Weather across America

(NATIONAL) Dangerous heat to continue across the Southwest before cooler temperatures arrive, dangerous heat to continue across the Southern/Central Plains then shift farther north and east, and strong to severe storms possible across portions of the Northern/Central Plains, Ohio Valley, and Mid Atlantic.

Another night of record-setting heat is expected from the Desert Southwest to the Lower/Middle Mississippi Valley, with nighttime temperatures forecast to bottom out in the upper 70s and 80s in many locations. This will likely be the last in this stretch of record-setting days in the Southwest, as a strong Pacific cold front drops into the region, introducing notably cooler temperatures into the region on Monday.  

However, the heat will expand across the central into the eastern U.S., with record-breaking temperatures extending north into the Central Plains and east from the mid Mississippi Valley to the Carolinas on Monday.  

Temperatures will begin to moderate across the Plains on Tuesday as the front moving through the West begins to impact the region. Ahead of the front, the heat will continue to build, with well-above normal to record-breaking temperatures expected from the Midwest to the Carolinas on Tuesday.  

In addition to cooler temperatures, the system moving across the West is expected to bring additional precipitation to the Pacific Northwest, northern California, and the Northern Rockies through the remainder of the weekend. Flood Watches and Warnings are in effect across parts of Washington, Oregon, Idaho, and Montana where the combination of moderate to heavy rain, melting snow, and saturated soils is promoting significant rises along the area's rivers and streams.  

As the system moves east of the Rockies, a strong area of low pressure is forecast to develop over southern Canada late Monday, promoting windy conditions and rain changing to snow across portions of the Northern Rockies. A Winter Storm Watch remains in effect late Monday and Tuesday for the West Glacier Region and the Northern Rocky Mountain Front in Northwest Montana, where several inches of heavy wet snow can be expected for areas above 5000 ft.  

Strong winds, low humidity, and warm temperatures ahead of the front will contribute to critical fire weather conditions, prompting Red Flag Warnings across portions of southern Nevada, northern Arizona, southern Utah, southern Colorado, and northern New Mexico today. Critical Fire Risk will shift into the Four Corners region, northern New Mexico and southeastern Colorado on Monday.  

Unsettled, stormy weather is expected from the Northern Plains to the Mid Atlantic over the next few days, with a series of upper disturbances bringing the threat for severe weather across the region.  

On Monday, scattered severe thunderstorms are expected to develop once again across portions of the northern Plains, and from parts of the Midwest into the Great Lakes and the Ohio Valley. Once again, these storms may produce large hail, damaging winds, and a few tornadoes. 

The threat of severe thunderstorms spreads into the Upper Midwest, Northern Plains and Mid-Atlantic on Tuesday as the strong cold front moves out over the region.