Weather across America

(NATIONAL) Severe thunderstorms and instances of flash flooding possible from the ArkLaTex region to the Ohio Valley, a swath of light to moderate snowfall forecast over parts of the Midwest and Great Lakes, record-breaking warmth expected to continue throughout parts of the Mid-Atlantic and Southeast, and a cold front entering the Northwest and Northern Rockies to bring locally heavy snowfall across the higher terrain.

A lifting shortwave trough over the Central Plains Monday evening and an associated area of low pressure over the Middle Mississippi Valley will lead to chances for severe weather, flash flooding, and snowfall on the cold side of the system. For Sunday, an attached cold front extending to the east and into the northern Mid-Atlantic is expected to be the focus for numerous showers and thunderstorms from southern Missouri through much of the Ohio Valley as it stalls and slowly lifts northward. Heavy rain associated with the slow-moving thunderstorms could produce rainfall totals up to 3 inches. This amount of rain in a relatively short period of time could trigger scattered flash floods. In order to highlight the potential flash flooding threat, the Weather Prediction Center has issued a Slight Risk (level 2/4) of excessive rainfall for this region. 

The excessive rainfall threat continues over the Ohio Valley into Monday as a potent cold front eventually sweeps toward the Appalachians and Gulf Coast, with additional rounds of thunderstorms possible. Flood Watches are also currently in effect from southern Missouri to central Kentucky. The threat of damaging wind gusts, large hail, and isolated tornadoes also exists as thunderstorms develop and progress across the Lower Mississippi and Ohio Valleys Sunday night. Specifically, there remains a greater risk of severe weather over northern Arkansas and southern Missouri this evening. The Storm Prediction Center (SPC) has issued an Enhanced Risk (level 3/5) of severe thunderstorms here, with damaging winds gusts and a few tornadoes possible. On Monday, severe thunderstorms may accompany the advancing cold front from West Virginia to central Alabama, where SPC has issued a Slight Risk (level 2/5) of severe thunderstorms.

Farther north, colder air has filtered into the Central Plains, Midwest, and Great Lakes, which will support accumulating snowfall between northeast Kansas Sunday night and central Michigan by Monday. Although the system will be fast-moving, a burst of moderate to locally heavy snow could create low visibility and dangerous driving conditions for the Monday morning commute. Overall, snowfall amounts are expected to remain below 6 inches, with the heaviest amounts found from southern Wisconsin to central Michigan. By late Monday, the low-pressure system and wintry precipitation will shift into far northern New England. Cold and blustery winds behind the cold front could lead to scattered lake effect snow showers on Tuesday morning.

Meanwhile, much of the eastern U.S. enjoyed a warm Sunday ahead of the approaching weather system. This early taste of Spring will continue into Monday throughout the Mid-Atlantic and Southeast. Widespread highs into the 70s and 80s will extend from the central Gulf Coast to New Jersey. These temperatures equate to around 20 to 30 degrees above average in the Mid-Atlantic, with dozens of daily records likely to fall across this section of the Nation as well. Temperatures will crash back to near normal levels behind a cold front on Tuesday.

Elsewhere, the next cold front to enter the Lower 48 will swing into the Northern Rockies and Northwest by Monday night. Along with a drop in temperatures, moderate to locally heavy snow is possible for much of the higher terrain of Idaho, Montana, and northwest Wyoming into Tuesday. Snowfall totals greater than 6 inches are anticipated, with lighter amounts located over the Cascades.