J-Money Mesoscale Analysis as of 1830z:

Two regional short-wave features to note in the 700-500 mb layer this afternoon, as per water vapor imagery and meso-analysis data.  The leading system was near the TX/LA border and pushing east, with associated storms being heavy rain producers, given saturated, weakly sheared environment.  Houston LMA and flash rate density products show a fair amount of lightning as well.

Through 19-22z, better convective potential may shift to central/south TX, as a subtle 700 mb short-wave over west TX moves in.  This may interact with a decelerating outflow boundary in the vicinity.  Layered PW data depicts the leading edge of mid-level dry air and presumably steeper lapse rates as well.  Main question is can strong 700 mb cap shown on 12z KDRT sounding be overcome.  Time will tell.   Maybe 19z NUCAPS could help later today?