Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS11 KWNS 190556
SPC MCD 190556
Mesoscale Discussion 0073
NWS Storm Prediction Center Norman OK
1156 PM CST Wed Jan 18 2017
Areas affected...southwest through central Louisiana into southwest
Concerning...Severe potential...Watch unlikely
Valid 190556Z - 190800Z
Probability of Watch Issuance...20 percent
SUMMARY...Threat for a couple instances of damaging wind and a brief
tornado will exist into the early morning from southwest through
central Louisiana into southwest Mississippi. Threat does not appear
sufficient for a WW, but area will continue to be monitored.
DISCUSSION...Some increase in thunderstorm organization and coverage
has been recently observed over southern LA into the northwest Gulf.
Uptick in convection appears to be in association to a modest
increase in the southwesterly low-level jet which will persist into
the morning hours in response to an upstream impulse. The marginal
thermodynamic environment with weak lapse rates and MLCAPE below 500
J/kg will remain the primary limiting factor. Moreover, while some
increase in vertical shear will occur, low-level hodograph size is
not expected to become exceptionally large. Nevertheless, the
kinematic environment will be sufficient for storms to develop at
least marginal supercell structures, especially as they move
northeast and interact with the stationary boundary across
south-central LA into southwest MS.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 30429318 31799182 32469055 31839014 31189065 30629162