SPC AC 171936
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0136 PM CST Fri Nov 17 2017
Valid 172000Z - 181200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
Thunderstorms are expected tonight across much of the Midwest from
Missouri to Ohio, with more isolated afternoon and evening
thunderstorms possible across parts of the central Rockies.
...MO and IL late tonight...
Latest CAM guidance suggests perhaps an elevated storm or two right
at the end of the day 1 period, from far northeast MO into west
central IL around 12Z. Forecast soundings indicate marginal
instability levels for severe storms, but some hail may be present.
Given such a limited area of potential and sparse storm
expectations, will maintain a general thunder area for tonight.
.PREV DISCUSSION... /ISSUED 1010 AM CST Fri Nov 17 2017/
A broad upper trough is deepening across the western states today,
while a band of strong west-southwesterly mid-level winds extends
from the Great Basin into the Midwest. Southerly low-level winds
over the MO/IL/IN will help moisten/destabilize the air mass,
leading to scattered showers and a few thunderstorms - mainly after
dark. One cluster of convection will move across northern IN and
southern Lower MI this evening. At this time, no severe storms are
anticipated with this activity.
Late tonight, 12z model guidance continues to indicate a risk of
thunderstorms developing after 10z near an approaching cold front
over north-central MO and central IL. Forecast parameters suggest
some risk for hail in the strongest cells, but limited
areal/temporal confidence precludes an upgrade at this time.
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z