As the St. Patrick's Day Storm pushes slowly inland from the West, there is the potential for an outbreak of violent thunderstorms and tornadoes over the Plains starting on Sunday.
Essentially two seasons will do battle over the Plains during the first part of next week: summer and winter.
As colder air tries to push out of the Rockies, it will cause warm, moist air to rise violently and will be given extra energy by a strong jet stream overhead.
While the actual magnitude of the outbreak has yet to be determined, indications are that there is an elevated risk of tornadoes.
During Sunday, the risk extends from portions of western Texas to part of South Dakota.
During Monday, the risk extends from central, northeastern and South Texas to Missouri and perhaps part of Iowa.
The potential for severe thunderstorms (including tornadoes) will extend beyond Monday and will push farther east as next week progresses.
In addition to the tornado threat, severe thunderstorms will bring the whole nine yards of danger with large hail, damaging wind gusts, frequent lightning and flash flooding.
Prior to the risk next week, there will be a few pockets of locally strong, drenching thunderstorms over the Mississippi and Tennessee valleys, western Texas and the Southeast through Saturday as the May-like pattern continues.
In addition, the St. Patrick's Day storm will bring locally severe thunderstorms over portions of California and the Southwest over this weekend.
Ice, rain and snow are slamming the United States from Texas to Maine.
Thunderstorms in parts of the South this weekend may become strong enough to threaten lives and property.
As California heads into its third consecutive dry winter with no relief in sight, firefighters continue to battle a late-fall blaze in Big Sur.
Similar to the days prior to Thanksgiving, the worst weather will focus on the days prior to Christmas as millions of travelers take to the roads and skies in the U.S. and southern Canada.
An abrupt and abnormal cold wave gripped parts of southeastern Texas in early December, catching many off-guard, including two native Southern California bobcats recently transferred to the area.
Wintry and violent weather will avoid central Pennsylvania through the weekend.
Perey, IL (1967)
An F2 tornado carried women and her baby 400 feet; they survived.
Wind gusts to 91 mph across the San Joaquin Valley - hundreds of cars and trucks buried by blowing dust.
N. California & Oregon (1964)
Great warm surge and torrential rains on deep snow cover; record floods followed.