Mesoscale Discussion 0574
NWS Storm Prediction Center Norman OK
0255 PM CDT Sun Apr 27 2025
Areas affected...,parts of swrn TX
Concerning...Severe potential...Watch possible
Valid 271955Z - 272100Z
Probability of Watch Issuance...40 percent
SUMMARY...The initiation of a couple of storms appears increasingly
likely near and northwest through north of Fort Stockton through 4-5
PM CDT. More rapid thunderstorm intensification accompanied by
increasing potential for large hail and locally damaging wind gusts
may be initially slow, before probably increasing toward early
evening around the Midland through Big Spring vicinities.
DISCUSSION...The boundary-layer is becoming strongly heated and
deeply mixed across the Davis Mountains vicinity of southwest Texas
into the Texas South Plains. The dryline is sharpening east through
north of Fort Stockton, where 2-hourly surface pressure falls around
2.0+ mb have been observed the past couple of hours, and low-level
convergence appears strongest.
Deepening convective development is ongoing within the deeper
mixed-boundary layer around Fort Stockton, where surface
temperature/dew point spreads are around 50 F (95/44), but forecast
soundings and HREF guidance suggests that the initiation of at least
isolated thunderstorm development is increasingly probable through
21-22Z. It appears that this may be aided by forcing associated
with a mid-level speed maximum within southwesterly flow emanating
from the northern Mexican Plateau.
Downstream of slow moving large-scale mid-level troughing over the
southern Great Basin and Southwest, after at least some further
eastward mixing of the dryline late this afternoon, it probably will
begin to retreat northwest across the Pecos Valley vicinity toward
23-00Z. As this occurs, convection may acquire more substantively
unstable updraft inflow (including most unstable CAPE up to
2000-3000+ J/kg), supporting increasing potential for rapid
thunderstorm intensification, in the presence of strong deep-layer
shear. This may including a splitting supercell or two, posing a
risk for large hail and a few strong surface gusts.
Until then, though, initial thunderstorm development will probably
be more modest in strength, but could still pose some risk for
producing severe hail and wind.
..Kerr/Smith.. 04/27/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SJT...LUB...MAF...
LAT...LON 30410326 30870341 31970321 32930244 33180156 32510109
32000117 31040164 30280230 30410326
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
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