Alert archive / Oklahoma / Mesoscale Discussions in 2012
Mesoscale Discussion 639
The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2012, 8:55 PM CDT for 4 states. It was in force for 65 min.
The area
The outline as issued.
The facts
- Issued
- Apr 30, 2012, 8:55 PM CDT (01:55 UTC)
- Expired
- Apr 30, 2012, 10:00 PM CDT
- In force
- 65 min
- Issued by
- the Storm Prediction Center
All 81 counties
Allen County, KS, Barber County, KS, Bourbon County, KS, Butler County, KS, Chautauqua County, KS, Cherokee County, KS, Comanche County, KS, Cowley County, KS, Crawford County, KS, Edwards County, KS, Elk County, KS, Greenwood County, KS, Harper County, KS, Kingman County, KS, Kiowa County, KS, Labette County, KS, Montgomery County, KS, Neosho County, KS, Pratt County, KS, Sedgwick County, KS, Sumner County, KS, Wilson County, KS, Woodson County, KS, Barton County, MO, Jasper County, MO, Alfalfa County, OK, Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Cleveland County, OK, Comanche County, OK, Craig County, OK, Creek County, OK, Custer County, OK, Delaware County, OK, Dewey County, OK, Ellis County, OK, Garfield County, OK, Garvin County, OK, Grady County, OK, Grant County, OK, Greer County, OK, Harmon County, OK, Harper County, OK, Hughes County, OK, Jackson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, Major County, OK, Mayes County, OK, McClain County, OK, Murray County, OK, Noble County, OK, Nowata County, OK, Okfuskee County, OK, Oklahoma County, OK, Okmulgee County, OK, Osage County, OK, Ottawa County, OK, Pawnee County, OK, Payne County, OK, Pontotoc County, OK, Pottawatomie County, OK, Roger Mills County, OK, Rogers County, OK, Seminole County, OK, Stephens County, OK, Tulsa County, OK, Wagoner County, OK, Washington County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Collingsworth County, TX, Donley County, TX, Hemphill County, TX, Wheeler County, TX
The radar
The Norman radar (KTLX), 91 km from the middle of the area, began a volume at 01:57 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Lamont, OK (KLMN), launched 00:00Z, 1.9 hours before the alert went out and 88 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
- 2077 J/kg
- Mixed-layer CIN
- -10 J/kg
- Mixed-layer LCL
- 1205 m above ground
- 0-6 km bulk shear
- 50 kt
- 0-1 km storm-relative helicity
- 86 m²/s²
- 0-3 km storm-relative helicity
- 246 m²/s²
- Significant tornado parameter
- 2.4
- Supercell composite
- 16.5
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 30, 7:30 PM CDT | Tornado Watch | SPC | Allen, Barton, Bourbon, Butler, Chase, Chautauqua and 19 more | 7 hr |
| Apr 30, 11:28 PM CDT | Mesoscale Discussion | SPC | Allen, Bourbon, Chautauqua, Cherokee, Cowley, Crawford and 7 more | 92 min |
| May 1, 1:19 AM CDT | Mesoscale Discussion | SPC | Cherokee, Labette, Montgomery | 56 min |
| May 1, 1:43 AM CDT | Severe Thunderstorm Watch | SPC | Barry, Christian, Greene, Jasper, Lawrence, McDonald and 3 more | 3 hr |
| Apr 30, 9:51 PM CDT | Tornado Watch | SPC | Caddo, Canadian, Carter, Cleveland, Comanche, Cotton and 19 more | 4 hr |
| Apr 30, 9:37 PM CDT | Mesoscale Discussion | SPC | Bandera, Baylor, Brown, Callahan, Coke, Coleman and 33 more | 113 min |
| May 1, 5:43 PM CDT | Mesoscale Discussion | SPC | Brewster, Crane, Crockett, Edwards, Kinney, Maverick and 5 more | 3 hr |
Nearby
Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Kansas, 2012Mesoscale Discussions in Texas, 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.