SPC MD 1340

MD 1340 CONCERNING SEVERE THUNDERSTORM WATCH 430... FOR PARTS OF THE ROLLING PLAINS

Mesoscale Discussion 1340
NWS Storm Prediction Center Norman OK
0848 PM CDT Tue Jun 17 2025

Areas affected...Parts of the Rolling Plains

Concerning...Severe Thunderstorm Watch 430...

Valid 180148Z - 180315Z

The severe weather threat for Severe Thunderstorm Watch 430
continues.

SUMMARY...The risk of severe wind gusts and sporadic large hail
continues across the Rolling Plains.

DISCUSSION...A pair of organized thunderstorm clusters (with
occasional supercellular structures) continue tracking slowly
east-southeastward across the Rolling Plains. These storms have a
history of producing severe wind gusts (measured 68 mph) and
marginally severe hail. The MAF 00Z sounding (which should be
generally representative of the near-storm environment) sampled
steep deep-layer lapse rates, while the LBB VWP depicts a
long/straight hodograph (around 45 kt of 0-6 km shear). This should
support the maintenance of the ongoing storms, with a continued risk
of severe wind gusts and sporadic large hail. 

While these storms will have a tendency of tracking southeastward
out of Severe Thunderstorm Watch 430 with time, current thinking is
that increased inhibition at the base of the EML will eventually
lead to weakening with southeastward extent. Therefore, a new watch
is not currently expected, though convective trends are being
monitored.

..Weinman.. 06/18/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...OUN...SJT...LUB...MAF...

LAT...LON   33330203 34200104 34340066 34310022 34059984 33649981
            33130021 32610122 32710175 32950199 33330203 

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN

SPC MD 1339

MD 1339 CONCERNING TORNADO WATCH 429... FOR PARTS OF SOUTHERN KS...NORTHERN OK...FAR SOUTHWEST MO...AND FAR NORTHWEST AR

Mesoscale Discussion 1339
NWS Storm Prediction Center Norman OK
0813 PM CDT Tue Jun 17 2025

Areas affected...Parts of southern KS...northern OK...far southwest
MO...and far northwest AR

Concerning...Tornado Watch 429...

Valid 180113Z - 180315Z

The severe weather threat for Tornado Watch 429 continues.

SUMMARY...A general increase in thunderstorm coverage is expected
across the area during the next several hours. One or more MCSs may
evolve out of this activity, posing a risk of scattered severe wind
gusts. A new watch will likely be issued before 03Z to replace
Tornado Watch 429.

DISCUSSION...A persistent upscale-growing supercell cluster
continues tracking east-southeastward along the KS/OK border --
along the immediate cool side of a large-scale outflow boundary
extending across northern OK. These storms should continue moving
along a related east/west-oriented instability gradient, where
around 60 kt of 0-6 km shear (per nearby VWP) and ample low-level
hodograph curvature will continue to support large hail, severe wind
gusts, and possibly an embedded tornado. Farther west, an intense
semi-discrete supercell is moving southeastward over far northwest
OK and the northeastern TX Panhandle. Very strong surface-based
instability and a large clockwise-curved hodograph (around 300 m2/s2
effective SRH) will continue to favor a risk of tornadoes (some
possibly strong) and large hail in the near-term. 

Over the next several hours, a general increase in thunderstorm
coverage is expected along outflow boundaries, as a midlevel wave
(evident in water-vapor imagery) moves into the region. While
overall convective evolution is uncertain, a strongly unstable air
mass remains in place along/south of the large-scale outflow
boundary in northern OK/southern KS (see OUN 00Z sounding). This,
combined with the increasing large-scale ascent and a focused
low-level jet, should support the development of one or more
organized MCSs -- capable of producing scattered severe wind gusts.
A new watch will likely be issued prior to the expiration of Tornado
Watch 429 at 03Z.

..Weinman/Mosier.. 06/18/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...SGF...TSA...TOP...ICT...OUN...DDC...AMA...

LAT...LON   35389951 35570005 35890028 36310030 36810019 37549949
            37789888 38089768 38159659 37979525 37549427 37009392
            36499412 36089458 35699528 35459663 35389951 

MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
MOST PROBABLE PEAK WIND GUST...75-90 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN