Alert archive / Oklahoma / Mesoscale Discussions in 2012
Mesoscale Discussion 512
The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2012, 5:47 PM CDT for 31 counties in Oklahoma; Hardeman County, Texas. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- Apr 13, 2012, 5:47 PM CDT (22:47 UTC)
- Expired
- Apr 13, 2012, 7:15 PM CDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
All 32 counties
Blaine County, OK, Caddo County, OK, Canadian County, OK, Cleveland County, OK, Comanche County, OK, Creek County, OK, Custer County, OK, Garfield County, OK, Grady County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, McClain County, OK, Noble County, OK, Okfuskee County, OK, Oklahoma County, OK, Okmulgee County, OK, Osage County, OK, Pawnee County, OK, Payne County, OK, Pottawatomie County, OK, Rogers County, OK, Tillman County, OK, Tulsa County, OK, Wagoner County, OK, Washita County, OK, Hardeman County, TX
The radar
The Norman radar (KTLX), 75 km from the middle of the area, began a volume at 22:47 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 12:00Z, 10.8 hours before the alert went out and 62 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
- 1194 J/kg
- Mixed-layer CIN
- -77 J/kg
- Mixed-layer LCL
- 554 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 477 m²/s²
- 0-3 km storm-relative helicity
- 512 m²/s²
- Significant tornado parameter
- 2.0
- Supercell composite
- 23.9
The text
As transmitted, in the capitals the NWS used until 2016.
723
ACUS11 KWNS 132248
SWOMCD
SPC MCD 132247
OKZ000-TXZ000-140015-
MESOSCALE DISCUSSION 0512
NWS STORM PREDICTION CENTER NORMAN OK
0547 PM CDT FRI APR 13 2012
AREAS AFFECTED...MUCH OF WESTERN/CENTRAL/NORTHEAST OK
CONCERNING...TORNADO WATCH 160...
VALID 132247Z - 140015Z
THE SEVERE WEATHER THREAT FOR TORNADO WATCH 160 CONTINUES.
TORNADO WATCH 160 CONTINUES UNTIL 02Z. LARGE HAIL ASIDE...TORNADO
POTENTIAL MAY FURTHER INCREASE THROUGH SUNSET...ESPECIALLY ACROSS
SOUTHWEST/WEST-CENTRAL OK. WW 160 ADJACENT PORTIONS OF NORTHWEST
TX/EASTERN TX PANHANDLE ARE BEING MONITORED FOR AN ADDITIONAL WATCH
THIS EVENING.
SUPERCELLS CONTINUE TO DEVELOP/SPLIT OVER THE PAST FEW HOURS ACROSS
SOUTHWEST OK INTO MUCH OF CENTRAL OK...WITH LONGER-LIVED/SEVERE
PRODUCING EAST-NORTHEASTWARD MOVING RIGHT-MOVING SUPERCELLS. WITHIN
A CORRIDOR OF MODERATE INSTABILITY /1500-2500 J PER KG
MLCAPE/...VERY FAVORABLE WIND PROFILES WILL CONTINUE TO SUPPORT
LONG-LIVED SUPERCELLS CAPABLE OF LARGE HAIL/TORNADOES WITHIN THIS
SAME CORRIDOR...WITH A NORTHWARD EXPANSION INTO ADDITIONAL PORTIONS
OF WESTERN/NORTHERN OK AND PERHAPS ADJACENT NORTHWEST TX AS A LOW
LEVEL JET INCREASES AND FRONTAL BOUNDARY/DRYLINE AND ASSOCIATED
MOIST SECTOR RETREATS. REGARDING THE TORNADO THREAT...THE
AFOREMENTIONED SOUTHERLY LOW LEVEL JET IS EXPECTED TO STRENGTHEN
ESPECIALLY TOWARD/AFTER SUNSET. THIS LLJ INCREASE...COUPLED WITH A
MORE DISCRETE INITIATION/LONG-LIVED SUPERCELLULAR MODE AND MODIFYING
OUTFLOW-AIDED TRIPLE POINT...MAY LEAD TO A HEIGHTENED TORNADO THREAT
ESPECIALLY ACROSS SOUTHWEST/WEST-CENTRAL OK. THIS INCLUDES THE
POTENTIAL FOR A STRONG TORNADO.
..GUYER.. 04/13/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...TSA...OUN...LUB...AMA...
LAT...LON 34250016 34860023 36939732 36559509 35489574 35069711
34039882 34250016SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 13, 12:10 PM CDT | Mesoscale Discussion | SPC | Caddo, Canadian, Carter, Comanche, Cotton, Garvin and 9 more | 2 hr |
| Apr 13, 1:28 PM CDT | Tornado Watch | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Cherokee and 42 more | 8 hr |
| Apr 13, 3:39 PM CDT | Mesoscale Discussion | SPC | Alfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 27 more | 96 min |
| Apr 13, 6:06 PM CDT | Severe Thunderstorm Watch | SPC | Armstrong, Briscoe, Carson, Childress, Collingsworth, Cottle and 8 more | 7 hr |
Nearby
Mesoscale Discussions in Oklahoma, 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.