Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 856
The Storm Prediction Center issued this mesoscale discussion at May 20, 2012, 7:32 PM CDT for 6 counties in Texas. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- May 20, 2012, 7:32 PM CDT (00:32 UTC)
- Expired
- May 20, 2012, 9:00 PM CDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
Counties Dickens County, TX, Haskell County, TX, Kent County, TX, King County, TX, Knox County, TX, Stonewall County, TX
The radar
The Dyess AFB radar (KDYX), 136 km from the middle of the area, began a volume at 00:34 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
Midland Regional, TX (KMAF), launched 00:00Z, 0.5 hours before the alert went out and 232 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
- 210 J/kg
- Mixed-layer CIN
- -268 J/kg
- Mixed-layer LCL
- 2495 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 102 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
The text
As transmitted, in the capitals the NWS used until 2016.
266
ACUS11 KWNS 210032
SWOMCD
SPC MCD 210032
TXZ000-210200-
MESOSCALE DISCUSSION 0856
NWS STORM PREDICTION CENTER NORMAN OK
0732 PM CDT SUN MAY 20 2012
AREAS AFFECTED...PARTS OF NW TX
CONCERNING...SEVERE THUNDERSTORM WATCH 286...
VALID 210032Z - 210200Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 286
CONTINUES.
SUMMARY...WW 286 PROBABLY SHOULD BE CONTINUED AT LEAST ANOTHER HOUR
OR TWO...BUT IT COULD BE CANCELLED PRIOR TO SCHEDULED 04Z EXPIRATION
IF CURRENT TRENDS CONTINUE.
DISCUSSION...INITIAL STORM...NEAR INTERSECTION OF CONVECTIVE OUTFLOW
AND SURFACE FRONTAL ZONE...HAS DISSIPATED SOUTHWEST OF WICHITA
FALLS...BUT ISOLATED TO WIDELY SCATTERED NEW CONVECTIVE DEVELOPMENT
CONTINUES ALONG THE SURFACE FRONT EXTENDING WEST SOUTHWESTWARD
TOWARD THE LUBBOCK AREA. ALTHOUGH CAPE IS STILL MODERATELY LARGE
AND INHIBITION APPEARS WEAK...ACTIVITY HAS REMAINED SOMEWHAT
SUPPRESSED...EVEN IN THE PRESENCE OF SUFFICIENT SHEAR FOR
SUPERCELLS...BENEATH 30+ KT NORTHWESTERLY 500 MB FLOW. SUPPORT FOR
A SUBSTANTIAL FURTHER INCREASE IN STORM COVERAGE AND INTENSITY PRIOR
TO THE ONSET OF MORE RAPID BOUNDARY LAYER COOLING IS NOT OBVIOUS.
HOWEVER...ISOLATED NEW STORM DEVELOPMENT STILL DOES NOT APPEAR OUT
OF THE QUESTION THROUGH 01-02Z...PARTICULARLY ALONG AND JUST NORTH
OF THE FRONT...TO THE EAST SOUTHEAST OF LUBBOCK...WHERE LINGERING
BOUNDARY LAYER INSTABILITY REMAINS STRONGEST.
..KERR.. 05/21/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...SJT...LUB...
LAT...LON 33240130 33630090 33689968 33719933 32999960 33060018
33140053 33240130SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 12:59 PM CDT | Mesoscale Discussion | SPC | Bailey, Castro, Dallam, Deaf Smith, Hartley, Moore and 2 more | 91 min |
| May 21, 3:24 PM CDT | Severe Thunderstorm Watch | SPC | Bailey, Castro, Dallam, Deaf Smith, Hale, Hartley and 8 more | 8 hr |
Nearby
Mesoscale 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.