[MCD] SWOMCD

Mon Jul 3 11:42:03 UTC 2006

ACUS11 KWNS 031142
SWOMCD
SPC MCD 031142 
LAZ000-TXZ000-031445-

MESOSCALE DISCUSSION 1424
NWS STORM PREDICTION CENTER NORMAN OK
0642 AM CDT MON JUL 03 2006

AREAS AFFECTED...PORTIONS SE TX AND EXTREME SWRN LA.

CONCERNING...HEAVY RAINFALL 

VALID 031142Z - 031445Z

HAZARD FROM HEAVY RAINFALL SHOULD INCREASE DURING NEXT 1-2 HOURS
OVER PORTIONS GALVESTON/CHAMBERS/LIBERTY
COUNTIES...SHIFTING/EXPANDING INLAND ACROSS PORTIONS SAN
JACINTO/HARDIN/POLK/TYLER COUNTIES THROUGH AT LEAST 15Z.  RAIN RATES
1-2 INCHES/HOUR WILL BE COMMON WITH LOCAL 3 INCH/HOUR RATES POSSIBLE
IN HEAVIEST CORES.  MERGING/TRAINING OF CORES ALSO WILL ENHANCE
HEAVY RAIN THREAT.  ISOLATED RATES TO AROUND 2 INCHES/HOUR ARE
EXPECTED EWD TOWARD SABINE RIVER.

AS OF 1125Z...TSTMS ARE INCREASING IN COVERAGE AND INTENSITY FROM
SWRN CORNER GALVESTON COUNTY SSWWD TO AROUND 55 SE PSX...AND TO
SOMEWHAT LESSER DEGREE IN A SEPARATE CLUSTER FROM CHAMBERS COUNTY
NWWD THROUGH LIBERTY COUNTY.  ALL THIS CONVECTION SHOULD CONTINUE TO
FILL IN AND MOVE NNEWD ACROSS AREAS IMMEDIATELY SURROUNDING GLS BAY
AND FROM NRN SHORE OF BAY NEARLY TO LFK...AND EWD TO SABINE RIVER
AREA BETWEEN BPT-LCH.  PRIMARY BAND OF TSTMS IS BUILDING IN ZONE OF
VERY WEAK CAPPING INVOF SFC CONVERGENCE AXIS AND INVERTED TROUGH NOW
ANALYZED FROM LIBERTY COUNTY SSWWD TO NEAR BUOY 42019...AND SHOULD
CONTINUE TO DEVELOP/EXPAND INLAND.

ALREADY VERY MOIST AIR MASS SHOULD BECOME EXTREMELY SO WITH
TIME...AND FAVORABLE BUOYANCY WILL SUPPORT HEAVY RAINFALL PRODUCTION
IN TSTMS.  ANALYSIS OF GPS DERIVED MOISTURE DATA BETWEEN GLS-LCH
INDICATES ONSHORE PW VALUES AROUND 2.25 INCHES...WITH HIGHER VALUES
LIKELY OFFSHORE BASED ON SFC BUOY DATA AND RUC SOUNDINGS.  MODIFIED
00Z RAOBS AND RUC SOUNDINGS YIELD MLCAPES TO NEAR 2000 J/KG FROM GLS
BAY SWD OVER GULF AND EWD TO VICINITY BPT.  DEPTH OF SUPERFREEZING
LAYER -- ALMOST TO 500 MB FOR HIGHEST-THETAE LIFTED PARCEL -- AND
LARGE AMOUNT OF WARM-CLOUD BUOYANCY ALSO INDICATE POTENTIAL FOR
EFFICIENT PRECIP GENERATION.

..EDWARDS.. 07/03/2006

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

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

28759533 29399505 29899494 30519512 30929503 31049447
30929389 30499361 30069356 29709373 29629392 29449436
28909482 

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