Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS01 KWNS 250046
SPC AC 250045
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 PM CDT Mon Apr 24 2017
Valid 250100Z - 251200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
Isolated thunderstorms remain possible across the eastern Carolinas
this evening, with isolated weak thunderstorms expected to continue
from the Rockies into the central Plains.
Center of upper low has progressed to near the GA/SC border this
evening. Latest water vapor imagery depicts significant mid-level
drying has wrapped into this feature which appears to be partly
responsible for weak buoyancy that is supporting a small cluster of
weak thunderstorms across southern SC. 00z sounding from CHS
supports this mid-level drying with MU CAPE on the order of 800
J/kg. In the absence of significant forcing this activity should
gradually weaken over the next few hours.
00z soundings across the interior West depict steep mid-level lapse
rates north of a strengthening mid-level jet that extends from CA
into the central Rockies. Diurnal heating appears mostly
responsible for scattered weak convection along the cyclonic side of
the jet and isolated lightning with this activity should gradually
wane later this evening with loss of heating. However, large-scale
forcing for ascent will increase across the central Plains late
tonight as LLJ increases over OK/KS. Weak elevated convection
should evolve across this region and the strongest updrafts should
attain heights necessary for lightning discharge.