SPC AC 171230
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0630 AM CST Mon Jan 17 2022
Valid 171300Z - 181200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms are not forecast across the contiguous United States.
...Synopsis/Discussion...
Mid/upper-level troughing in the eastern CONUS will shift eastward
and offshore all but New England by the end of the period. This
will occur as the dominant subsynoptic cyclone now over the
Mid-Atlantic ejects northeastward to southeastern Canada through
tonight and weakens considerably, deteriorating to a small, open
shortwave trough. In its wake, northwest flow aloft will prevail
over most of the northern and eastern CONUS, while a post-cold-
frontal continental/polar boundary layer generally precludes
thunderstorm potential. Elevated convection in the precursory warm
conveyor may yield brief/isolated lightning near ACK in the next
couple hours, but potential appears too low/conditional to introduce
a categorical/10%-coverage area.
Meanwhile, a closed mid/upper cyclone -- evident in moisture-channel
imagery offshore from CA -- will move inland across southern CA
tonight, but with too little moisture/instability to support
thunderstorms.
..Edwards/Broyles.. 01/17/2022
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
|