Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 222002
SWOMCD
SPC MCD 222002
GAZ000-FLZ000-222100-

Mesoscale Discussion 0117
NWS Storm Prediction Center Norman OK
0202 PM CST Sun Jan 22 2017

Areas affected...Portions of north FL and south GA

Concerning...Tornado Watch 21...

Valid 222002Z - 222100Z

The severe weather threat for Tornado Watch 21 continues.

SUMMARY...The onset of a dangerous tornado outbreak is ongoing. A
line of potentially tornadic supercells is spreading eastward around
45-50 kt. Long-track, fast-moving, strong tornadoes will be
possible.

DISCUSSION...A line of discrete/semi-discrete supercells extending
from far southwest GA to central/eastern portions of the FL
Panhandle will continue spreading eastward around 45-50 kt.
Approximate times of arrival of this line are depicted in the
accompanying graphical product. Storm-relative motion from radar
suggests tightening/strengthening low-level mesocyclones with this
activity. This activity now lies east of a front that arcs northward
to surface low pressure over central AL featuring a deepening rate
of over 1 mb per hour. Preceding pressure falls of 7-9 mb per 2
hours have been noted, with open-warm-sector pressure falls of 3-6
mb per 2 hours. As a plume of high theta-e air continues to stream
northward to a warm front advancing north across south GA (serving
as convective inflow), and very strong low-level SRH (around 550
m2/s2 in the lowest 1 km above ground per Tallahassee VAD wind
profile) continues given the strong surface cyclogenesis, the
potential for significant, long-track, fast-moving tornadoes will
exist.

..Cohen.. 01/22/2017

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

ATTN...WFO...JAX...FFC...TAE...

LAT...LON   31558464 32018406 31958312 31148294 29988310 29708361
            29668433 30018477 31558464



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