U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus02 kwns 260600 
Storm Prediction Center ac 260559 

Day 2 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1259 am CDT Tue Sep 26 2017 

Valid 271200z - 281200z 

..no severe thunderstorm areas forecast... 

the severe weather threat across the Continental U.S. Is expected to 
be low on Wednesday. 

An upper low/trough is forecast to linger over the Desert 
Southwest/Four Corners area Wednesday, making only very slow 
north/northeast progress. Meanwhile, ridging aloft is progged to 
remain over the south-central and southeast portions of the country. 
Farther north, northern stream troughing will continue spreading 
east across the eastern half of Canada and adjacent portions of the 
U.S. -- From the Great Lakes east to New England through the end of 
the period. 

At the surface, a cold front initially extending from a western 
Quebec surface low southwest across the mid Ohio and lower 
Mississippi valleys will make steady eastward progress across the 
eastern half of the country, while high pressure spreads east in the 
wake of the front to encompass a large portion of the Continental U.S. Through 
the period. 

Two main areas of deep moist convection are expected -- one over the 
southwest and south-central portions of the country ahead of the 
western low/trough, and a second over the northeast ahead of the 
advancing northern-stream feature. In the southwest, shear on the 
southeast fringe of the upper circulation center may be sufficient 
to promote a few stronger cells, with sub-cloud evaporation aiding 
potential for gusty winds in a few locales. However, any risk for 
severe weather remains too low to prompt inclusion of a risk area at 
this time. Meanwhile in the northeast, some destabilization ahead 
of the front will combine with ample deep-layer shear, resulting in 
an environment that could conditionally support a couple of 
stronger/locally severe storms. However, with much of the 
convection expected to remain north of the international border and 
questions regarding coverage farther south into the Vermont/NH/ME 
vicinity at this time, will refrain from areal highlights in this 

.Goss.. 09/26/2017