SPC Mesoscale Discussion
SPC MD 488
MD 0488 CONCERNING SEVERE THUNDERSTORM WATCH 147... FOR PORTIONS OF SOUTHWESTERN INTO CENTRAL TEXAS
Mesoscale Discussion 0488
NWS Storm Prediction Center Norman OK
0711 PM CDT Sat Apr 19 2025
Areas affected...portions of southwestern into central Texas
Concerning...Severe Thunderstorm Watch 147...
Valid 200011Z - 200145Z
The severe weather threat for Severe Thunderstorm Watch 147
continues.
SUMMARY...The severe threat continues across Severe Thunderstorm
Watch 147 and Tornado Watch 148. Severe hail appears to be the main
threat in the short term, though a couple of tornadoes cannot be
ruled out, particularly in Tornado Watch 148.
DISCUSSION...Several supercells are training along a baroclinic
boundary across southwestern into central TX, with a history of
producing severe hail up to 2 inches in diameter, as also shown by
recent MRMS mosaic radar data. Ample buoyancy (e.g. 1500-2000 J/kg
MUCAPE) amid strong deep-layer shear should continue to support
severe hail with these storms over the next few hours. Many of these
storms appear to be undercut by a southward-sagging baroclinic
boundary, which has succeeded at impeding adequate surface-based
inflow for better tornado potential so far. However, with time,
these storms are expected to pivot eastward into the warm-sector,
where a preceding southerly low-level jet continues to intensify.
Regional VADs across central into northern TX also show low-level
hodographs becoming larger and more curved. As such, a couple of
tornadoes remain possible with any storms that manage to cross the
baroclinic boundary into the warm sector.
Later this evening, storms may eventually merge into one or more
MCSs, perhaps progressing eastward as LEWPs with a damaging
gust/isolated tornado threat, as suggested by some of the latest
high-resolution guidance.
..Squitieri.. 04/20/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FWD...OUN...SJT...MAF...
LAT...LON 30990255 32689985 33519857 33569805 33279791 32459807
31569836 31159903 30940066 30990255
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
Read more
SPC MD 487
MD 0487 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PORTIONS OF NORTHERN TEXAS INTO SOUTHERN OKLAHOMA
Mesoscale Discussion 0487
NWS Storm Prediction Center Norman OK
0629 PM CDT Sat Apr 19 2025
Areas affected...portions of northern Texas into southern Oklahoma
Concerning...Severe potential...Watch likely
Valid 192329Z - 200100Z
Probability of Watch Issuance...80 percent
SUMMARY...The severe threat is increasing over northern Texas into
southern Oklahoma. All severe hazards are possible, though tornado
potential is largely dependent on efficient surface-based inflow. A
WW issuance is likely.
DISCUSSION...Increasing WAA and low-level southerly flow is underway
over the Red River vicinity, with the intensity and coverage of
storms also increasing with the approach of a 500 mb jet streak. A
supercell structure has recently intensified and produced a tornado
along a baroclinic boundary in Jack County, TX, and this storm
(along with others that can intensify) are preceded by the terminus
of a 30+ kt southerly 850 mb jet. In addition to increasing buoyancy
downstream of these storms, low-level shear is also increasing, with
the FWS VAD depicting modestly curved and elongated hodographs. Any
storms that can mature and progress in this environment will be
capable of producing severe hail/wind. Additional tornadoes may also
be possible if storms can remain surface-based, and maintain
relatively unimpeded inflow.
Given the increasing severe threat, a WW issuance may be needed
soon.
..Squitieri/Smith.. 04/19/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TSA...FWD...OUN...
LAT...LON 33059786 33679790 34429772 34829706 34899629 34709569
34069537 33409553 32909601 32549669 32369716 32309785
32689796 33059786
MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
Read more
