Published 2:01 PM EDT May 7, 2020As if our world wasn't already off-kilter: Snow and shock-the-system cold will numb the Mother's Day weekend for many across the U.S.
Forecasters warn of a bizarre spring pattern that is expected to sweep unseasonably raw weather east of the Rockies. The arctic plunge could shatter dozens of records and notch temperatures chillier than Christmas Day in some cities.
Overall, highs will hover around 10 to 25 degrees below average Friday into Sunday in the East.
"This is certainly a powerful shot of arctic air and will bring the coldest Mother's Day weekend in quite some time," CNN meteorologist Taylor Ward said.
A frost is possible as far south as the Carolinas and Southeast, according to the Weather Channel, and wet snow is likely Friday night and Saturday in parts of the Northeast. Lake-effect snow is possible around the Great Lakes.
The extreme weather is fueled by two high pressure systems – one near Greenland and another "omega block" pushing north from the West Coast – that will force the jet stream to dive southward over the Great Lakes and Northeast, the Weather Channel said.
An intensifying low pressure system in the Northeast could transform into a bomb cyclone, the equivalent of a winter hurricane. A storm is called a bomb cyclone when it has undergone bombogenesis, which occurs when barometric pressure drops by 24 millibars in 24 hours.
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This weekend's storm could become a bomb cyclone by the time it moves into the Gulf of Maine on Saturday, the Weather Channel said. The storm could be strong enough to set all-time pressure records for May along the Maine coast, according to the National Oceanic and Atmospheric Administration's Weather Prediction Center.
As the system pushes into the Ohio Valley and Northeast, wet snow is likely Friday afternoon into Friday night, forecasters said. Heavier snow – more than 6 inches is possible – could lead to power outages in parts of New England on Saturday, the Weather Channel said.
Another odd May phenomenon could rumble in the sky, according to the National Weather Service office in Binghamton, New York: thundersnow. When there is a strong enough upward motion of air – known as convection – and plenty of moisture, snowflakes and sleet pellets collide, creating a static charge that produces thundersnow.
Widespread record low temperatures as far south as Alabama and Mississippi are also expected Saturday, according to the National Weather Service.
The Great Lakes, Ohio Valley and parts of the Northeast will plunge into the 20s in the early morning hours; highs will only hit the 40s for many Friday and Saturday, forecasters said.
Cities where all-time May record lows could be broken, according to the Weather Channel: Detroit; Lexington, Kentucky; Pittsburgh; Knoxville, Tennessee.
"Those with vulnerable plants may want to cover them to limit damage potential" Saturday night, the Capital Weather Gang warned the Washington area.
The winter weather pattern comes in sharp contrast to near record heat across Southern California, the Desert Southwest and the southern Rockies.
Contributing: Doyle Rice
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