- Day Three
acus02 kwns 240558
Storm Prediction Center ac 240557
Day 2 convective outlook
National Weather Service Storm Prediction Center Norman OK
1257 am CDT Mon Apr 24 2017
Valid 251200z - 261200z
..there is a slight risk of severe thunderstorms across parts of
northeast Oklahoma...southeast Kansas and Missouri...
..there is a marginal risk of severe thunderstorms outside of the
slight risk area across parts of northeast Oklahoma...southeast
Kansas and Missouri...
Thunderstorms associated with large hail and isolated wind damage
are expected to develop across parts of northeast Oklahoma,
southeast Kansas and southwest Missouri Tuesday evening.
..northeast Oklahoma/southeast Kansas/southwest Missouri...
An upper-level trough is forecast to move across the southern and
central rockies on Tuesday as a mid-level jet rounds the base of the
trough. At the surface, a cold front is forecast to advance
southward across the Central Plains reaching eastern Kansas and
northern Oklahoma by late afternoon. A cap should prohibit
convective development along the front during the day. However, the
cap should weaken by early evening, which combined with increasing
low-level convergence along the front, should result in thunderstorm
development in the vicinity of southwest Missouri, southeast Kansas
and northeast Oklahoma.
Ahead of the cold front, moisture advection will take place
throughout the day. Surface dewpoints are forecast to reach the
lower to mid 60s f from northeast Oklahoma into western Missouri.
NAM forecast soundings along the corridor early Tuesday evening at
Tulsa, Oklahoma and Springfield, Missouri have MLCAPE near 1500 j/kg
with 0-6 km shear of 50 kt. This combined with steep lapse rates in
the low to mid-levels may result in supercell development associated
with large hail. However, thunderstorms may also congeal into lines
along the front which would be more favorable for wind damage. The
dominant type of severe weather will depend upon which storm Mode
that is most favored.
An upper-level trough will move across the southern and central
rockies on Tuesday as a cold front moves southward into the Texas
Panhandle. Thunderstorms are forecast to develop along the cold
front Tuesday evening where forecast soundings show enough
instability and steep lapse rates sufficient for hail. At this time,
do not have enough confidence that the hail threat will meet
criteria for a marginal severe threat area.