Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS11 KWNS 232033
SPC MCD 232032
Mesoscale Discussion 0311
NWS Storm Prediction Center Norman OK
0332 PM CDT Thu Mar 23 2017
Areas affected...Portions of the Southern/Central High Plains
Concerning...Severe potential...Watch likely
Valid 232032Z - 232130Z
Probability of Watch Issuance...95 percent
SUMMARY...Thunderstorms should organize across portions of the Texas
Panhandle late this afternoon into early evening, before spreading
north/northeast. A threat for damaging winds and large hail will
exist with the strongest cells. Watch issuance is expected soon.
DISCUSSION...Surface observations across the TX/OK panhandles
indicate that surface moisture has mixed out significantly, with
most locations reporting dew points in the 40s and lower 50s.
Nonetheless, ample insolation and steep low/mid-level lapse rates
have yielded MLCAPE values upwards of 1000 J/kg in spots.
Additionally, northward advection of greater moisture to the south
may encourage MLCAPE upwards of 1500 J/kg this evening.
Satellite and regional radar data suggest large-scale ascent is
starting to reach the southern High Plains late this afternoon, with
high-based showers organizing over the eastern New Mexico plains. As
this ascent translates eastward, inhibition should weaken
sufficiently such that overall convective intensity increases as
cells reach greater moisture across the Texas Panhandle. KAMA VWP
and mesoanalysis data suggest around 40-50 kts of effective shear is
available for updraft organization. Combined with steep mid-level
lapse rates, this kinematic profile will support large-hail growth
in robust, sustained convection. Additionally, a well mixed, dry
profile (resulting in DCAPE of 1000-1400 J/kg) and vigorous,
somewhat unidirectional flow will favor damaging wind gusts. As
such, watch issuance is expected soon. Over time this evening, the
severe threat will spread northeast, as storms evolve into southwest
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 34220092 33530132 33410241 33550298 33980300 35470278
36500245 38030188 38160158 38170068 37930014 36989999