Alert archive / Texas / Mesoscale Discussions in 2012
Mesoscale Discussion 738
The Storm Prediction Center issued this mesoscale discussion at May 6, 2012, 6:05 PM CDT for 22 counties in Texas. It was in force for 55 min.
The area
The outline as issued.
The facts
- Issued
- May 6, 2012, 6:05 PM CDT (23:05 UTC)
- Expired
- May 6, 2012, 7:00 PM CDT
- In force
- 55 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 22 counties
Angelina County, TX, Austin County, TX, Cherokee County, TX, Grimes County, TX, Hardin County, TX, Harris County, TX, Houston County, TX, Jasper County, TX, Liberty County, TX, Madison County, TX, Montgomery County, TX, Nacogdoches County, TX, Polk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Trinity County, TX, Tyler County, TX, Walker County, TX, Waller County, TX, Washington County, TX
The radar
The Houston radar (KHGX), 140 km from the middle of the area, began a volume at 23:06 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
Lake Charles Mun, LA (KLCH), launched 12:00Z, 11.1 hours before the alert went out and 193 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
- 1142 J/kg
- Mixed-layer CIN
- -82 J/kg
- Mixed-layer LCL
- 894 m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 32 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
319
ACUS11 KWNS 062305
SWOMCD
SPC MCD 062305
LAZ000-TXZ000-070000-
MESOSCALE DISCUSSION 0738
NWS STORM PREDICTION CENTER NORMAN OK
0605 PM CDT SUN MAY 06 2012
AREAS AFFECTED...E TX
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 062305Z - 070000Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...A CLUSTER OF MARGINALLY SEVERE STORMS AND HEAVY RAINFALL
IS BEGINNING TO FORM EAST OF LHB AND NORTHWEST OF DWH. A WW IS NOT
CURRENTLY ANTICIPATED.
DISCUSSION...THUNDERSTORMS ARE BEGINNING TO INCREASE AHEAD OF A
WEAKENED MCV...A RESULT OF YESTERDAY/S CONVECTION ACROSS CNTRL TX.
THIS CONVECTIVE DEVELOPMENT IS OCCURRING IN A RELATIVELY MOIST AND
MODERATELY UNSTABLE AIR MASS...EAST OF WHERE MIXING HAS RESULTED IN
A SUBTLE DEW POINT GRADIENT NEAR LHB. PROFILER DATA INDICATES
MID-LEVEL WINDS ARE SOMEWHAT STRONGER THAN SURROUNDING AREAS OWING
TO THE SUBTLE UPPER WAVE PROGRESSING THROUGH CNTRL/E CNTRL TX. AS A
RESULT...A SEMI-ORGANIZED CLUSTER OF THUNDERSTORMS MAY DEVELOP AND
DRIFT EWD...WITH INITIAL THREATS OF DMGG WIND AND HAIL. GIVEN THE
CLIMATOLOGICALLY HIGH PWAT AIR MASS...THE PRIMARY THREAT SHOULD
QUICKLY TRANSITION TO HEAVY RAINFALL.
..HURLBUT/THOMPSON.. 05/06/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LCH...SHV...HGX...FWD...
LAT...LON 30289652 31729552 32089464 31879412 31339375 30369374
29819433 29729531 29869638 30289652SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 5, 8:22 PM CDT | Mesoscale Discussion | SPC | Blanco, Brown, Burnet, Coleman, Comanche, Concho and 11 more | 53 min |
| May 6, 5:15 PM CDT | Mesoscale Discussion | SPC | Baylor, Brown, Burnet, Callahan, Coke, Coleman and 21 more | 60 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.