SPC Sep 30, 2026 0600 UTC Day 1 Convective Outlook
SPC 1200Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Wed Sep 30 2026

Valid 301200Z - 011200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHWEST
OK/NORTHWEST TX INTO THE EDWARDS PLATEAU...

...SUMMARY...
Thunderstorms capable of severe wind gusts and possibly a brief
tornado appear possible across portions of the southern Plains this
afternoon into tonight. A conditional risk for isolated severe wind
gusts and perhaps a couple tornadoes exists over parts of Kansas and
southern Nebraska this afternoon and evening.

...Central/southern Plains...
A mid/upper-level low will move from the southern Rockies toward the
central High Plains through the period. A surface low initially over
the southern High Plains is forecast to move only slowly eastward
into tonight. A warm front extending northeast of the surface low
may move slowly northward through the day, though persistent clouds
and precipitation may slow its advance.

A rather strong low-level jet is forecast to slowly shift
northeastward across parts of central/eastern KS into western MO and
southeast NE/southwest IA later today into the evening. This will
help to maintain favorable wind profiles in the vicinity of the
effective warm front. Destabilization near the warm front may remain
weak due to limited diurnal heating and weak midlevel lapse rates.
However, if sufficient buoyancy can develop by late afternoon, there
will be potential for surface-based supercell development, which
could pose a localized tornado and damaging-wind threat.

Farther south, the coverage and persistence of early-day convection
across the southern Plains remain somewhat uncertain, though there
may be a tendency for convection to weaken and/or shift northward by
early afternoon. The greatest confidence in substantial diurnal
destabilization is from southwest OK into northwest TX and the
Edwards Plateau, where heating of a very moist airmass will result
in MLCAPE increasing to near/above 1500 J/kg, despite poor midlevel
lapse rates. Renewed storm development is expected from late
afternoon into the evening, in advance of the approaching
mid/upper-level low. Moderate midlevel flow will provide sufficient
deep-layer shear for storm organization.

While supercells will be possible initially, generally
front-parallel flow and increasing storm coverage will likely lead
to more of a linear mode with time. Strong to severe gusts appear to
be the most likely hazard, though isolated hail also appears
possible across southwest TX, where somewhat stronger
destabilization may occur. Also, while low-level flow will be weaker
compared to areas farther north, some increase in effective SRH is
expected during the evening, which could support a localized brief
tornado threat within the very moist environment.

An isolated severe threat could persist into parts of central TX/OK
overnight, though diminishing buoyancy with time and eastward extent
should result in an eventual weakening trend.

..Dean/Weinman.. 09/30/2026


Read more
https://www.spc.noaa.gov/products/outlook/day1otlk_1200.html