Weather across America

(NATIONAL) Cool for the Northeast with a freeze possible in the Upper Ohio Valley, much above average high temperatures continue for much of the central and western U.S., precipitation chances inland from the West Coast to the Northern Rockies/Plains, and some lingering rain showers and breezy winds for New England. 

High temperatures from the Great Lakes into the Northeast are forecast to remain much below average following a frontal passage, with 40s and 50s for the interior and 60s closer to the coast. Frost and Freeze related advisories are in place for portions of the Upper Ohio Valley Monday morning as low temperatures drop into the low to mid-30s. High temperatures should warm a bit on Monday as conditions moderate.  

Broad upper-level ridging over the central-western U.S. will remain in place on Sunday with forecast highs once again running 10-20 degrees above average. Highs will range in the 60s and 70s from the Great Basin into the Rockies and Northern/Central Plains, the 80s for the Lower Mississippi Valley and Southern Plains, and the 90s for the Desert Southwest. 

The ridge will shift a bit eastward on Monday, allowing for some cooler temperatures in the west as a frontal system approaches while highs soar into the upper 70s and 80s from the Central Plains into the Middle Mississippi Valley. 

Highs will be closer to average further into the Southeast and Florida, with 70s and some 80s forecast.  An upper-level trough will help to push a quasi-stationary frontal system lingering in the northwest south and eastward across the region, with incoming Pacific moisture helping to spread precipitation chances inland. Light to moderate showers and thunderstorms are forecast from northern California into the northern Great Basin/Rockies on Sunday, shifting towards the Northern Plains by Monday. 

Some snow may mix in for higher mountain elevations. More potent snow chances should begin to arrive by early Tuesday morning in the northwest and the Northern Rockies as another system drops southward from Canada. Highs Sunday will be below average for much of California, especially northern portions where the rain is expected, with mainly 60s forecast. 

Noted above average highs for much of the Interior West Sunday will fall closer to average Monday following the frontal passage, with 50s and 60s expected. As the frontal system continues east, increasing moisture associated with Tropical Storm Norma currently in the Pacific is forecast to bring showers and thunderstorms to the Southern Plains overnight Monday, with some locally heavy rainfall possible.