Alert archive / Texas / Mesoscale Discussions in 2004

Mesoscale Discussion 29

January 24, 2004Sabine Parish, Louisiana; 23 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jan 24, 2004, 10:46 PM CST for Sabine Parish, Louisiana; 23 counties in Texas. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued
Jan 24, 2004, 10:46 PM CST (04:46 UTC)
Expired
Jan 25, 2004, 12:15 AM CST
In force
89 min
Issued by
the Storm Prediction Center
All 24 counties

Sabine Parish, LA, Angelina County, TX, Austin County, TX, Brazoria County, TX, Chambers County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Hardin County, TX, Harris County, TX, Jackson County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Matagorda County, TX, Montgomery County, TX, Newton County, TX, Polk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Tyler County, TX, Waller County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 83 km from the middle of the area, began a volume at 04:49 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 00:00Z, 4.8 hours before the alert went out and 202 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 00:00Z on 2004-01-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 78 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 00:00Z on 2004-01-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 223 square meters per square second.1939587897Sfc1 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
78 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
558 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
223 m²/s²
0-3 km storm-relative helicity
238 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

557 
ACUS11 KWNS 250446
SWOMCD
SPC MCD 250446 
LAZ000-TXZ000-250615-

MESOSCALE DISCUSSION 0029
NWS STORM PREDICTION CENTER NORMAN OK
1046 PM CST SAT JAN 24 2004

AREAS AFFECTED...SERN TX/WRN LA

CONCERNING...TORNADO WATCH 1...

VALID 250446Z - 250615Z

ISOLATED SEVERE STORMS REMAIN POSSIBLE...THOUGH SHALLOW/STABLE
BOUNDARY LAYER IS LIMITING OVERALL SEVERE THREAT.  IF CURRENT TRENDS
CONTINUE...WW WILL BE ALLOWED TO EXPIRE AT 06Z.

THUNDERSTORM COVERAGE WILL CONTINUE TO EXPAND FROM SERN TX INTO WRN
LA THROUGH 06-08Z...AS INCREASING UVVS ASSOCIATED WITH A NEGATIVELY
TILTED SHORT WAVE TROUGH OVER CENTRAL TX SPREAD ACROSS WW 1 TO WRN
LA. 75 KT SWLY MID-LEVEL SPEED MAX MOVING NEWD ACROSS WW1 TO WRN LA
WILL CONTINUE TO SUPPORT ORGANIZED STORMS...WITH REGIONAL RADARS
SHOWING A FEW STORMS WITH LOW-LEVEL ROTATION.  OBJECTIVE ANALYSES
INDICATE A STABLE BOUNDARY LAYER ACROSS SERN TX INTO WRN LA WHICH
SUGGESTS CURRENT THUNDERSTORMS ARE SLIGHTLY ELEVATED. GIVEN STRENGTH
OF LOW AND DEEP LAYER SHEAR ACROSS THE REGION...ANY STORM WHICH CAN
ROOT INTO THE BOUNDARY LAYER WILL HAVE THE POTENTIAL TO PRODUCE
TORNADOES. HOWEVER..LOSS OF DAY TIME HEATING WILL LIKELY MAINTAIN
THE STABLE BOUNDARY LAYER...AND LIMIT THE SEVERE POTENTIAL TO MAINLY
HAIL AOB 1 INCH IN DIAMETER.

..PETERS.. 01/25/2004

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

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

29989639 30799525 31579435 31569341 28719452 28749682

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 25, 1:11 AM CSTMesoscale DiscussionSPCAcadia, Allen, Ascension, Avoyelles, Beauregard, Calcasieu and 15 more2 hr
Jan 25, 10:08 AM CSTMesoscale DiscussionSPCJefferson, Orleans, Saint Bernard3 hr
Jan 24, 7:56 PM CSTMesoscale DiscussionSPCAngelina, Austin, Brazoria, Chambers, Colorado, Fort Bend and 22 more94 min

Nearby

Mesoscale Discussions in Texas, 2004Mesoscale Discussions in Louisiana, 2004Every mesoscale discussion in 2004

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.