SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1219 PM CDT Sat Apr 20 2019
Valid 211200Z - 221200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
KANSAS AND SOUTHERN NEBRASKA....
Marginally severe thunderstorms with a potential for hail and strong
wind gusts will be possible across parts of the central Plains on
Sunday afternoon and evening.
A weak lead shortwave impulse will eject across the central Plains
ahead of the main western trough on Sunday. Boundary layer moisture
will increase ahead of a developing surface low over the central
High Plains and dewpoints will reach into the upper 50s to low 60s.
A cold front extended from southern MN into southwest NE during the
afternoon will drop southeast across the central and into the
southern Plains through the overnight hours.
As forcing increases across the region, midlevel capping should be
sufficiently weakened and isolated to widely scattered thunderstorms
are expected to develop in the vicinity of the surface low and cold
front across northeast CO. With time, thunderstorms will develop
eastward along the cold front across portions of northwest into
central KS and south-central NE where instability will be maximized
(MLCAPE from 500-2000 J/KG) and midlevel lapse rates will be on the
order of 7.5-8.5 C/km. Despite weak to moderate instability, deep
layer shear will be modest, around 25-35 kt, marginally supporting
supercells and storm clusters, but stronger updrafts should be
fairly transient/short-lived. Storms will struggle to become
surface based given the weak elevated mixed layer and timing
(evening into overnight) and should remain elevated. As such, a
marginal risk for hail and possibly a few strong wind gusts will
accompany storms the develop from late afternoon into late tomorrow
...MAXIMUM RISK BY HAZARD...
Tornado: 2% - Marginal
Wind: 5% - Marginal
Hail: 5% - Marginal