH IS POSSIBLE ACROSS
PARTS OF THE AREA.
DISCUSSION...A SLOW-MOVING COLD FRONT EXTENDING FROM NERN NEB TO
W-CNTRL KS MARKS THE CONTRAST BETWEEN A DEEPLY/WELL-MIXED BOUNDARY
LAYER FEATURING HOT SFC TEMPS IN THE MID/UPPER 90S TO 102 DEGREES TO
ITS SE...FROM SLIGHTLY COOLER/MORE MOIST CONDITIONS TO ITS NW.
HOWEVER...AROUND THE MOIST AXIS CHARACTERIZED BY MIDDLE/UPPER 60S
DEWPOINTS NW OF THE COLD FRONT -- AND SOUTHEAST OF A DIFFERENTIAL
HEATING ZONE LYING PARALLEL TO...AND 60-75 MILES NW OF...THE COLD
FRONT -- CLOUD-FREE AREAS ARE CONTRIBUTING TO MLCAPE UP TO 2000 J/KG
PER MODIFIED NORTH PLATTE/OMAHA 12Z RAOBS. VISIBLE SATELLITE IMAGES
DEPICT ARCS/ZONES OF CUMULUS DEVELOPMENT WITHIN THIS ZONE...WITH
HIGHER-BASED CUMULUS DEVELOPMENT CLOSER TO THE COLD FRONT. ISOLATED
TO SCATTERED THUNDERSTORMS ARE EXPECTED TO EVOLVE FROM THIS CUMULUS
DURING THE NEXT COUPLE OF HOURS. AND...WITH 20-30 KT OF EFFECTIVE
BULK SHEAR -- HIGHEST NEAR THE DIFFERENTIAL HEATING ZONE --
MULTICELL CLUSTERS WITH DMGG WIND GUSTS AND PERHAPS SVR HAIL WILL BE
OF CONCERN. THESE FACTORS MAY WARRANT SVR TSTM WATCH ISSUANCE ACROSS
PARTS OF THE AREA...ESPECIALLY NEAR AND TO THE NORTHEAST OF THE
KS/NEB BORDER WHERE THE DIFFERENTIAL HEATING ZONE IS MORE
PRONOUNCED.
..COHEN/HART.. 07/25/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FSD...OAX...TOP...ICT...GID...LBF...DDC...GLD...
LAT...LON 43249669 42519651 41209639 40159717 39209858 38660007
38700095 39030154 39760152 40630076 41489936 42849822
43429771 43519710 43249669SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 25, 4:28 PM CDT | Severe Thunderstorm Watch | SPC | Clay, Cloud, Jewell, Marshall, Mitchell, Nemaha and 7 more | 7 hr |
| Jul 25, 4:48 PM CDT | Mesoscale Discussion | SPC | Allen, Anderson, Barber, Barton, Butler, Chase and 29 more | 117 min |
| Jul 24, 8:01 PM CDT | Severe Thunderstorm Watch | SPC | Campbell, Corson, Dewey, Edmunds, Faulk, Harding and 10 more | 7 hr |
| Jul 24, 11:24 PM CDT | Mesoscale Discussion | SPC | Brown, Campbell, Clark, Codington, Day, Edmunds and 8 more | 96 min |
| Jul 25, 5:24 AM CDT | Mesoscale Discussion | SPC | Day, Marshall, Roberts | 66 min |
| Jul 25, 1:56 PM CDT | Mesoscale Discussion | SPC | Brown, Clark, Codington, Day, Edmunds, Faulk and 5 more | 2 hr |
Nearby
Mesoscale Discussions in Nebraska, 2012Mesoscale Discussions in Kansas, 2012Mesoscale 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.