RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sat May 30 13:45:02 UTC 2026.
No Mesoscale Discussions are in effect as of Sat May 30 13:45:02 UTC 2026.
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0725 AM CDT Sat May 30 2026
Valid 301300Z - 311200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
HIGH PLAINS INTO CENTRAL KANSAS AND NORTH-CENTRAL OKLAHOMA...
...SUMMARY...
Scattered severe thunderstorms are possible this afternoon and
evening over the central Great Plains. The stronger thunderstorms
will potentially be capable of large to very large hail, severe
gusts, and perhaps a couple of tornadoes.
...NE Panhandle into the northern High Plains...
A mid-level trough along the UT/CO border will migrate slowly
northeast with a belt of 20-40 kt cyclonic 500-mb flow wrapping
cyclonically through the base of the trough into the NE Panhandle
and Black Hills. In the low levels, an elongated area of surface
low pressure/lee trough will focus thunderstorm development later
this afternoon/evening. The western part of a moisture plume
extending from the southern Great Plains northward into western
NE/SD will feature 50s to lower 60 F dewpoints. Strong heating and
large-scale ascent will combine to weaken the capping inversion and
result in widely scattered thunderstorms developing by mid-late
afternoon. Slightly stronger deep-layer shear across NE will favor
a mix of supercells and multicells with the stronger storms. Large
hail and severe gusts will be possible with the stronger
thunderstorms through the mid evening as this activity probably
grows upscale into a linear cluster or two.
...NE-KS and into OK-TX...
Models continue to show a sharp dryline across western/central
KS, western OK, and into west TX by late afternoon. Main lobe of
forcing for ascent associated with the upper trough will likely
glance the northwestern quadrant of KS into NE. Surface
mesoanalysis this morning shows a low over northeast CO near AKO and
an effective outflow boundary draped east along I-70 in
north-central KS. North of the boundary, easterly surface winds
will contribute to maintaining moist upslope flow.
Ample heating in wake of early morning convection and an
increasingly rich moisture plume arcing from north-central OK into
southwest NE, will favor a very unstable airmass developing by
mid-late afternoon (3500-4500 J/kg MLCAPE). Some forecast
uncertainty remains regarding low-level hodographs due to model
spread (e.g., RAP and HRRR time-lagged depictions favoring more
supercells vs. NAM with less favorable hodographs and indicative of
more multicellular structures). Furthermore, effective shear is
forecast to be only 25-35 knots and will likely straddle the
multicell-supercell spectrum. Where slightly stronger shear and
some enlargement of clockwise-curved hodographs are currently
expected, it is where supercells are more probable and the risk for
large to very large hail and a couple of tornadoes are increasingly
possible. Have opted to include a 5-percent tornado risk over
north-central KS into southwest NE, with this region being located
north of this morning's west-east boundary and in closer proximity
to the upper wave. Farther south, lower storm coverage (isolated)
is expected into OK and more sparse and widely spaced activity
farther south along the dryline in parts of west TX. Large hail and
severe gusts are the primary hazards with these storms.
...Southwest Missouri into central Arkansas...
A zone of isentropic ascent near 850 mb will become established
across the Ozark Plateau by late afternoon. Isolated to scattered
thunderstorms are likely within this corridor. Models show large
SBCAPE (3000 J/kg) and adequate deep-layer shear for some storm
organization. A few stronger cells may be capable of large hail and
perhaps strong/severe wind gusts.
..Smith/Kerr.. 05/30/2026
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