961
ACUS01 KWNS 280048
SWODY1
SPC AC 280046

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0746 PM CDT Sun Sep 27 2026

Valid 280100Z - 281200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Organized severe storms are not expected tonight.

... Synopsis ...

Several different regimes of thunderstorms are ongoing this evening
across the CONUS and others may develop overnight.

The first of these is across portions of Texas and far southern
Oklahoma. Here, a moist airmass combined with strong diurnal heating
and weak surface convergence have supported scattered
strong-to-marginally severe thunderstorms. The strongest of these
storms will continue to pose a gusty wind threat for another couple
of hours before nocturnal cooling weakens low-level lapse rates and
decreases the greater wind potential.

A second area is in and near western portions of Cherry County,
Nebraska. Here, a couple of intense supercells have developed this
afternoon, with MRMS MESH suggesting hail perhaps in excess of 3" in
diameter at various times this afternoon. These nearly stationary
storms will persist for another couple of hours before weakening
with the loss of diurnal heating.

A third area is located across the central Rockies where large-scale
ascent associated with a subtle short-wave trough embedded in the
southwest mid-level flow has combined with modest instability. These
thunderstorms should progress eastward during the evening hours.
Additional thunderstorms are likely to form ahead of these across
the northern Plains this evening and overnight as low-level warm-air
advection strengthens.

Elsewhere, a couple of ongoing thunderstorms will persist for a few
more hours across northern California and southern Oregon, and a
couple of lightning strikes cannot be ruled out overnight across
portions of southern and eastern New England as the intense, nearly
stationary east coast cyclone begins to slowly move northward toward
the southern New England coast.

..Marsh.. 09/28/2026

$$