Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 1289
The Storm Prediction Center issued this mesoscale discussion at Jun 26, 2012, 2:02 PM CDT for 55 counties in Texas. It was in force for 118 min.
The area
The outline as issued.
The facts
- Issued
- Jun 26, 2012, 2:02 PM CDT (19:02 UTC)
- Expired
- Jun 26, 2012, 4:00 PM CDT
- In force
- 118 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 60%
All 55 counties
Atascosa County, TX, Austin County, TX, Bandera County, TX, Bastrop County, TX, Bee County, TX, Bexar County, TX, Blanco County, TX, Brazoria County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Calhoun County, TX, Colorado County, TX, Comal County, TX, DeWitt County, TX, Dimmit County, TX, Duval County, TX, Fayette County, TX, Fort Bend County, TX, Frio County, TX, Goliad County, TX, Gonzales County, TX, Grimes County, TX, Guadalupe County, TX, Harris County, TX, Hays County, TX, Jackson County, TX, Karnes County, TX, Kendall County, TX, La Salle County, TX, Lavaca County, TX, Lee County, TX, Live Oak County, TX, Madison County, TX, Matagorda County, TX, McMullen County, TX, Medina County, TX, Milam County, TX, Montgomery County, TX, Refugio County, TX, Robertson County, TX, San Jacinto County, TX, San Patricio County, TX, Travis County, TX, Trinity County, TX, Uvalde County, TX, Victoria County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Webb County, TX, Wharton County, TX, Williamson County, TX, Wilson County, TX, Zavala County, TX
The radar
The Austin/San Antonio radar (KEWX), 32 km from the middle of the area, began a volume at 18:59 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
Corpus Christi, TX (KCRP), launched 12:00Z, 7.0 hours before the alert went out and 200 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
- 1292 J/kg
- Mixed-layer CIN
- -172 J/kg
- Mixed-layer LCL
- 1814 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 21 m²/s²
- 0-3 km storm-relative helicity
- 107 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted, in the capitals the NWS used until 2016.
182
ACUS11 KWNS 261903
SWOMCD
SPC MCD 261902
TXZ000-262100-
MESOSCALE DISCUSSION 1289
NWS STORM PREDICTION CENTER NORMAN OK
0202 PM CDT TUE JUN 26 2012
AREAS AFFECTED...S-CNTRL/SERN TX
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 261902Z - 262100Z
PROBABILITY OF WATCH ISSUANCE...60 PERCENT
SUMMARY...AT LEAST ISOLATED HIGH-BASED TSTMS SHOULD FORM WITHIN A
HOT THERMODYNAMIC ENVIRONMENT BY LATE AFTERNOON. WITH MODERATE
MID-LEVEL NELYS...UPDRAFTS COULD COALESCE INTO AN ORGANIZED CLUSTER
WITH THREATS OF ISOLATED SEVERE WIND AND HAIL.
DISCUSSION...CU HAS INCREASED IN THE PAST HOUR IN VISIBLE SATELLITE
IMAGERY ALONG THE COASTAL PLAIN AND HILL COUNTRY. PRESENCE OF
SCATTERED CIRRUS SUGGESTS A SUBTLE UPPER-LEVEL IMPULSE ALONG THE WRN
GULF COAST MAY BE ENHANCING ASCENT. WITH SURFACE TEMPERATURES NOW
REACHING 100-105...MLCIN SHOULD BE WEAK WITH A DEEPLY-MIXED BOUNDARY
LAYER PER ACARS DATA INVOF AUS. GUIDANCE IS FAIRLY CONSISTENT THAT
TSTMS SHOULD FORM...ALTHOUGH THE LACK OF WELL-DEFINED
SURFACE/UPPER-LEVEL FEATURES BREEDS UNCERTAINTY IN WHERE DEVELOPMENT
WILL FOCUS. NEVERTHELESS...PRESENCE OF 30-35 KT MID-LEVEL NELYS
SAMPLED IN THE LEDBETTER TX PROFILER WOULD BE SUFFICIENT FOR
ORGANIZING UPDRAFTS. THE STEEP LAPSE RATE ENVIRONMENT SHOULD PROMOTE
RISKS FOR SEVERE WIND AND SOME HAIL.
..GRAMS/WEISS.. 06/26/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...HGX...FWD...CRP...EWX...
LAT...LON 29779993 30519839 31169694 31319508 30339483 29149531
27999721 27599886 27869963 28460022 29090042 29779993SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 26, 3:22 PM CDT | Severe Thunderstorm Watch | SPC | Atascosa, Austin, Bastrop, Bee, Bexar, Brazos and 35 more | 7 hr |
| Jun 26, 6:58 PM CDT | Mesoscale Discussion | SPC | Atascosa, Austin, Bastrop, Bee, Bexar, Brazos and 35 more | 62 min |
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.