MD 1699 CONCERNING SEVERE THUNDERSTORM WATCH 508... FOR KENTUCKY INTO NORTHERN TENNESSEE AND FAR WESTERN VIRGINIA
Mesoscale Discussion 1699
NWS Storm Prediction Center Norman OK
0448 PM CDT Tue Jul 21 2026
Areas affected...Kentucky into northern Tennessee and far western
Virginia
Concerning...Severe Thunderstorm Watch 508...
Valid 212148Z - 212345Z
The severe weather threat for Severe Thunderstorm Watch 508
continues.
SUMMARY...The potential for damaging winds, large hail, and perhaps
a tornado or two is expected to spread south of the watch area
between 23Z and 00Z. A new watch will be required prior to that
time.
DISCUSSION...Regional radar imagery shows a mix of supercells and
bowing structures ongoing across eastern and central parts of the
watch area with more recent storm development present near the
confluence of the Mississippi and Ohio Rivers. The inflow air mass
to the storms is warm and quite moist with MLCAPE of 2500-3500+
J/kg, per recent objective analysis. However, considerable downshear
anvil blowoff has limited the potential for stronger insolation
across the warm sector, which in turn is resulting in relatively
poor low-level lapse rates. Kinematically, regional VWPs are
sampling seasonably strong mid- and high-level winds and resultant
deep-layer shear with the strongest low-level shear currently
analyzed from eastern KY into western WV.
Extrapolation of current storm motions takes the storms to the
southern edge of the watch area between 23Z and 00Z with latest CAM
guidance suggesting the storms will remain intense as they continue
into portions of TN and far western VA. That scenario appears
reasonable given the presence of the strong vertical shear. Expect
the continuation of supercell and bowing structures with the primary
hazards being damaging winds and large hail. The extent of the
longer-term tornado threat remains somewhat uncertain owing to the
weaker low-level lapse rates, which may limit near-ground parcel
accelerations. However, in the near-term, the greatest tornado risk
will extend from the tornadic supercell in Hart County KY, into
eastern KY where low-level shear is the strongest.
..Mead.. 07/21/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...RLX...MRX...JKL...ILN...LMK...OHX...PAH...MEG...
LAT...LON 36228986 36678976 37848656 38748303 38308240 37598192
36858211 36248375 35928569 36118836 36218938 36228986
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
MD 1698 CONCERNING TORNADO WATCH 507... FOR PARTS OF SOUTHERN NJ
Mesoscale Discussion 1698
NWS Storm Prediction Center Norman OK
0442 PM CDT Tue Jul 21 2026
Areas affected...Parts of southern NJ
Concerning...Tornado Watch 507...
Valid 212142Z - 212315Z
The severe weather threat for Tornado Watch 507 continues.
SUMMARY...A locally favorable corridor for damaging wind gusts is
evident in southern New Jersey for the next hour or two -- within
Tornado Watch 507.
DISCUSSION...Clusters of thunderstorms are tracking eastward across
far southwestern NJ, with some low/midlevel rotation evident in the
last 15 minutes or so. These storms are moving into a corridor of
strong heating/destabilization of a very moist PBL (upper 70s
dewpoints). This, combined with a long/mostly straight hodograph
(around 50 kt of 0-6 km shear per DIX VWP), will favor a continued
risk of organized clusters capable of producing damaging wind gusts
as they track eastward across southern NJ during the next hour or
two. While low-level shear is not particularly strong, the ample PBL
moisture could support a brief tornado with any embedded
mesovortex/supercell structures.
..Weinman.. 07/21/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PHI...
LAT...LON 39647539 40107480 40197446 40127406 39967394 39217434
38867476 38907514 39357554 39647539
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
MD 1697 CONCERNING SEVERE THUNDERSTORM WATCH 509... FOR EASTERN VIRGINIA INTO THE DELMARVA
Mesoscale Discussion 1697
NWS Storm Prediction Center Norman OK
0343 PM CDT Tue Jul 21 2026
Areas affected...eastern Virginia into the DelMarVa
Concerning...Severe Thunderstorm Watch 509...
Valid 212043Z - 212215Z
The severe weather threat for Severe Thunderstorm Watch 509
continues.
SUMMARY...The severe weather threat will continue through the
afternoon and into the evening.
DISCUSSION...Storms across Virginia and into the DelMarVa have
mostly lacked structure thus far with only occasional stronger
multi-cell storms. As height falls overspread the area this evening,
expect more robust convection with a greater damaging wind threat
and an eventual line of storms along or ahead of the cold front,
advances east. In addition, strengthening mid-level and low-level
flow will assist in storm organization, further supporting the
threat.
..Bentley.. 07/21/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...PHI...AKQ...LWX...RNK...
LAT...LON 36648039 37457909 38317774 38907701 39477640 39497553
39107487 38507479 37967507 37297548 36677596 36648039
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
MD 1696 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE EASTERN GREAT BASIN
Mesoscale Discussion 1696
NWS Storm Prediction Center Norman OK
0323 PM CDT Tue Jul 21 2026
Areas affected...portions of the eastern Great Basin
Concerning...Severe potential...Watch unlikely
Valid 212023Z - 212230Z
Probability of Watch Issuance...5 percent
SUMMARY...Scattered, high-based thunderstorms are expected this
afternoon and evening across much of the Great Basin. Isolated
damaging/severe wind gusts may occur with the strongest downdrafts.
DISCUSSION...18z observed soundings from GJT/SLC depicted dry,
increasingly well-mixed boundary layer profiles underlying steep
mid-level lapse rates. Amid enhanced mid-level moisture and ahead of
a weak mid-level perturbation along the western periphery of an
upper-level ridge, convective coverage is forecast to increase
through the afternoon as convective temperatures are breached.
Inverted-v thermodynamic profiles with LCLs of 2.5-3.0+ km will
promote efficient evaporative cooling and the potential for isolated
damaging/severe wind gusts with downdrafts. The best potential for
this risk may manifest from southeastern Utah/far western Colorado
into central Utah where marginally stronger low-to-mid level flow
(20-25 kts sampled by the GJX/ICX VWPs) and effective shear (20-25
kts per latest objective analysis) may promote a loosely organized
convective cluster or two. The threat for damaging/severe wind gusts
is forecast to remain too isolated to warrant watch issuance at this
time, however.
..Chalmers/Mosier.. 07/21/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GJT...SLC...LKN...
LAT...LON 37651219 38241325 39261416 40481446 41131416 41611339
41561219 41111100 40631010 40130941 39460876 38790857
37900872 37250932 37091006 37111048 37251135 37651219
MOST PROBABLE PEAK WIND GUST...55-70 MPH
Read more