- Day Three
acus03 kwns 180743
Storm Prediction Center ac 180742
Day 3 convective outlook
National Weather Service Storm Prediction Center Norman OK
0142 am CST Mon Nov 18 2019
Valid 201200z - 211200z
..no severe thunderstorm areas forecast...
scattered thunderstorms are possible Wednesday over the Desert
Southwest, with isolated activity into the Southern Plains. Severe
storms are not expected.
An upper low is forecast to move from Southern California into Utah on
Wednesday with the left exit region of a cyclonically curved
midlevel speed Max nosing into Arizona during the day. While scattered
storms will likely be ongoing Wednesday morning over Arizona with limited
heating, strong cooling aloft will aid destabilization with a few
hundred j/kg of MUCAPE expected. Storms are likely to be focused
over central and Southeast Arizona where southerly winds will lead to
upslope flow. While veering winds with height will conditionally
favor supercells, it is uncertain whether sufficient instability
will develop. As such, will maintain < 5% severe coverage.
A lead shortwave trough will lose amplitude as it moves from
southwest Texas into the Central Plains, where low pressure will
develop ahead of a cold front. This front will extend roughly from
Dalhart Texas to Omaha NE at 00z Thursday, with southerly surface winds
bringing mid to upper 50s f dewpoints northward across OK and
eastern Kansas. Although moist, the boundary layer will remain cool and
capped. However, midlevel moisture as well as sufficiently steep
lapse rates aloft will lead to elevated instability rooted near 700
mb, with scattered showers and storms from eastern nm into parts of
OK and Kansas during the day. Despite strong effective shear, weak
instability should preclude any severe hail chances.