Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 2045
The Storm Prediction Center issued this mesoscale discussion at Oct 13, 2012, 12:23 PM CDT for 8 counties in Oklahoma; 19 counties in Texas. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 13, 2012, 12:23 PM CDT (17:23 UTC)
- Expired
- Oct 13, 2012, 3:00 PM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 27 counties
Caddo County, OK, Comanche County, OK, Custer County, OK, Greer County, OK, Jackson County, OK, Kiowa County, OK, Tillman County, OK, Washita County, OK, Baylor County, TX, Coke County, TX, Fisher County, TX, Foard County, TX, Hardeman County, TX, Haskell County, TX, Howard County, TX, Jones County, TX, Kent County, TX, King County, TX, Knox County, TX, Mitchell County, TX, Nolan County, TX, Scurry County, TX, Stonewall County, TX, Taylor County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX
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, 5.4 hours before the alert went out and 226 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
- 885 J/kg
- Mixed-layer CIN
- -162 J/kg
- Mixed-layer LCL
- 683 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 341 m²/s²
- 0-3 km storm-relative helicity
- 365 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 8.7
The text
As transmitted, in the capitals the NWS used until 2016.
747
ACUS11 KWNS 131724
SWOMCD
SPC MCD 131723
OKZ000-TXZ000-132000-
MESOSCALE DISCUSSION 2045
NWS STORM PREDICTION CENTER NORMAN OK
1223 PM CDT SAT OCT 13 2012
AREAS AFFECTED...BIG COUNTRY OF NWRN TX...SWRN OK
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 131723Z - 132000Z
PROBABILITY OF WATCH ISSUANCE...80 PERCENT
SUMMARY...TSTMS SHOULD INITIATE BY ABOUT 19Z ALONG THE COLD FRONT IN
NWRN TX. THIS INITIAL ACTIVITY SHOULD LARGELY BE DISCRETE AND
INTENSIFY THROUGH THE MID/LATE-AFTERNOON WITH SUPERCELL STRUCTURES
LIKELY. PRIMARY INITIAL RISK SHOULD BE LARGE HAIL...BUT A COUPLE OF
TORNADOES AND ISOLATED SEVERE WINDS ARE ALSO POSSIBLE.
DISCUSSION...17Z SURFACE ANALYSIS PLACED A COLD FRONT FROM NEAR DDC
TO CDS TO MAF. SW-NE ORIENTED BANDS OF CU WERE NOTED IN VISIBLE
IMAGERY INVOF THE FRONT WITH THE MOST PRONOUNCED AGITATION OCCURRING
NEAR CDS WHERE THE STRONGEST SURFACE HEATING HAS OCCURRED. MODIFIED
12Z AMA/MAF RAOBS SUGGEST THIS REGION IS ALREADY LARGELY UNCAPPED
WITH SURFACE TEMPERATURES HAVING WARMED INTO THE LOWER 80S. AS
MID-LEVEL HEIGHT FALLS CONTINUE ACROSS THE REGION DOWNSTREAM OF THE
SHORT WAVE TROUGH IN THE LEE OF THE SRN ROCKIES...TSTM INITIATION
APPEARS PROBABLE IN THE NEXT HOUR OR SO.
AS THE WARM SECTOR AIR MASS CONTINUES TO DESTABILIZE...ALBEIT WITHIN
A RELATIVELY NARROW CORRIDOR GIVEN DOWNSTREAM WEAK CONVECTION ACROSS
CNTRL OK...TSTMS ALONG THE FRONT WILL INTENSIFY. EFFECTIVE SHEAR OF
AROUND 40-50 KT WILL FAVOR SUPERCELL STRUCTURES WITH LARGE HAIL AS
THE PRIMARY THREAT. WHILE STRONGER LOW-LEVEL FLOW SHOULD LARGELY
REMAIN E OF THE INITIAL FRONTAL DEVELOPMENT...A TORNADO OR TWO IS
PLAUSIBLE WITH RELATIVELY LOW LCL HEIGHTS AND MODERATE 0-1 KM SRH.
..GRAMS/THOMPSON.. 10/13/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...FWD...OUN...SJT...LUB...MAF...
LAT...LON 35519954 35779913 35749858 35599833 35269825 34429834
33179907 32309974 31800075 32190164 32790108 34449986
35519954SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 12, 10:11 PM CDT | Mesoscale Discussion | SPC | Beaver, Cimarron, Texas | 94 min |
| Oct 12, 11:52 PM CDT | Mesoscale Discussion | SPC | Beaver, Cimarron, Harper, Texas | 83 min |
| Oct 13, 2:06 AM CDT | Mesoscale Discussion | SPC | Beaver, Harper | 84 min |
| Oct 13, 1:00 PM CDT | Tornado Watch | SPC | Alfalfa, Atoka, Blaine, Bryan, Caddo, Canadian and 36 more | 8 hr |
| Oct 13, 2:55 PM CDT | Mesoscale Discussion | SPC | Atoka, Blaine, Bryan, Caddo, Canadian, Carter and 33 more | 95 min |
| Oct 13, 5:57 PM CDT | Tornado Watch | SPC | Adair, Cherokee, Choctaw, Craig, Creek, Delaware and 19 more | 6 hr |
| Oct 13, 6:59 PM CDT | Mesoscale Discussion | SPC | Adair, Atoka, Bryan, Carter, Cherokee, Choctaw and 35 more | 2 hr |
| Oct 12, 9:19 PM CDT | Mesoscale Discussion | SPC | Armstrong, Bailey, Briscoe, Carson, Castro, Cochran and 20 more | 56 min |
| Oct 12, 11:34 PM CDT | Mesoscale Discussion | SPC | Andrews, Bailey, Cochran, Crosby, Dawson, Floyd and 9 more | 86 min |
| Oct 13, 1:10 PM CDT | Mesoscale Discussion | SPC | Coke, Concho, Crockett, Irion, Menard, Reagan and 7 more | 95 min |
| Oct 13, 1:37 PM CDT | Severe Thunderstorm Watch | SPC | Brown, Coke, Coleman, Concho, Crockett, Edwards and 19 more | 9 hr |
| Oct 13, 3:42 PM CDT | Mesoscale Discussion | SPC | Coke, Crockett, Irion, Kinney, Maverick, Reagan and 6 more | 93 min |
| Oct 13, 6:30 PM CDT | Mesoscale Discussion | SPC | Angelina, Austin, Bastrop, Bexar, Brazos, Burleson and 27 more | 60 min |
Nearby
Mesoscale Discussions in Texas, 2012Mesoscale Discussions in Oklahoma, 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.