Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS11 KWNS 222002
SPC MCD 222002
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
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
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 31558464 32018406 31958312 31148294 29988310 29708361
29668433 30018477 31558464