Mesoscale Discussion 0188
NWS Storm Prediction Center Norman OK
0255 PM CDT Tue Mar 17 2020
Areas affected...Near/east of the Pecos River
Concerning...Severe potential...Watch possible
Valid 171955Z - 172230Z
Probability of Watch Issuance...60 percent
SUMMARY...Scattered strong to severe thunderstorm development seems
increasingly probable through the 5-7 PM CDT time frame. A severe
weather watch may be needed at some point.
DISCUSSION...One low-amplitude short wave impulse appears in the
process of progressing through broader-scale anticyclonic mid-level
flow across southwest and west Texas. As this continues, at least
weak mid-level cooling is expected to contribute to further
weakening of inhibition along a sharpening dryline, which is now
north and east of Wink and east of Fort Stockton.
In the presence of steep/steepening lapse rates, surface dew points
near and above 60F may already be contributing to mixed-layer CAPE
in excess of 1500 J/kg along the dryline, where strengthening of 500
mb flow to 40-50 kt during the past couple of hours has resulted in
increasingly favorable deep layer shear for supercells.
With some further destabilization possible as inhibition weakens,
model output generally suggests that discrete thunderstorm
development is possible by 22Z, before coverage gradually increases
with at least some upscale growth through 00Z. North of the higher
terrain near the Rio Grande River, this may commence near the
surface front, northwest through north of Midland, aided by forcing
for ascent associated with low-level warm advection, before
gradually developing southward along the dryline, near/east of the
Pecos River. Strongest storms probably will pose a risk for severe
hail and locally strong surface gusts.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 28680229 29250220 29710267 30440262 31070264 31640300
32220350 32510319 32500265 32110230 31660195 31320172
30040159 29320157 28270194 28130222 28680229