Alert archive / Oklahoma / Mesoscale Discussions in 2012
Mesoscale Discussion 642
The Storm Prediction Center issued this mesoscale discussion at May 1, 2012, 1:19 AM CDT for 4 states. It was in force for 56 min.
The area
The outline as issued.
The facts
- Issued
- May 1, 2012, 1:19 AM CDT (06:19 UTC)
- Expired
- May 1, 2012, 2:15 AM CDT
- In force
- 56 min
- Issued by
- the Storm Prediction Center
All 40 counties
Benton County, AR, Carroll County, AR, Washington County, AR, Cherokee County, KS, Labette County, KS, Montgomery County, KS, Barry County, MO, Jasper County, MO, Lawrence County, MO, McDonald County, MO, Newton County, MO, Adair County, OK, Carter County, OK, Cherokee County, OK, Cleveland County, OK, Craig County, OK, Creek County, OK, Delaware County, OK, Garvin County, OK, Hughes County, OK, Jefferson County, OK, Johnston County, OK, Lincoln County, OK, Mayes County, OK, McClain County, OK, McIntosh County, OK, Murray County, OK, Muskogee County, OK, Nowata County, OK, Okfuskee County, OK, Okmulgee County, OK, Ottawa County, OK, Pontotoc County, OK, Pottawatomie County, OK, Rogers County, OK, Seminole County, OK, Stephens County, OK, Tulsa County, OK, Wagoner County, OK, Washington County, OK
The radar
The Tulsa radar (KINX), 53 km from the middle of the area, began a volume at 06:20 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
Norman, OK (KOUN), launched 00:00Z, 6.3 hours before the alert went out and 161 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
- 2178 J/kg
- Mixed-layer CIN
- -5 J/kg
- Mixed-layer LCL
- 1251 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 47 m²/s²
- 0-3 km storm-relative helicity
- 174 m²/s²
- Significant tornado parameter
- 1.2
- Supercell composite
- 10.1
The text
As transmitted, in the capitals the NWS used until 2016.
451
ACUS11 KWNS 010619
SWOMCD
SPC MCD 010619
MOZ000-ARZ000-OKZ000-KSZ000-TXZ000-010715-
MESOSCALE DISCUSSION 0642
NWS STORM PREDICTION CENTER NORMAN OK
0119 AM CDT TUE MAY 01 2012
AREAS AFFECTED...CENTRAL AND ERN OK/SERN KS/SWRN MO/NWRN AR
CONCERNING...TORNADO WATCH 214...215...
VALID 010619Z - 010715Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 214...215...CONTINUES.
TORNADO POTENTIAL HAS DECREASED OVER THE PAST 1-2 HOURS...WITH
STORMS NOW ORGANIZED IN A MUCH MORE LINEAR FASHION. ATTM...A
COMPLEX LINE OF STORMS EXTENDS FROM SWRN MO/NERN OK/SERN KS SWWD
INTO S CENTRAL OK...WITH THE STRONGEST STORMS NOW OVER NERN OK WHERE
A FAST-MOVING BOW ECHO CONTINUES MOVING EWD TOWARD SWRN MO/NWRN AR.
AT ITS CURRENT EWD SPEED OF AROUND 50 KT...THIS BOW WILL BE EXITING
THE STRONGER INSTABILITY AXIS IN THE NEXT 1-2 HOURS. THUS...IT
REMAINS UNCERTAIN WHETHER A NEW/DOWNSTREAM WW WILL BE REQUIRED AFTER
THE 01/07Z EXPIRATION OF WW 214/215.
..GOSS.. 05/01/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...SGF...TSA...ICT...FWD...OUN...
LAT...LON 37469363 36409350 35719393 35569532 34939608 34029678
33899813 34459824 35589719 36059641 37169602 37469363SPC 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 | Benton, Washington | 7 hr |
| May 1, 1:43 AM CDT | Severe Thunderstorm Watch | SPC | Benton, Carroll, Madison, Washington | 3 hr |
| Apr 30, 8:55 PM CDT | Mesoscale Discussion | SPC | Allen, Barber, Bourbon, Butler, Chautauqua, Cherokee and 17 more | 65 min |
| Apr 30, 11:28 PM CDT | Mesoscale Discussion | SPC | Allen, Bourbon, Chautauqua, Cherokee, Cowley, Crawford and 7 more | 92 min |
| Apr 30, 9:51 PM CDT | Tornado Watch | SPC | Caddo, Canadian, Carter, Cleveland, Comanche, Cotton and 19 more | 4 hr |
Nearby
Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Missouri, 2012Mesoscale Discussions in Arkansas, 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.