Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS11 KWNS 220440
SPC MCD 220439
Mesoscale Discussion 0543
NWS Storm Prediction Center Norman OK
1139 PM CDT Fri Apr 21 2017
Areas affected...Portions of extreme southeast Oklahoma...North
Texas...southwest Arkansas and northwest Louisiana
Concerning...Tornado Watch 155...
Valid 220439Z - 220615Z
The severe weather threat for Tornado Watch 155 continues.
SUMMARY...An increasingly isolated risk for mainly large hail will
continue through the scheduled 06Z expiration for the watch. It
remains unclear whether a replacement severe thunderstorm watch will
be needed, and trends will continue to be monitored.
DISCUSSION...Several severe thunderstorms remain across the watch
area as of 0430Z, primarily from southwest AR into north-central TX.
Most of the strong/severe storms are elevated in nature just behind
a cold front that continues to move steadily southeast across north
Texas. An isolated severe storm near or slightly in advance of the
front was located over Sevier and Little River counties in AR.
Weak-moderate elevated buoyancy remains across eastern portions of
the watch area and effective shear values of 45-50 kts will continue
to support organized updrafts with a risk primarily for large hail.
Currently, based on the latest high-resolution guidance it appears
that some continued severe risk will exist after the scheduled 06Z
expiration of the watch. It remains unclear whether the threat will
become sufficiently isolated to allow the watch to expire, or that a
new severe thunderstorm watch would be needed over the ARKLATEX
region. Convective trends will continue to be monitored.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 35099407 35069353 34789308 34189238 33349240 32749309
32409479 32129564 31949657 31849707 31759754 31729804
32019822 32339835 32689830 33279773 34329494 35099407