Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 683
The Storm Prediction Center issued this mesoscale discussion at May 3, 2012, 6:21 PM CDT for 15 counties in Texas. It was in force for 114 min.
The area
The outline as issued.
The facts
- Issued
- May 3, 2012, 6:21 PM CDT (23:21 UTC)
- Expired
- May 3, 2012, 8:15 PM CDT
- In force
- 114 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
Counties Coke County, TX, Crockett County, TX, Fisher County, TX, Haskell County, TX, Irion County, TX, Jones County, TX, Kinney County, TX, Knox County, TX, Maverick County, TX, Nolan County, TX, Sterling County, TX, Stonewall County, TX, Terrell County, TX, Tom Green County, TX, Val Verde County, TX
The radar
The San Angelo radar (KSJT), 38 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
Midland Regional, TX (KMAF), launched 12:00Z, 11.4 hours before the alert went out and 168 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
- 1361 J/kg
- Mixed-layer CIN
- -270 J/kg
- Mixed-layer LCL
- 1722 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 15 m²/s²
- 0-3 km storm-relative helicity
- 91 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
865
ACUS11 KWNS 032321
SWOMCD
SPC MCD 032321
TXZ000-040115-
MESOSCALE DISCUSSION 0683
NWS STORM PREDICTION CENTER NORMAN OK
0621 PM CDT THU MAY 03 2012
AREAS AFFECTED...BIG COUNTRY TO THE LOWER PECOS VALLEY OF WRN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 032321Z - 040115Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A CLUSTER OF TSTMS WILL MOVE ACROSS THE RIO GRANDE AND
ISOLATED TSTMS MAY FORM FARTHER N ALONG DRYLINE. ALTHOUGH LOW-LEVEL
FLOW IS WEAK...ENHANCED MID-LEVEL SWLYS ATTENDANT TO A MID-LEVEL
IMPULSE CENTERED OVER EL PASO...SHOULD BE SUFFICIENT FOR ORGANIZED
UPDRAFTS WITH A PRIMARY RISK OF LARGE HAIL. UNCERTAINTY OVER STORM
LONGEVITY INTO THE EVENING MAY PRECLUDE A WW ISSUANCE.
DISCUSSION...23Z SURFACE ANALYSIS PLACED A DRYLINE FROM HARDEMAN TO
BREWSTER COUNTIES. TSTM CLUSTERS OVER THE MTNS OF COAHUILA HAVE
RECENTLY SHIFTED ACROSS THE RIO GRANDE. DFX VAD WIND PROFILE DEPICTS
VERY WEAK WINDS THROUGH THE LOWEST 6 KM AGL...BUT SWLYS AOA 30 KT
EXIST AOA 7 KM. GIVEN PRESENCE OF STRONG INSTABILITY WITH MLCAPE OF
2500-4000 J/KG...MODIFIED RAP SOUNDINGS SUGGEST EFFECTIVE SHEAR IS
AROUND 30 KT. THIS WILL SUPPORT A RISK FOR LARGE HAIL WITHIN THE
STRONGER CORES THAT MOVE ACROSS THE BORDER. FARTHER N...TCU/SMALL
CBS HAVE FORMED ACROSS FISHER/STONEWELL COUNTIES. JAYTON TX PROFILER
INDICATES MODERATE SWLYS EXTENDING THROUGH THE MID-LEVELS. THE
COMBINATION OF STRONG INSTABILITY WITH EFFECTIVE SHEAR WILL SUPPORT
A RISK FOR MARGINAL SUPERCELL STRUCTURES HERE AS WELL. THE LONGEVITY
OF STORMS INTO THE EVENING IS UNCERTAIN AS MLCIN INCREASES WITH THE
ONSET OF NOCTURNAL COOLING.
..GRAMS.. 05/03/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...OUN...EWX...SJT...LUB...MAF...
LAT...LON 29640278 30730192 32330080 33620004 33949966 33929927
33309936 31620026 30320092 29220030 28780023 28620043
29640151 29640278Nearby
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.