- Day Three
acus03 kwns 250659
Storm Prediction Center ac 250658
Day 3 convective outlook
National Weather Service Storm Prediction Center Norman OK
0158 am CDT Fri may 25 2018
Valid 271200z - 281200z
..there is a marginal risk of severe thunderstorms across parts of
the northern High Plains and into the Dakotas...
Strong/locally severe storms will be possible across portions of the
northern and Central High plains and into the Dakotas.
While gradual progression of a weak/low-amplitude trough will
continue across the Great Lakes and into the northeast/New England
Sunday, the upper low over the interior west is forecast to become
more cut-off from the flow, and thus linger quasi-stationarily
across the Great Basin vicinity through the period.
At the surface, Lee troughing will remain across the High Plains,
while the Gulf of Mexico low is progged to shift northward with time
toward the coast.
..parts of the northern/Central High plains into the Dakotas...
As the upper low lingers over the intermountain region, afternoon
heating/destabilization over the High Plains in conjunction with
weak ascent associated with subtle features aloft rotating around
the parent low will contribute to isolated/scattered afternoon storm
development. With moderate southerly mid-level flow atop the High
Plains, a few stronger/possibly rotating storms will likely evolve,
with attendant/isolated risk for damaging winds and hail. Evening
intensification of a southerly low-level jet may permit one or two
clusters of storms to persist eastward into the Dakotas, where
low-end severe risk may continue through the evening.
..central and eastern Gulf Coast region...
Models generally suggest that the tropical/sub-tropical low
initially over the eastern/central Gulf of Mexico will continue
moving northward, possibly making landfall during the period. While
low-level flow surrounding the system may remain sufficient to
support low-level rotation within convective cells, uncertainty
regarding the progression and evolution of the system precludes an
areal delineation of any tornado risk at this time. Probabilities
may be included in later outlooks over portions of the central
and/or eastern Gulf Coast region as details regarding this system
become a bit more certain.