Severe Storm Outlook Narrative (AC)
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063
ACUS11 KWNS 210444
SWOMCD
SPC MCD 210444
MSZ000-LAZ000-210545-

Mesoscale Discussion 0083
NWS Storm Prediction Center Norman OK
1044 PM CST Fri Jan 20 2017

Areas affected...southeast Louisiana through southern Mississippi

Concerning...Severe potential...Watch needed soon

Valid 210444Z - 210545Z

Probability of Watch Issuance...95 percent

SUMMARY...Threat for a few tornadoes, damaging wind and large hail
will gradually expand east into southeast LA and southern MS through
the early morning hours. A tornado watch will be issued by around
05Z.

DISCUSSION...Late this evening a warm front extends from near the
Gulf Coast through southern LA. This boundary will move slowly north
through the early morning as the low-level jet strengthens in
response to a northeastward-ejecting shortwave trough. Northward
advection of richer low-level moisture and eastward expansion of
elevated mixed layer plume will destabilize the atmosphere
downstream from storms currently developing from southwest through
south-central LA. The destabilization process, increasing low-level
hodograph size and strong effective bulk shear will promote
supercells and bowing segments as storms continue east. Greatest
tornado threat may be as storms interact with warm front. Otherwise,
large hail and damaging wind will also be likely.

..Dial/Edwards.. 01/21/2017

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

ATTN...WFO...MOB...JAN...LIX...

LAT...LON   31798874 30848847 29678915 29258993 29359078 30159122
            30569154 31439162 32019022 31798874




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