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Categorical Day2 1730Z Outlook
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Images courtesy of the NWS Storm Prediction Center
Open the discussion at the Storm Prediction Center
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1132 AM CST Sun Nov 01 2026
Valid 021200Z - 031200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NORTH
TEXAS...OKLAHOMA AND INTO KANSAS AND MISSOURI...
...SUMMARY...
Scattered severe storms are expected across parts of the central and
southern Plains late Monday afternoon into the evening, with
damaging wind gusts and a few tornadoes the main threats.
...Synopsis...
A deep but initially disorganized upper trough over the Southwest is
forecast to amplify considerably as several subtropical and polar
stream disturbances coalesce Monday into Monday night. An 80+ kt
subtropical speed max, and an associated shortwave trough, will
rapidly move northeastward from eastern NM and CO to the Missouri
Valley by Monday evening. Strong ascent will deepen a lee low below
1000 mb across NE/SD, with a trailing cold front that will move into
western NE and KS before surging eastward overnight. A dryline and
lee trough will extend roughly from central KS into western OK and
west-central TX aided by a secondary shortwave trough moving from
the Four Corners into TX and western OK. As this feature gradually
becomes neutral/negatively tilted, robust height falls (12-15
DAM/12hrs) will overspread the Plains sustaining a 50-60 kt
low-level jet aiding northward advection of widespread mid 60s F
surface dewpoints.
...TX/OK/KS...
In the wake of a round of morning storms associated with the passing
subtropical shortwave, a narrow corridor of robust surface heating
should allow surface temperatures to warm into the mid/upper 70s F
immediately ahead of the dryline from the TX Panhandle into
southwest KS and western OK. This should allow for scattered
thunderstorm development and maturation with MLCAPE of 1000-1500
J/kg late Monday afternoon. 60-80 kt mid-level flow overspreading
the dryline will support robust deep-layer shear profiles (effective
shear 45-60 kt) favorable for organized severe storms. A narrow zone
of semi-discrete supercell potential is evident near the dryline
late in the day, with some hail, a few tornadoes and damaging wind
possible. Despite the strong shear, the impact of a mixed convective
mode and uncertainty on diurnal destabilization across the broader
warm sector remains unclear.
AIFS ensemble guidance continues to show a secondary low center
developing and intensifying beneath the maximum in height falls
aloft near the KS/OK border Monday evening. The moist and
semi-stratified air mass, along with strong isallobaric flow will
support very strong low-level shear with model hodographs showing
0-1km SRH of 300-500 m2/s2. While convective mode is likely to
transition to a more linear arrangement as forcing increases,
embedded supercellular elements and QLCS circulations will likely
persist given the robust shear environment. A few tornadoes (some
possibly strong) and severe gusts are possible near the track of the
meso low along the KS/OK border into the evening and early overnight
hours.
...Eastern KS/MO into NE/IA...
Farther north and east, instability is forecast to be limited with
residual cloud cover and continuous low-level warm advection
expected to temper heating. Still, cooling mid-level temperatures
and strong forcing for ascent should be adequate for at least weak
destabilization amid 60s F surface dewpoints. Very strong low-level
shear will be in place much of the day near and south of the
deepening surface low. This should continually strengthening through
the evening as the upper trough intensifies. Despite the minimal
buoyancy, pre-frontal warm air advection storms are possible before
consolidation ahead of the surging cold front favors a low-topped
narrow QLCS. Poor lapse rates in the low-levels cast uncertainty on
the damaging wind potential, but the strong shear and mesovorticies
could support a few strong gusts and brief tornadoes into the
overnight hours.
..Lyons.. 11/01/2026
