Alert archive / Texas / Mesoscale Discussions in 2008

Mesoscale Discussion 113

January 30, 20084 parishes in Louisiana; 45 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jan 30, 2008, 11:47 PM CST for 4 parishes in Louisiana; 45 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jan 30, 2008, 11:47 PM CST (05:47 UTC)
Expired: Jan 31, 2008, 2:15 AM CST
In force: 2 hr
Issued by: the Storm Prediction Center

All 49 counties

Bossier Parish, LA, Caddo Parish, LA, De Soto Parish, LA, Sabine Parish, LA, Anderson County, TX, Angelina County, TX, Brazos County, TX, Burleson County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Falls County, TX, Franklin County, TX, Freestone County, TX, Gregg County, TX, Grimes County, TX, Hardin County, TX, Harrison County, TX, Henderson County, TX, Hopkins County, TX, Houston County, TX, Jasper County, TX, Kaufman County, TX, Leon County, TX, Liberty County, TX, Limestone County, TX, Madison County, TX, Marion County, TX, Montgomery County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Polk County, TX, Rains County, TX, Robertson County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Trinity County, TX, Tyler County, TX, Upshur County, TX, Van Zandt County, TX, Walker County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 160 km from the middle of the area, began a volume at 05:50 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

Shreveport, LA (KSHV), launched 00:00Z, 5.8 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2591 m above ground
0-6 km bulk shear: 73 kt
0-1 km storm-relative helicity: 150 m²/s²
0-3 km storm-relative helicity: 216 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 310548
SWOMCD
SPC MCD 310547 
LAZ000-ARZ000-TXZ000-310815-

MESOSCALE DISCUSSION 0113
NWS STORM PREDICTION CENTER NORMAN OK
1147 PM CST WED JAN 30 2008

AREAS AFFECTED...ERN TX INTO FAR WRN LA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 310547Z - 310815Z

ELEVATED TSTMS ARE EXPECTED TO INCREASE ACROSS THE DISCUSSION AREA
BETWEEN 07-10Z.  ISOLATED...MARGINALLY SEVERE HAIL WILL BE POSSIBLE
WITH THE MOST INTENSE CELLS.  A WW IS NOT ANTICIPATED.

RUC OBJECTIVE FIELDS AND GOES SOUNDER IPW DATA SHOW CONSIDERABLE
LOW-LEVEL MOISTURE FLUX OCCURRING FROM THE MIDDLE/UPPER TX COAST NWD
ACROSS ERN TX/WRN LA ALONG EXPANDING AND STRENGTHENING LLJ AXIS. 
ONGOING TSTMS OVER PORTIONS OF NWRN LA AS OF 0531Z ARE OCCURRING
ALONG ERN EDGE OF LLJ...PERHAPS IN ASSOCIATION WITH A LEAD MIDLEVEL
IMPULSE TRANSLATING EWD INTO THE LOWER MS VALLEY.

MORE ROBUST...ELEVATED TSTM DEVELOPMENT IS EXPECTED BETWEEN 07-10Z
AS STRONGER DEEP-LAYER FORCING FOR ASCENT ATTENDANT TO INTENSIFYING
UPPER TROUGH OVER THE SRN HIGH PLAINS SPREADS SEWD ACROSS REGION. 
CONTINUED MOISTENING AROUND 850 MB COUPLED WITH STEEPENING MIDLEVEL
LAPSE RATES WILL RESULT IN THE DEVELOPMENT OF MODEST ELEVATED
INSTABILITY WITH MUCAPES INCREASING TO 500-900 J/KG.  THIS
DESTABILIZATION IN CONJUNCTION WITH 40-50 KT OF EFFECTIVE BULK SHEAR
SUGGEST THE POTENTIAL FOR LONGER-LIVED...ROTATING UPDRAFTS.  DESPITE
THE MARGINAL INSTABILITY...SOME SEVERE HAIL WILL BE POSSIBLE GIVEN
THE POTENTIAL FOR SUPERCELL STRUCTURES AND RELATIVELY COOL
THERMODYNAMIC PROFILES.

..MEAD.. 01/31/2008

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

ATTN...WFO...LCH...SHV...HGX...FWD...

29929545 30299652 31089715 32129687 32909615 33349527
33249434 32989371 32439343 31429355 30279435 30009460

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 31, 5:23 AM CST	Mesoscale Discussion	SPC	Beauregard, Calcasieu, Cameron	3 hr
Jan 31, 5:51 AM CST	Tornado Watch	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Cameron and 10 more	7 hr
Jan 31, 9:57 AM CST	Mesoscale Discussion	SPC	Cameron	2 hr
Jan 31, 12:06 PM CST	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, Iberia, Iberville, Jefferson and 15 more	54 min
Jan 31, 12:35 PM CST	Tornado Watch	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 22 more	6 hr
Jan 31, 3:25 PM CST	Mesoscale Discussion	SPC	Ascension, Assumption, Livingston, Orleans, Saint Bernard, Saint Charles and 5 more	95 min

Nearby

Mesoscale Discussions in Texas, 2008 Mesoscale Discussions in Louisiana, 2008 Every mesoscale discussion in 2008

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.