U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus03 kwns 240717 
Storm Prediction Center ac 240716 

Day 3 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0216 am CDT Friday Oct 24 2014 

Valid 261200z - 271200z 

..no severe thunderstorm areas forecast... 

isolated to scattered thunderstorms are anticipated on Sunday night 
over the upper Midwest. Small hail may occur but confidence is too 
low to identify a marginal severe-hail area. 

Broad middle-level trough will shift east from the northwest to the northern 
Great Plains through early Monday...with a downstream ridge moving from 
the upper Midwest to the Great Lakes. Primary surface cyclone should 
track from the Lee of the southern Canadian rockies across the southern 
prairie provinces with a cold front sweeping east and reaching the 
upper Midwest to central Great Plains. A warm front will advance NE 
over the upper MS valley and Midwest. 

..upper Midwest... 
Strengthening low-level warm air advection should yield isolated to scattered 
elevated convective clusters Sun night. Guidance differs with the 
degree of elevated buoyancy as the NAM and WRF-based sref members 
appear more aggressive with 850-700 mb moisture return compared to 
the GFS and non-NCEP models. Leaning with the less aggressive 
guidance...the predominant southwesterly flow regime should effectively cap 
thunderstorm development to along the eastern periphery of the moisture plume 
where buoyancy should be weak. Given close proximity to the 
departing middle-level ridge...effective shear should remain moderate. 
In conjunction with a probable cluster Mode...it appears premature 
to highlight what may only be a narrow corridor of marginal severe 
hail potential. 

.Grams.. 10/24/2014