Mesoscale Discussion 0379
   NWS Storm Prediction Center Norman OK
   1113 PM CDT Mon Mar 27 2023

   Areas affected...Parts of mid/upper Texas coastal areas

   Concerning...Severe potential...Watch unlikely 

   Valid 280413Z - 280645Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Increasing thunderstorm development appears probable
   through 1-3 AM CDT.  This may include a few developing supercell
   structures which may become capable of producing at least marginally
   severe hail.  It is not clear that a severe weather watch is needed,
   but trends are being monitored.

   DISCUSSION...While low amplitude mid-level troughing within the
   primary belt of mid-latitude westerlies passes by well to the north
   (across the central Great Plains into lower Missouri Valley), a much
   more subtle perturbation of subtropical eastern Pacific origins is
   progressing east of the Texas Big Bend toward mid/upper Texas
   coastal areas.  Weak lower/mid tropospheric warm advection
   downstream of this feature already appears to be contributing to at
   least some increase in convective development across the coastal
   plain.  This probably will continue, with substantive further
   intensification possible during the next few hours with
   strengthening forcing for ascent aloft.

   Lower levels remain fairly moist, with Rapid Refresh forecast
   soundings indicating steep enough lapse rates aloft to support
   sizable CAPE (1000-2000+ J/kg for most unstable parcels).  However,
   even where surface dew points are near 70F in close proximity to the
   coast, developing thunderstorm activity may remain mostly rooted
   above a fairly deep saturated near-surface layer with stable lapse
   rates.   Additionally, environmental wind fields within the
   potential inflow layer are forecast to remain rather weak.
   Even so, shear through the elevated convective layer is strong and
   supportive of supercell structures, in the presence of thermodynamic
   profiles which appear conducive to the development of at least
   marginally severe hail in stronger storms.

   ..Kerr/Edwards.. 03/28/2023

   ...Please see www.spc.noaa.gov for graphic product...

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

   LAT...LON   29429715 30159560 30669356 29509271 28689414 28199667
               29429715