An exceptionally active weather pattern will send multiple large storm systems slicing across the country. Air masses will wage war, whipping up possible tornadoes and blizzards. Monster waves will batter the California coastline, while up to feet of snow and hurricane-force winds will plaster summits in the Sierra Nevada. In the East, after cold and snow this weekend, warmth and flooding rains could sweep north next week.
The meteorological mayhem, fueled by a strong El Niño climate pattern, will culminate in a possible cold air outbreak in a little more than a week that could send temperatures plummeting across much of North America.
Here are seven weather extremes to watch out for:
1. An East Coast snowstorm this weekend
First up is a storm set to sweep from the Mid-Atlantic to east of New England this weekend. Cold air will wrap around it, throwing moderate to heavy snows inland while a cold rain drenches the coastline. Some icing could occur in western parts of Virginia and North Carolina.
A general 4 to 8 inches of snow is probable from interior Pennsylvania to the southern Hudson Valley, with an additional strip of plowable snow in New England away from the immediate southern coastline. Localized totals may reach the double digits, especially in the Boston to Manchester, N.H., corridor and west toward Albany, N.Y.
“There is still uncertainty in the track and intensity of the system,” wrote the National Weather Service forecast office serving Boston. “This will influence the [snow] totals, [precipitation] types and exact impacts to our region.”
Closer to the coast, around an inch of rain is expected. In between, the Interstate 95 corridor sits near the rain-snow line, but minimal snow accumulation is forecast for New York City, Philadelphia, Baltimore and Washington.
The quick-moving storm will sweep through between Saturday morning and Sunday afternoon before exiting.
2. Big California waves are back this weekend
It’s been hardly a week since large breaking waves sent seawater spilling into coastal communities in California and injuring several people. Offshore wave heights between 28 and 33 feet prompted high surf warnings, and a few breakers topped 40 feet. Now a new round of big waves is about to pound the coast.
Some are calling them “sneaker waves,” a loosely defined term to describe surprise waves twice as tall as surrounding waves. While confidence is high that coastal flooding in the Saturday to Monday time frame won’t be as severe as last week’s episode, the Weather Service office serving southwestern California is urging residents to swim only near life guards and to stay away from rock jetties.
Along California’s Central Coast, peak surf heights between 10 and 16 feet are expected, with 5 to 8 feet at the Los Angeles beaches.
On Sunday, the European model is projecting offshore waves of 30 to 35 feet, courtesy of a storm system rolling down the Pacific coast and stirring up the seas.
3. Sierra snows this weekend
That same system will direct a narrow filament of Pacific moisture at California. Some of that moisture will be focused by the mountains, leading to 1 to 2 feet of snow in the higher elevations above 7,500 feet. At the highest mountain peaks, heavy snow will combine with winds between 50 and 100 mph to bring extreme whiteout conditions. The worst comes between Saturday and Sunday mornings.
Winter storm watches stretch from the Oregon Cascades to the Sierra Nevada northeast of Bakersfield, Calif. Visibilities could dip below 800 feet in the high Sierra between Madera and Tulare.
The snow in the Sierras — while disruptive for travelers — will be beneficial for water supplies. Amounts so far this season are just 30 to 40 percent of normal.
4. Increasing risk of a Midwest blizzard Tuesday into Wednesday
A new storm system will form somewhere in the southern Mississippi Valley around Tuesday. As it’s energized by a high-altitude disturbance (a pocket of cold air, low pressure and spin aloft), it will intensify quickly. That strengthening surface low should sweep up the Tennessee Valley and into the Midwest and toward the Great Lakes by Wednesday.
To its west, moisture pinwheeling into its cold side will drop a strip of snow, which could affect Kansas City, Mo.; St. Louis; Springfield, Ill.; and Indianapolis. Chicago and Detroit may end up on the edge of the zone of heaviest snow, so potential amounts there are uncertain. But wherever the jackpot ends up, as much as a foot isn’t out of the question.
“Current advice is to continue to monitor for updates, and have a winter preparedness plan in place,” cautioned the Weather Service office in Indianapolis.
The back side of the storm will also feature an influx of cold air that will ride in on strong winds gusting over 35 mph. Those winds will combine with falling snow to reduce visibilities below a quarter-mile, potentially for an extended period. That will make for blizzard conditions and the possibility of some power outages, especially in the eastern Great Lakes.
5. Severe storms and tornadoes in the South on Monday and Tuesday
On the warm side of that same system, severe thunderstorms are possible as humid air wafts north out of the Gulf of Mexico. Those thunderstorms will blossom vertically into an air mass characterized by wind shear, or a change of wind speed and/or direction with height. That could make some of them rotate, spawning tornadoes.
There’s also plenty of jet stream energy aloft, so thunderstorms will probably mix some momentum to the ground in the form of damaging straight-line wind gusts.
The Weather Service’s Storm Prediction Center has already drawn a zone to watch Monday from Houston to Mobile, Ala., and on Tuesday the threat will expand into the Southeast and northern Florida.
“The threat for supercells and short line segments capable of producing tornadoes, large hail, and damaging winds” is expected, the agency warned.
6. Flooding in the East on Tuesday and Wednesday
While generating snow in the Midwest and inciting severe storms in the South, this same storm will send a surge of mild air and moisture toward the Eastern Seaboard, bringing the potential for widespread heavy rainfall.
An enormous footprint of heavy rain is expected, with 1.5 to 2.5 inches from the Texas and Florida coastlines all the way to the Maine-Canada border. In the Northeast, the downpours will come on the heels of the weekend snowstorm and a waterlogged December. The combination of heavy rain and melting snow could well produce river flooding.
Meteorologist Ryan Maue estimated that 61 trillion gallons of water will fall over the Lower 48 in the next week — a volume “enormous even in summer.”
The storm could bear some similar characteristics to the one that blasted the Northeast the week before Christmas, which produced not only significant river flooding but also flooding along the coast and high winds that cut power to more than 800,000 customers.
7. A cold air outbreak in 8 or so days
Computer models are hinting at the possibility of a significant cold snap for the Western and Central United States in about eight to 10 days.
It appears that a large dip in the jet stream will allow bitter Arctic air to surge south, causing temperatures to drop well below normal. Models don’t yet agree on the severity of this potential cold air outbreak, nor on how far east the chill will extend.
As cold penetrates a growing area of the Lower 48, the potential for snow will increase toward the middle of the month in the southern tier, which has yet to experience much wintry weather this season.
Jason Samenow contributed to this report.
Amanda Smith is a dedicated U.S. correspondent with a passion for uncovering the stories that shape the nation. With a background in political science, she provides in-depth analysis and insightful commentary on domestic affairs, ensuring readers are well-informed about the latest developments across the United States.
