Alert archive / Texas / Mesoscale Discussions in 2003

Mesoscale Discussion 2146

August 11, 200327 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Aug 11, 2003, 5:16 PM CDT for 27 counties in Texas. It was in force for 59 min.

The area

The outline as issued.

The facts

Issued
Aug 11, 2003, 5:16 PM CDT (22:16 UTC)
Expired
Aug 11, 2003, 6:15 PM CDT
In force
59 min
Issued by
the Storm Prediction Center
All 27 counties

Anderson County, TX, Angelina County, TX, Austin County, TX, Brazoria County, TX, Brazos County, TX, Chambers County, TX, Cherokee County, TX, Colorado County, TX, Fort Bend County, TX, Freestone County, TX, Galveston County, TX, Grimes County, TX, Harris County, TX, Houston County, TX, Jackson County, TX, Leon County, TX, Liberty County, TX, Madison County, TX, Matagorda County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Trinity County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 104 km from the middle of the area, began a volume at 22:16 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, 10.3 hours before the alert went out and 250 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.

Skew-T log-pSkew-T log-p diagram, Lake Charles Mun, LA at 12:00Z on 2003-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1341 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 12:00Z on 2003-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 6 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1341 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
1100 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
6 m²/s²
0-3 km storm-relative helicity
63 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
ACUS11 KWNS 112217
SWOMCD
SPC MCD 112216 
TXZ000-112315-

MESOSCALE DISCUSSION 2146
NWS STORM PREDICTION CENTER NORMAN OK
0516 PM CDT MON AUG 11 2003

AREAS AFFECTED...SOUTHEAST TEXAS

CONCERNING...SEVERE THUNDERSTORM WATCH 856...

VALID 112216Z - 112315Z

THUNDERSTORM COMPLEX NOW APPROACHING VCT HAS LARGE...WELL-DEVELOPED
COLD POOL.  THIS FEATURE SHOULD CONTINUE TO MOVE/DEVELOP SSW DURING
THE NEXT FEW HOURS.  THREAT FOR ADDITIONAL SURFACE-BASED ACTIVITY IN
AREA BETWEEN HOU AND VCT SHOULD REMAIN MINIMAL DURING THIS PERIOD.

JUST N OF WW...WIDELY SCATTERED STORMS CONTINUE TO DEVELOP ABOVE
SHALLOW LAYER OF COOL AIR IN AREA BETWEEN ACT AND LFK. GIVEN
MODERATE NNELY FLOW IN THE STORM-BEARING LAYER...THIS ACTIVITY WILL
LIKELY MOVE SSW INTO REGION W/N OF HOU DURING THE NEXT SEVERAL
HOURS. SEVERE THREAT WITH THIS ACTIVITY SHOULD...HOWEVER...BE
MINIMAL AND WW 856 WILL EXPIRE AS SCHEDULED AT 2300 UTC.

..CORFIDI.. 08/11/2003

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LCH...SHV...HGX...FWD...CRP...EWX...

28449656 28949676 30109678 30719650 31449632 32069609
32119489 31309454 30259451 29429455 28879550

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 11, 11:31 AM CDTMesoscale DiscussionSPCAustin, Bastrop, Brazoria, Brazos, Burleson, Caldwell and 27 more89 min
Aug 11, 12:05 PM CDTSevere Thunderstorm WatchSPCAustin, Brazoria, Colorado, Fort Bend, Galveston, Harris and 8 more6 hr
Aug 11, 2:06 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Collin, Cooke, Dallas and 31 more54 min
Aug 11, 2:31 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bandera, Bastrop, Bee, Bexar and 44 more29 min
Aug 11, 2:35 PM CDTSevere Thunderstorm WatchSPCAtascosa, Bandera, Bastrop, Bee, Bexar, Blanco and 21 more5 hr
Aug 11, 4:45 PM CDTSevere Thunderstorm WatchSPCBosque, Clay, Collin, Comanche, Cooke, Dallas and 17 more5 hr
Aug 11, 5:29 PM CDTMesoscale DiscussionSPCCollin, Dallas, Ellis, Grayson, Navarro, Rockwall2 hr
Aug 11, 6:09 PM CDTMesoscale DiscussionSPCAransas, Atascosa, Bandera, Bastrop, Bee, Bexar and 42 more96 min

Nearby

Mesoscale Discussions in Texas, 2003Every mesoscale discussion in 2003

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.