A wave of low pressure over the Central Gulf Coast moves to the southern Mid-Atlantic by Wednesday, followed by a second wave of low pressure over the Central Gulf Coast on Thursday.
The associated front along the Central Gulf Coast will trigger showers and thunderstorms; some of the thunderstorms may become severe.
Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Central Gulf Coast through Wednesday morning.
The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes.
In addition, heavy rain with these thunderstorms will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain.
The threat of severe thunderstorms moves eastward to the Southeast as the associated front produces showers and thunderstorms.
Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Southeast from Wednesday through Thursday morning.
The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes.
The threat of excessive rainfall also moves eastward along the front as the associated heavy rain creates localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain.
Meanwhile, a front extending from the Upper Great Lakes to the Central Rockies will move eastward to the Northeast/Mid-Atlantic Coast by Friday evening.
The front will trigger light snow over parts of the Upper Great Lakes through Thursday morning.
The front, in combination with the area of low pressure over the southern Mid-Atlantic, will aid in producing two to four inches of snow over parts of the interior Northeast on Wednesday.
Furthermore, upper-level energy moving over the Pacific Northwest will push the western end of the front to move southward over the Great Basin into the Southwest and Southern Rockies by Thursday.
Overnight Tuesday, the energy will produce coastal rain and light snow over parts of the Northwest into the Northern Rockies that will expand into parts of the Great Basin and Central Rockies on Wednesday.
The rain will end over the Northwest by late afternoon on Wednesday.
The snow will be heavy over the higher elevations of the Great Basin and Central Rockies.
Additionally, light to moderate snow will also develop over parts of the Central Plains on Wednesday.
Along with the snow, cold temperatures will be over the Northern Rockies/Northern/Central High Plains, with some locations experiencing record or tied for record low temperatures on Wednesday and Thursday morning.
Heavy snow will develop over the Central Plains into the Middle Mississippi Valley as a wave of low pressure moves out of the Central Rockies on Thursday.
Moreover, as the system moves out of the Rockies, gusty wind, low humidity, and dry fuels have contributed to an area of Critical Risk of fire weather over the Southern Rockies into the Southern High Plains on Wednesday. ■