983
ACUS48 KWNS 230922
SWOD48
SPC AC 230920

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0320 AM CST Sat Nov 23 2024

Valid 261200Z - 011200Z

...DISCUSSION...
On Tue/D4, an upper trough will pivot northeastward from the Great
Lakes into southern Quebec, with temporary zonal flow across much of
the CONUS. Moisture along the central Gulf Coast will be quickly
shunted offshore as a cold front pushes south.

Models are in good agreement depicting another shortwave trough over
the central Rockies on Wed/D5, with some amplification possible into
the southern Plains Wed night. This trough will maintain a positive
tilt on Thu/D6 with a 65-75 kt 500 mb speed max extending from TX to
the TN/OH Valleys by 00Z Fri/D7.

During the day on Wed/D5, low pressure is forecast to develop over
OK, and will translate east/northeast into KY/TN Wed night ahead of
a cold front. South of this front, a relatively large area of mid to
upper 60s F dewpoints will develop, especially Wed night, from
eastern TX across LA and MS. Given the positive tilt of the upper
trough, winds around 850 mb will be out of the west/southwest,
reducing low-level shear somewhat. In addition, speeds are not
expected to be particularly strong. Still, thunderstorms will likely
develop late Wed/D5 over the lower MS and TN Valleys near the cold
front. Greater thunderstorm coverage is expected on Thu/D6 over much
of the Southeast and ahead of a strengthening cold front. Even with
veered low-level winds, the strong deep-layer shear and focus along
the front may provide a risk of severe/wind storms. This area will
be monitored for upgrades in later outlooks as predictability
increases.

From Fri/D7 into Sat/D8, a secondary speed max moving out of the
upper MS Valley/Great Lakes will likely phase with the southern
trough, eventually enveloping the eastern CONUS, and reinforcing
stable air behind the cold front.

..Jewell.. 11/23/2024