SPC MD 1566

MD 1566 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHEAST LA AND ADJACENT SOUTHERN MS

Mesoscale Discussion 1566
NWS Storm Prediction Center Norman OK
0312 AM CDT Tue Aug 25 2020

Areas affected...portions of southeast LA and adjacent southern MS

Concerning...Severe potential...Watch unlikely 

Valid 250812Z - 251015Z

Probability of Watch Issuance...20 percent

SUMMARY...A brief, weak tornado and/or waterspout is possible near
the immediate coast. However, the overall threat is expected to
remain low, and diminish with time through the morning hours.

DISCUSSION...Occasional low level rotation has been noted in cells
tracing northwest from near the southeast LA/MS coasts toward the
Slidell LA vicinity. While low level hodographs initially appear
enlarged, when adjusted for storm motion, SRH values become somewhat
lower, with 0-1 km SRH around 80-100 m2/s2. Furthermore, away from
the immediate coast, surface dewpoints lower a few degrees, from
around 77-79 degrees, to 73-76 degrees. As a result, low-level
instability quickly diminishes inland. With time, low-to-midlevel
flow fields are expected to further weaken as TD Marco continues to
diminish, becoming more of an open surface trough. While additional
cells offshore will continue tracking northwest and may continue to
exhibit sporadic low-level rotation, the overall tornado threat is
expected to remain limited in both time and space.

..Leitman/Edwards.. 08/25/2020

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

ATTN...WFO...LIX...

LAT...LON   29498867 29448903 29848995 30179028 30389031 30589017
            30648995 30618959 30538942 30338904 29958863 29648860
            29498867 

Read more

from SPC Forecast Products http://www.spc.noaa.gov/products/md/md1566.html