LIVE MAP (ABOVE) ... SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Thu Oct 01 2026
Valid 012000Z - 021200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHERN KANSAS/NORTHERN OKLAHOMA...
...SUMMARY...
Locally strong/gusty winds and perhaps a brief tornado or two may
occur this afternoon/early evening across parts of southern Kansas
into northwest Oklahoma and vicinity.
...20z Update...
Some trimming was done to the northwestern edge of the existing
Level 1/Marginal Risk area across southern Kansas where severe
probabilities have decreased in the wake of ongoing convection. See
MCD #2345 for additional short-term details.
Elsewhere, convective coverage has gradually increased over the past
hour across portions of south-central/south Texas amid hot and humid
conditions. A localized strong gust may occur with the strongest
downdrafts, but poor mid-level lapse rates and weakening deep-layer
flow/shear will limit overall convective intensity and preclude a
broader severe risk.
Recent HRRR/RRFS TLE data also suggest a low probability scenario
for an isolated stronger storm to develop along the surface frontal
boundary across northeastern Missouri/western Illinois later this
afternoon/evening. Poor mid-level lapse rates and limited available
buoyancy continue to suggest that the severity of any storm that can
develop is likely to remain muted, however.
..Chalmers/Thornton.. 10/01/2026
.PREV DISCUSSION... /ISSUED 1128 AM CDT Thu Oct 01 2026/
...Southern Kansas/Northern Oklahoma...
Recent surface analysis shows a weak low over northwest OK/the
northeast TX Panhandle, with a front extending northeastward from
this low across KS. A Pacific cold front also extends southward from
this low over the southern Plains. Cloud cover remains prevalent
over the warm sector across the southern/central Plains late this
morning, aided by lift associated with a mid/upper-level trough/low
centered over the southwest KS and the OK/TX Panhandles per latest
water vapor satellite imagery. While not a classic setup for
non-supercell tornadoes given modest low-level lapse rates and a
progressive cold front, there may still be a window for a brief
tornado or two this afternoon/early evening across parts of southern
KS into northwest OK and vicinity.
This area should generally warm into the 70s per recent RAP/HRRR
guidance, and even modest breaks in the cloud cover should support
some steepening of low-level lapse rates in an otherwise
vorticity-rich environment along/near both fronts. Current
expectations are for cells to develop over southwest KS/northwest OK
in the next couple of hours (by 18-20Z), with cool temperatures
aloft (around -10 to -11 C at 500 mb) aiding updraft strength in an
otherwise weak deep-layer shear environment. Small hail, strong to
locally severe winds, and perhaps a brief tornado could occur with
this activity until the southeastward-advancing cold front undercuts
convection by late afternoon/early evening.
...Texas/ArkLaTex into the Mid Mississippi Valley/Midwest...
Ongoing convection across central/north-central TX has remained
sub-severe through the morning. A rather moist low-level airmass
characterized by generally mid to upper 70s surface dewpoints is
present across east/coastal TX ahead of these thunderstorms. While
lapse rates aloft will remain poor (reference 12Z observed soundings
from FWD/DRT), some increase in instability is anticipated
downstream this afternoon with continued daytime heating.
South-southwesterly low/mid-level flow will continue to gradually
diminish through the day as the primary mid/upper-level trough
ejects northeastward across the southern/central Plains through this
evening. This will limit the degree of deep-layer shear available to
support organized updrafts and overall severe potential across the
ArkLaTex into east/south TX. That said, gusty winds may still occur
on a localized basis as convection spreads eastward across these
areas through the afternoon/evening.
Modestly enhanced mid-level flow and greater deep-layer shear will
be present this afternoon farther north into the mid MS
Valley/Midwest, as multiple subtle mid-level vorticity maxima spread
northeastward over these regions. However, both boundary-layer
instability and lapse rates aloft are forecast to remain rather
weak, which should limit updraft strength and overall severe
potential with northward extent across these areas.
Read more CHECK UPDATE ZOOM GRAPHIC
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