Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 2157
The Storm Prediction Center issued this mesoscale discussion at Dec 14, 2012, 5:21 PM CST for 13 counties in Oklahoma; 17 counties in Texas. It was in force for 84 min.
The area
The outline as issued.
The facts
- Issued
- Dec 14, 2012, 5:21 PM CST (23:21 UTC)
- Expired
- Dec 14, 2012, 6:45 PM CST
- In force
- 84 min
- Issued by
- the Storm Prediction Center
All 30 counties
Beckham County, OK, Caddo County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Dewey County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kiowa County, OK, Roger Mills County, OK, Tillman County, OK, Washita County, OK, Baylor County, TX, Childress County, TX, Collingsworth County, TX, Cottle County, TX, Dickens County, TX, Foard County, TX, Hall County, TX, Hardeman County, TX, Haskell County, TX, Hemphill County, TX, Kent County, TX, King County, TX, Knox County, TX, Stonewall County, TX, Wheeler County, TX, Wichita County, TX, Wilbarger County, TX
The radar
The Altus AFB radar (KFDR), 76 km from the middle of the area, began a volume at 23:20 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 nearest sounding before it
Amarillo Airport, TX (KAMA), launched 12:00Z, 11.4 hours before the alert went out and 191 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1556 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km storm-relative helicity
- 81 m²/s²
- 0-3 km storm-relative helicity
- 64 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
155
ACUS11 KWNS 142321
SWOMCD
SPC MCD 142321
OKZ000-TXZ000-150045-
MESOSCALE DISCUSSION 2157
NWS STORM PREDICTION CENTER NORMAN OK
0521 PM CST FRI DEC 14 2012
AREAS AFFECTED...ERN TX PANHANDLE...NW TX...WRN OK
CONCERNING...SEVERE THUNDERSTORM WATCH 681...
VALID 142321Z - 150045Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 681
CONTINUES.
SUMMARY...A SEVERE THREAT IS EXPECTED TO CONTINUE FOR A FEW MORE
HOURS ACROSS THE ERN TX PANHANDLE...NW TX INTO WRN OK. WIND DAMAGE
WILL LIKELY BE ASSOCIATED WITH THE LINE. AN ISOLATED TORNADO THREAT
WILL ALSO EXIST. AS THE LINE MOVES TO THE ERN EDGE OF WW 681...AN
EXTENSION IN AREA MAY BE NEEDED.
DISCUSSION...THE LATEST WATER VAPOR IMAGERY SHOWS A
NEGATIVELY-TILTED UPPER-LEVEL TROUGH OVER ERN NM WITH A POWERFUL 80
TO 100 KT MID-LEVEL JET MOVING OUT INTO WEST TX. DIFFLUENCE IN THE
EXIT REGION OF THE JET ALONG WITH STRONG LARGE-SCALE ASCENT IS
SUPPORTING A SQUALL-LINE ONGOING FROM THE ERN TX PANHANDLE SWD INTO
NW TX. AHEAD OF THE SQUALL-LINE...SFC DEWPOINTS ARE IN THE LOWER TO
MID 50S F AND WSR-88 VWPS SHOW 50 KT AT 1 KM ABOVE THE SFC. THIS
ENVIRONMENT ALONG WITH A 50 TO 60 KT EWD FORWARD SPEED OF THE LINE
SHOULD SUPPORT A WIND DAMAGE THREAT AS THE LINE MOVES EWD INTO THE
WRN OK OVER THE NEXT 1 TO 2 HOURS. 0-3 KM STORM RELATIVE HELICITIES
OF 400 TO 500 M2/S2 SHOULD ALSO SUPPORT AN ISOLATED TORNADO THREAT.
IN SPITE OF THESE FACTORS...THE CORRIDOR OF INSTABILITY IS VERY
NARROW WHICH SHOULD RESULT IN A GRADUAL WEAKENING OF THE LINE AFTER
DARK.
..BROYLES/MEAD.. 12/14/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...AMA...MAF...
LAT...LON 35830076 34720060 33580084 32880087 32849993 33279919
33889840 34699812 35689834 36049874 36100045 35830076SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 14, 2:12 PM CST | Mesoscale Discussion | SPC | Beaver, Beckham, Ellis, Roger Mills, Texas | 93 min |
| Dec 14, 2:28 PM CST | Severe Thunderstorm Watch | SPC | Beckham, Ellis, Greer, Harmon, Jackson, Roger Mills | 5 hr |
| Dec 14, 3:38 PM CST | Mesoscale Discussion | SPC | Beckham, Ellis, Greer, Harmon, Roger Mills | 97 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; radar from the NEXRAD Level II archive.