Weekend Weather Preview

A storm system in the Great Plains amplifies through the weekend, transforming into a mess of strong to severe storms as Sunday enters the fray.
 
Saturday
In the Northwest, a colder air mass settles over the region, bringing moderate snow squalls that focus mostly east of the Cascades. However, some isolated lowland rain is expected in the valleys and parts of the Pacific Northwest, with a wintry mix along the mid-elevations. Bands of snow and wintry mix will stretch over a swath of the northern Plains in the Upper Midwest by nighttime as they stretch eastward.

East of the Rockies and toward the Lower Midwest, scattered showers and thunderstorms will coalesce through Saturday under multiple disturbances. Some isolated severe storms are likely to arise, with isolated hail and severe wind gusts toward the evening. Further south, the storm system hanging onto the Gulf Coast will lose its strength as Saturday moves forward, bringing weaker yet still drenching rainstorms into the South and lightning along for the ride.

One last corridor of storms will hold wintry implications in the interior of the Northeast under a swift low's warm front. Although light showers will fall in the Lower Northeast, wintry mix and light snow will fall from the northern Great Lakes through Maine, mostly dissipating by midnight. Otherwise, a dry day is only in store for the Southwest.

Temperatures begin to clash on Saturday as storms shake up the regime of heat over the nation. Expect more-than-balmy highs in the 80s and 90s in the southern Plains and the far Southeast into Florida. Pleasant 60s and 70s arrive to warm the rest of the U.S. Southern Tier and the Lower Midwest, while cooler 40s and 50s litter the Great Lakes, the Intermountain West, and the Pacific Northwest. Colder temperatures expand as compared to Friday, with 30s and some 20s speckled in the Rockies, northern Plains, and the interior Northeast.
 
Sunday
A messy weather forecast is in store for much of the nation on Sunday thanks to a potent low pressure system and multiple frontal systems.

This low pressure system will drift from the Midwest into the Northeast for the conclusion of the weekend. Ahead of the low pressure, there will be a warm front that tries to lift north over the eastern U.S. Meanwhile, two cold fronts will impact the nation’s midsection, with one moving through the south-central U.S. and another nearly stationary over the Rockies and High Plains.

Extensive precipitation will be found throughout the eastern two-thirds of the nation as a result. Rain showers and thunderstorms will occur from the southern half of the Plains eastward to the Southeast and as far north as the Midwest, Ohio Valley, Mid-Atlantic and southern New England. Strong to severe thunderstorms will also be likely in these areas, with heavy rain, damaging winds, large hail and a few tornadoes all possible.

Things get more complicated for the rest of the central and eastern U.S. Expect mainly light to moderate snow showers for the Rockies and High Plains. However, snow could mix with and perhaps change over to rain for some areas of the High Plains. Snow or a mix of snow, sleet, freezing rain and rain is anticipated for the northern half of the Plains, Upper Mississippi Valley, Great Lakes and interior Northeast during the morning. As warmer air moves in due to the warm front, this mixed wintry precipitation will likely change over to rain for most areas during the afternoon and evening.

At the same time, a Pacific storm system will come crashing into the western U.S. Precipitation will initially begin in the northern half of California and spread north and east throughout the day. Most areas should just see occasional rain showers. Though, the highest elevations of the Cascades and Sierra Nevada will see snow or a rain/snow mix. A few rain showers could also move into southern parts of California later in the day.

Temperatures will generally be in the 30s and 40s across northern California, the Great Basin, northern/central Rockies, northern Plains and Upper Mississippi Valley as well as the interior Northeast. However, the tallest peaks in the Rockies and New England could report highs only in the 20s. Fifties and 60s and await the Northwest, central California, the southern Rockies and central Plains into the Great Lakes, Ohio Valley and the rest of the Northeast. Warmer 70s and 80s will be seen in the Desert Southwest, southern Plains, Midwest, Southeast and Mid-Atlantic. A few 90s are also possible in Texas.