RSS Mesoscale Discussions from Storm Prediction Center
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Fri May 22 2026
Valid 221200Z - 231200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN HIGH PLAINS...
...SUMMARY...
Thunderstorms with large hail and severe wind gusts will be possible
from late this afternoon into the evening in parts of the southern
High Plains. Isolated severe gusts and hail may occur in parts of
the mid Missouri Valley. A few severe gusts and a marginal tornado
threat will also be possible from the central Gulf Coast States into
the Tennessee and southern Ohio Valleys.
...Southern High Plains...
A mid-level shortwave trough will move eastward into the southern
High Plains today. Ahead of the trough, a moist and unstable airmass
will be located across most of Texas and Oklahoma. Thunderstorms are
expected to develop late this afternoon on the moisture gradient
from the western Texas Panhandle southward into west Texas. These
storms will move eastward across the southern High Plains during the
late afternoon and evening.
The strongest instability is forecast to develop this afternoon over
the low Rolling Plains of northwest Texas, where model forecasts
have MLCAPE peaking in the 2000 to 3000 J/kg range. Late afternoon
forecast soundings in northwest Texas have 0-6 km shear around 30
knots with 700-500 mb lapse rates near 8 C/km. This environment will
support the development of supercells with large hail and severe
wind gusts. Hailstones greater than 2 inches in diameter will be
possible with supercells that become dominant. The greatest severe
threat is expected to be in the evening as a broken line of storms
moves into the stronger instability from the eastern Texas Panhandle
southward into northwest Texas.
...Mid Missouri Valley...
An upper-level trough and an associated mid-level jet streak will
move northeastward today across the north-central U.S. At the
surface, an axis of low-level moisture will be in place from eastern
Kansas northward into eastern Nebraska. Ahead of the trough,
scattered thunderstorms will develop in the afternoon along and near
the moist axis. Surface dewpoints in the lower to mid 60s F will
contribute to weak instability with MLCAPE likely peaking in the 500
to 1000 J/kg range across eastern Nebraska. RAP forecast soundings
near Omaha suggest that 0-6 km shear will reach 35 knots as the
trough approaches this afternoon, which would support the
development of low-topped supercells capable of isolated severe wind
gusts and hail. The severe threat is expected to persist into the
early evening.
...Central Gulf Coast States/Ohio and Tennessee Valleys...
A negatively-tilted mid-level shortwave trough will move
northeastward today across the east-central U.S. Ahead of the
trough, low-level moisture advection will take place. By early
afternoon, surface dewpoints will be from the mid 60s to lower 70s F
from the central Gulf Coast states northward into the southern Ohio
Valley. Moderate instability is expected by afternoon across much of
the region with MLCAPE peaking between 1500 and 2500 J/kg. Locally
stronger instability is expected across central Mississippi,
east-central Kentucky, eastern Tennessee and northeast Georgia. As
surface temperatures warm during the day, scattered thunderstorms
will develop and move northeastward across the moist airmass.
Steepening low-level lapse rates will support a potential for
isolated severe wind gusts. In addition, hodographs across this
unstable airmass are forecast to be somewhat curved, which should
also support a marginal tornado threat.
..Broyles/Chalmers.. 05/22/2026
Read more
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1258 AM CDT Fri May 22 2026
Valid 231200Z - 241200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE SOUTHERN PLAINS AND SOUTHEAST...
...SUMMARY...
Scattered strong to potentially severe storms appear possible from
the Raton Mesa vicinity into the Oklahoma and Texas Panhandles and
southward near the middle Texas Coast. Additional severe
thunderstorms will be possible in portions of central Georgia.
...Synopsis...
A weak impulse will rotate across the central Plains on D2/Saturday
as a surface low moves northward across the Ohio Valley. A trailing
cold front will extend from the surface low back into the southern
Plains. Widely scattered thunderstorm activity will be possible
from the central/southern Plains into the lower Mississippi Valley
and across the Southeast. A few stronger storms may be possible
across portions of the southern Plains and the southeastern US.
...TX/OK Panhandles...
Weak forcing for ascent and easterly upslope flow across the Caprock
and into the higher terrain in eastern New Mexico will produce
scattered thunderstorm activity Saturday afternoon. These are
progged to move eastward downstream across the Panhandles into
portions of western Oklahoma. Forecast soundings suggest a plume of
steep to low mid-level lapse rates will still reside across the
OK/TX Panhandles with mid 50s to 60s dew points and moderate
instability. Shear profiles will be marginal, with deep layer shear
around 25-30 kts. Nonetheless, a few more organized storms may
produce strong to severe wind and instances of severe hail.
...Middle Texas Coast...
Thunderstorm activity is expected to form near the Edwards Plateau
on Saturday afternoon and move south and east towards the middle
Texas coast. Ahead of this, moderate to strong afternoon instability
and steep low to mid-level lapse rates will be in place across
portions of southern Texas. Some enhancement of
deep-layer shear is forecast across south TX, which will may provide
opportunity for cold pool organization and damaging wind.
...Central/Southern Georgia...
A weak shortwave will move across Georgia Saturday afternoon as
widely scattered thunderstorm development occurs. Most guidance
suggests deep layer shear around 30-40 kts which may allow for a few
more organized cells. These may produce a few instances of strong to
severe wind.
..Thornton.. 05/22/2026
Read more
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 AM CDT Fri May 22 2026
Valid 241200Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF
EASTERN NEBRASKA INTO EASTERN IOWA...
...SUMMARY...
Widely scattered thunderstorm activity will be possible from the
southern/central Plains to the southeastern US into the lower Ohio
Valley. A few stronger storms may be possible across portions of the
Nebraska and Iowa.
...Synopsis...
Widely scattered afternoon thunderstorms are likely south of a
stationary front extending from the southern Plains into the lower
Ohio Valley. A few additional thunderstorms will be possible across
the southern High Plains within the easterly upslope regime. A
shortwave trough will move across the central/northern Plains into
the Upper Midwest on D3/Sunday, which may be a focus of thunderstorm
development across portions of Nebraska and Iowa. A few stronger
thunderstorms may be possible in these regions.
...Eastern Nebraska, southeastern South Dakota, western Iowa...
As the shortwave moves through the central Plains, guidance has
trended northward with moisture return into the central Plains by
D3/Sunday. Some deterministic guidance (NAM, ECMWF, GFS) suggest
that a plume of mid 50 to 60s dew points may advect up into eastern
Nebraska near a northward moving pseudo warm frontal boundary. A
narrow corridor of moderate instability may develop and overlap
around 40-45 kts of deep layer shear across this region by Sunday
afternoon. Forecast soundings depict supercells profiles, with steep
low to mid-level lapse rates. While there remains some low
confidence in moisture availability, trends in 00z guidance suggest
adding in low end severe probabilities.
...Southeast...
A few stronger thunderstorms may develop across portions of the
southeastern US Sunday afternoon. Though shear profiles are
generally weak, moderate instability will be in place with strong
daytime heating and potential for water laden down bursts and a few
instances of strong to locally severe wind.
..Thornton.. 05/22/2026
Read more
