Only about a quarter of the Earth’s tropical cyclones form in the Southern Hemisphere. When these storms have sustained winds of 74 m.p.h. or greater, they would be called hurricanes in the Atlantic, but here, they are called cyclones. The only other difference is that, in the Southern Hemisphere, cyclones spin clockwise (hurricanes spin counterclockwise). Cyclones can strike eastern Africa, primarily Madagascar, as well as the western, northern and eastern coasts of Australia and surrounding island nations. The season here runs opposite the rest of the world, typically beginning in late October and running through May. Peaks in activity vary depending on the region, but normally, activity is highest in late February and early March. Sources and notes Tracking map Tracking data is from the National Hurricane Center. The map shows probabilities of at least 5 percent. The forecast is for up to five days, with that time span starting up to three hours before the reported time that the storm reaches its latest location. Wind speed probability data is not available north of 60.25 degrees north latitude. Wind arrivals table Arrival times are generated from a New York Times analysis of National Hurricane Center data. Geographic locations use data from the U.S. Census Bureau and Natural Earth. Time zones are based on Google. The table shows predicted arrival times of sustained, damaging winds of 58 m.p.h. or more for select cities with a chance of such winds reaching them. If damaging winds reach a location, there is no more than a 10 percent chance that they will arrive before the “earliest reasonable” time and a 50 percent chance they will arrive before the “most likely” time. Radar map Radar imagery is from the National Oceanic and Atmospheric Administration via Iowa State University. These mosaics are generated by combining individual radar stations that comprise the NEXRAD network. Storm surge map Storm surge data is from the National Hurricane Center. Forecasts only include the United States Gulf and Atlantic coasts, Puerto Rico, and the U.S. Virgin Islands. The actual areas that could become flooded may differ from the areas shown on this map. This map accounts for tides, but not waves and not flooding caused by rainfall. The map also includes intertidal areas, which routinely flood during typical high tides. Satellite map Imagery is from the National Oceanic and Atmospheric Administration and Japanese Meteorological Agency via the Cooperative Institute for Research in the Atmosphere. Precipitation map Data for multi-day forecasts or observed rainfall totals are from the National Weather Service. The 1-day forecast is from the National Oceanic and Atmospheric Administration.

Firefighters on Monday were working to contain more than 170 wildfires in North and South Carolina that have prompted evacuations, officials said. Heavy smoke blanketed the Carolina Forest area, a community just west of Myrtle Beach where the largest fire raged across 1,600 acres, and visibility in the area was “very low,” the Horry County Fire Rescue said on Monday. The Carolina Forest fire was 30 percent contained, according to the South Carolina Forestry Commission. Those who had evacuated from Carolina Forest were authorized to return home on Sunday, but officials warned residents to stay vigilant amid dry and windy conditions. South Carolina’s governor, Henry McMaster, declared a state of emergency on Sunday and said that a statewide burn ban would remain in effect indefinitely. The South Carolina Forestry Commission was dropping water from airplanes to battle the blaze. An air-quality alert warned residents of Horry County, which includes Myrtle Beach, to stay indoors on Monday, because smoke and concentrations of dust and soot may reach or exceed unhealthy levels, the South Carolina Department of Environmental Services said. Julinna Oxley, a philosophy professor at Coastal Carolina University, said she and her two teenagers and two cats evacuated from their home in Carolina Forest on Sunday night as the air quality became unbearable. “The air purifiers just could not keep up with the amount of smoke that was in the house,” she said. “You could literally see it.” Ms. Oxley said she has evacuated many times in the past because of possible hurricanes, but this was the first time she had done so because of a wildfire. “With a hurricane, you think even if you get hit, you’re going to go back and you’re going to have something,” she said. But with a fire, if a fire hits your house, all of your stuff is gone.” She packed her car with items that were irreplaceable and drove to her parents’ house in the next town over. Video posted on social media from Sunday morning showed firefighters battling flames near houses. But no injuries have been reported and no buildings have been lost, according to Horry County officials. Another fire in Horry County that burned about 800 acres was 80 percent contained as of Sunday afternoon, the Forestry Commission said on social media. Rain showers on Wednesday could help with containment, the Environmental Services Department said in its statement on Monday. In North Carolina, a brush fire in the mountains threatened Tryon and Saluda, small communities in the Blue Ridge Mountains about 40 miles south of Asheville. The fire had burned nearly 500 acres and was 30 percent contained as of Monday morning, according to Polk County Emergency Management, and crews were reinforcing fire lines. The fire was caused by a downed power line and quickly spread up a mountain, threatening several buildings, according to Saluda Fire and Rescue. The fires ignited while a large portion of the southeastern United States was under a red-flag warning, an alert from the National Weather Service. The agency said on Monday that a “critical to extreme” fire weather danger across much of the Southern High Plains would continue through the early to middle part of the week. The fires also affected Georgia, where the forestry commission said on social media that 137 wildfires had burned 2,390 acres on Saturday. Conditions were “slightly better” on Sunday, the agency said, and it cautioned residents against doing anything that could spark a fire. Gusty winds, dry air and afternoon high temperatures in the low 70s helped fuel the rapid spread of the flames. South Carolina also had unusually low rainfall in February, and the vegetation is dry. Heather Budner, who lives in Carolina Forest, said she woke up Monday morning and felt a scratchiness in her throat because of all the smoke, as if she had spent the night next to a bonfire. “It’s very unsettling to wake up inside your house feeling like you’re outside camping,” she said. She said she would consider evacuating and sleeping elsewhere on Monday night if conditions did not improve, but hoped that the rising temperature and a slight breeze would help clear the smoke away. Myrtle Beach has recorded 2.3 inches of rain since Jan. 1, far less than the 6.30 inches of rain that is considered normal for this time of year. North Carolina was a bit wetter last month, though it also received below-average rainfall.

Waterfalls that had dwindled during an unusually dry January roared back to life this week in Oregon’s largest state park after days of heavy rain, delighting visitors eager to catch a glimpse of the cascades. The popular Trail of Ten Falls at the park, Silver Falls State Park, near Salem, sends hikers on a meandering, 7.2-mile journey through a lush forest. The trail’s 10 thunderous plunges were supercharged this week as water poured into the Cascade Mountains, and they were joined by a dozen new waterfalls that have popped up. “There a lot of ephemeral waterfalls that just showed up after the rain,” said Matt Palmquist, a ranger at the park. “It’s like walking through an enchanted forest.” Silver Falls State Park draws over a million visitors annually to its more than 9,000 acres in the foothills of the Cascade Mountains. It’s an especially rainy corner of the Pacific Northwest as storms unleash heavy rain when they move up and over the mountain range. The park records about 80 inches of rain annually on average, Mr. Palmquist said. Salem, only 25 miles northwest, gets half that per year. This year, though, has been drier than usual across the Pacific Northwest, with few storms in January. “Most of the rain happened early in the month, and then we were basically dry,” said Hannah Chandler-Cooley, a meteorologist with the National Weather Service office in Portland, Ore. “We had some good stretches of sunshine in there.” February finally brought significant rain to the Pacific Northwest with a series of back-to-back storms. Several areas near the park broke or nearly broke same-day rainfall records over the weekend when an atmospheric river hammered the region. A second storm hit on Monday and brought more rain as well as strong winds that knocked out power to tens of thousands of people in Oregon and Washington. Silverton, a town close to the park, recorded only 3.26 inches of rain last month compared with the 6.70 inches it measures on average in January. It has recorded 5.6 inches of rain since Feb. 1. While most visitors go to the park in summer, Mr. Palmquist said winter was the best season because that’s when the waterfalls have the biggest flows. Many of the country’s biggest waterfalls, such as those in Yosemite, peak after the snow melts in spring, but the falls in Silver Falls State Park are fed by winter rains, because the park sits at a lower elevation, about 1,300 feet. In winter, after a storm like the one last weekend, the cascades of water grow so large that anyone who wants to take in the park’s most popular experience — that is, standing behind a waterfall — is bound to get wet. Of the park’s 10 big waterfalls, there are four, including the 177-foot-tall South Falls, that visitors can walk behind. “After these big rains, it’s like walking through a carwash,” Mr. Palmquist said. The big, gushing waterfalls make for spectacular photos and images, and videos of them appear all over social media. The ephemeral falls, the slight flows of water running down rocky hillsides blanketed in moss, feel like a secret. “They’re really difficult to photograph,” said Matt Vahle, a photographer based in California. “They’re smaller.” In some cases the fleeting falls are too far from the trail to capture without a special lens. Others are nearly right on top of you. “You’d be walking down the trail and you could stick your hand out and there would be a 15-foot waterfall right there,” Mr. Vahle said. Mr. Vahle visited the park Saturday during a photography trip to Oregon when the rain was pouring down. Walking along the Trail of Ten Falls, he saw the ephemeral falls forming right before his eyes. “These little falls popped up everywhere,” he said. “They were coming up out of the rocks. There’s a bridge you cross, and when you look out over the bridge you can see three or four of these little mini-waterfalls coming out.”

Extreme heat can be particularly dangerous for older people, putting them at increased risk for heat stroke and death. But could it also affect how their DNA functions, and accelerate the aging process itself? A new study, published Wednesday in the journal Science Advances, suggests it could. The analysis of over 3,600 older adults in the United States found that those living in neighborhoods prone to extreme heat — classified as 90 degrees or above — showed more accelerated aging at a molecular level compared with those in areas less prone to extreme heat. The findings suggest that heat waves and rising temperatures from climate change could be chemically modifying people’s DNA and speeding up their biological aging. The study authors estimated that a person living in an area that reached 90 degrees or above for 140 days or more in a year could age up to 14 months faster than someone in an area with fewer than 10 extreme heat days a year. To conduct the study, the researchers analyzed three biomarker aging estimates, known as epigenetic clocks, which were derived from blood samples of people age 56 and older as part of a separate national population study. They then looked at these age estimates alongside six years of daily climate data, comparing them across geographies. Advertisement SKIP ADVERTISEMENT Epigenetic clocks measure biological changes that could predict the future risk of disease or death associated with older age. They estimate “how well the body is functioning at the molecular and the cellular level,” said Eun Young Choi, a postdoctoral associate at the U.S.C. Leonard Davis School of Gerontology and a co-author on the paper. While DNA is fixed at birth, external factors like stress or pollution can trigger molecular changes that turn genes on and off and affect how they operate. “DNA is like a blueprint,” Dr. Choi said, but these epigenetic changes are like the “switchboard that controls which part of the blueprint gets activated.” This is the first population-level analysis to establish a connection between heat exposure and epigenetic aging in humans, building on separate research finding similar changes in fish, mice and guinea pigs. “It’s important, suggestive work” that could offer a biological explanation for geographic health trends, said Nancy Krieger, a professor of social epidemiology at Harvard T.H. Chan School of Public Health who was not involved in the study. Many of the places in the U.S. that the study found to have the most extremely hot days “are also some of the states that have the worst health profiles,” she said. But, Dr. Krieger added, heat likely isn’t the only factor. And the authors emphasized there’s not enough data to definitively conclude that heat exposure caused the acceleration in aging — only that the two appear linked. In addition, the data they analyzed didn’t contain details about individuals’ lifestyles, such as whether they had access to air conditioning or spent the majority of time indoors. There’s also some debate among scientists about whether epigenetic clocks are the best measure for aging, said Rachel Morello-Frosch, an environmental health scientist at the University of California, Berkeley. How to best measure biomarkers, and how to use them to predict future health, is an “evolving space in the scientific field,” she said. Epigenetic changes aren’t necessarily bad, either, and the study doesn’t clarify whether they could reflect positive adaptations to heat instead of negative ones, said Greg Wellenius, an environmental epidemiologist at Boston University School of Public Health. People in hotter areas may have acclimatized to the heat, potentially by spending more time indoors, he said. But just “indicating that there is a quantifiable change at the cellular level” is a step toward understanding heat’s effect on the body, he said. Experts say there are still many questions left to answer: How might things like air conditioning affect epigenetic aging? Can short visits to hotter areas cause you to age faster? Can moving away from hotter areas reverse it? Because the analysis was based on a single blood sample from each subject, “we don’t really have that kind of longitudinal data” yet, said Jennifer Ailshire, a professor of gerontology and sociology at the U.S.C. Leonard Davis School of Gerontology and the other author of the study. This study may open the door to future research into how interventions, like air conditioning or more shade, could stave off the adverse effects of aging, said Mariana Arcaya, a professor of urban planning and public health at the Massachusetts Institute of Technology. “Right now, the literature is very focused on, ‘Can you survive in extreme heat without medical intervention?’” she said. This study, in contrast, suggests that even if people aren’t at immediate risk of health crises or death because of the heat, “there may still be an effect.”

Astute skywatchers may have already seen the striking line of planets across the night sky in January. This week Mercury joins the queue. Now every other world in our solar system will be visible among the stars at the same time — if you know where to look. According to Gerard van Belle, director of science at Lowell Observatory in Arizona, an alignment of seven planets is neither mystical nor particularly rare. “On the scale of supermoon to death asteroid, this is more a supermoon sort of thing,” Dr. van Belle said. Still, the planetary parade, as the event is colloquially named, “makes for a very nice excuse to go outside at night, maybe with a glass of wine, and enjoy the night sky.” Why are the planets aligned? Whenever planets are visible in the night sky, they always appear roughly along the same line. This path, known as the ecliptic, is the same one that the sun travels along during the year. This happens because the planets orbit around the sun in the same plane. Dr. van Belle likened the configuration to a vinyl record: The sun is in the center, and the grooves are the orbits of the planets around it. Our point of view from Earth, then, is along one of those grooves, “looking out along the platter,” he said. This week, the planets are configured in such a way that all of them will be present in the sky at dusk from mostly anywhere on Earth. Around the end of the month, Saturn will slip below the horizon and into daytime skies, ending the seven-planet parade. But stargazers will get another chance to see a planetary alignment in August, when several of our celestial neighbors will be visible in morning skies. How can I see the parade? Only a handful of the planets can be seen with the unaided eye, and the best evening to catch them all may vary by location. Astronomers recommend using a software program like Stellarium to figure out when and where to look. To see the parade, find a dark place with a clear view of the western horizon at nightfall. Mercury and Saturn will be low in the sky, brushing past each other in the fading glow of the evening sun, which will make the pair difficult to spot. Trace that line of sight higher to find Venus, the most brilliant planet in the sky. “Venus, you cannot miss,” said Thomas Willmitch, director of the planetarium at Illinois State University. “You could be in a haze under streetlights, and there’s Venus, shining like a beacon to the west.” Even higher up, almost directly overhead, will be Jupiter, sparkling at about one-tenth the brightness of Venus. The string of planets ends in the eastern sky with Mars, easily discernible because of its pinkish tone. The planet is a few weeks past a close encounter with Earth, making it appear bigger than usual. According to Mr. Willmitch, this proximity has also cast the Red Planet in somewhat of a golden hue. The other two planets are too far away to be seen without binoculars or a telescope. Uranus is about two fists west of Jupiter, Mr. Willmitch said, while Neptune is hiding between Venus and the western horizon. But even if you can’t catch them all, Mr. Willmitch advised layering up and looking up anyway. “The sky is really beautiful in winter,” he said. “It’s a great time to go out and do some stargazing.”

An atmospheric river of moisture was draped across the Pacific Northwest on Saturday and will deliver breezy winds and drenching rains to Washington and Oregon into Sunday. A second quick-hitting system is expected to sweep the region Monday into Tuesday and bring more rain and potentially stronger winds. During the back-to-back storms, heavy rain could cause flooding and strong winds could knock out power and down trees. Forecasters are calling these typical winter storms, although this winter has been anything but typical for the region. Washington and Oregon are famously wet and gray in winter, and a bulk of their precipitation comes from these sorts of storms. But this year, both states saw unusual dry stretches in January. Advertisement SKIP ADVERTISEMENT “We had weeks where it was sunny every day,” said Anna Ruhl, a meteorologist with the National Weather Service in Portland, Ore. Between Friday and Tuesday, Seattle is expected to record two and a half inches of rain, and Portland could pick up about two inches. Those amounts are in stark contrast to the rainfall totals from January. The Portland International Airport recorded a little less than three inches last month, down from the five it typically records in January. The discrepancy is more extreme in Seattle, which measured 1.92 inches of rain last month, compared with the 5.78 inches in a typical January. February was already on track to make up some of the deficit. A storm brought rain and snow to the region earlier this week, and the approaching atmospheric river is predicted to be strong, bringing a bigger dose of precipitation. Atmospheric rivers are ribbons of water vapor that stretch for thousands of miles and are carried through the sky by powerful winds. Upon hitting land, the atmospheric rivers can release heavy rain, especially as they move up and over mountains. This system will deliver multiple waves of moisture. As there often is with this type of storm, “there remains uncertainty as to the rainfall amounts” the region is expected to see, said Jacob DeFlitch, a meteorologist with the Weather Service office in Seattle. He warned that the rain would likely lead to “significant rises” on the region’s rivers, prompting a risk of flooding. Some of the highest precipitation totals are expected over the Olympic Peninsula in Washington, where over six inches of rain could fall at the coast and over 10 inches of precipitation in the mountains from Friday to Tuesday. Snow is expected to mainly fall at elevations above 7,000 to 8,000 feet, but more rain than snow is expected in the mountains with this system, which is warm and pulling in moisture from the subtropics, as is usual with atmospheric rivers. Rain is likely to fall on snow that’s already on the ground, and could trigger snow melt and water rushing down into streams and rivers.Rivers are forecast to swell, with several expected to get close to flood stage. The Skokomish River, which flows from the Cascade Mountains to Puget Sound in Washington, is poised to spill its banks over the weekend. The flood forecast for rivers is constantly changing, and people should turn to their local Weather Service offices for the latest information. To the north, the storm will affect British Columbia, with Vancouver Island expected to record seven to 10 inches of rain and Vancouver a little less, said Chad Hecht, a meteorologist with the Center for Western Weather and Water Extremes at the University of California, San Diego. To the south, the system will brush far Northern California, with locations across Del Norte County poised to get up to five inches of rain. Mr. Hecht said that anyone living between British Columbia and far Northern California should prepare for days of rain. “You could have a multiday event, maybe 72 hours-plus for some locations,” Mr. Hecht said. “It’s going to be a wet couple of days.” The big, wet weekend storm will be followed by a second “more compact” system that’s not an atmospheric river, Mr. DeFlitch said. Advertisement SKIP ADVERTISEMENT “It may be strengthening as it approaches land, and that could result in strong winds,” he said. “There’s still uncertainty in the forecast.”

A backcountry snowboarder was killed in an avalanche on Thursday in a remote part of southwestern Colorado, the fourth person to die in a mountain slide this week in the western United States following several winter storms. The Colorado Avalanche Information Center said that the victim was traversing a terrain feature known as The Nose, near Silverton, Colo., when the person got caught in the avalanche. A skier who was with the snowboarder escaped the avalanche, the authorities said. Emergency responders used a helicopter to try to rescue the snowboarder, but the person did not survive, the center said. Rescuers were alerted about the avalanche by the staff from a nearby backcountry hut. The avalanche added to what has been a deadly week in the West. On Monday, two skiers were caught in an avalanche in the Cascade Mountains in Oregon, one that occurred at a height of 6,700 feet on a south-facing slope. Their bodies were recovered on Tuesday. Advertisement SKIP ADVERTISEMENT Also on Monday, an avalanche claimed the life of a backcountry skier in California near Lake Tahoe. The Sierra Avalanche Center said that the skier was traveling alone when he triggered the avalanche, which carried him downslope over rocks and through trees. The victim was buried beneath more than four feet of snow against a tree, the center said.

Along the sparkling coast of Southern California, a string of landslides creeping toward the sea has transformed the wealthy community of Rancho Palos Verdes into a disaster zone. New data from a NASA plane shows the widening threat of these slow-moving landslides, which have destabilized homes, businesses, and infrastructure like roads and utilities. Researchers at NASA’s Jet Propulsion Laboratory documented how the landslides have pushed westward, almost doubling in area since the state mapped them in 2007. The landslides have also sped up in recent years. A month of aerial radar images taken by NASA in the fall revealed how land in the Palos Verdes Peninsula slid toward the ocean by as much as four inches each week between mid-September and mid-October. Before that, a city report showed more than a foot of weekly movement in July and August.The mass of slides in Los Angeles County, known as the Greater Portuguese Bend Landslide Complex, reactivated in 1956 after road construction destabilized the once-dormant slope. For decades, it slid just a few inches every year. But heavy rain in 2023 and early 2024 accelerated that movement, leading Gov. Gavin Newsom to declare a state of emergency, citing “conditions of extreme peril to the safety of persons and property.” Homes in Rancho Palos Verdes began collapsing in June and August of 2023. Streets have fissured. Walls have shifted and floors have cracked open to reveal the dynamic earth below. A downed power line related to the slides started a small brush fire in August. A $42 million buyout program helps property owners voluntarily sell and relocate, but homeowner insurance policies do not typically cover landslides. Mitigating such a disaster is extremely expensive. By the end of this fiscal year, the city said it will have spent more than $35 million, almost 90 percent of its general fund operations budget, on addressing the landslide. That includes the installation of 11 wells that have worked to pump out 145 million gallons of groundwater that could further destabilize the slope. The investment has yielded results: The landslide slowed by about 3 percent on average between December and February thanks to the wells and a lack of rain, the city said. Slow-moving slides are common around the world, and especially in California, where several hundred have been mapped in coastal mountain ranges. Normally moving at a sluggish pace, these slides can grind nearly to a halt during the dry summer months before a wet winter makes them crawl again. But last summer, the landslide complex in Rancho Palos Verdes exhibited strange behavior when it failed to slow. The best guess for why has to do with a very wet 2023, said Alexander Handwerger, a research scientist at the NASA Jet Propulsion Laboratory who has studied the behavior of slow-moving landslides for well over a decade. Typically triggered tens of meters underground, they remain an ongoing area of research. “Of all the things we know,” Dr. Handwerger said, “we know the least about what’s happening under the ground.” Last week, other parts of Los Angeles County faced additional landslides, ones that move quickly, running at meters per second instead of centimeters per week. The National Weather Service in Los Angeles issued warnings for post-fire debris flows — a tangle of mud, rocks and trees that start on burn scars — ahead of heavy rainfall on Thursday. Los Angeles neighborhoods scorched by wildfires like the Eaton and Palisades fires last month faced some of the greatest dangers as those flows hit business and homes in Southern California. But slower-moving landslides, like the ones in Rancho Palos Verdes, are more predictable. They ooze rather than race. They typically need a season of rain, rather than a single storm, to accelerate. And it’s extremely rare for them to suddenly collapse or slide in a catastrophic way. It’s unclear what triggers that kind of sudden catastrophe, said Luke McGuire, an associate professor in geomorphology at the University of Arizona. He pointed to one of the few known examples of such an event, in 2017, when the Mud Creek Landslide in Big Sur gave way after eight years of stable sliding. More than 65 feet of rocks and dirt covered a quarter-mile of Highway 1, the scenic drive winding along the California coast. Experts say that the city of Rancho Palos Verdes probably will not experience that kind of sudden event. “You can never say never, but the likelihood that this would go into a catastrophic movement phase is quite low,” said Dave Petley, a landslide expert who collects global landslide data for the American Geophysical Union. “It’s likely it’ll continue to cause substantial property damage, but the risk of the thing suddenly sliding into the sea and taking everyone with it is not particularly high.” A 2019 Nature study by Dr. Handwerger showed that the Mud Creek Landslide could have been triggered by a shift from drought to record rainfall. In a warming world, an increase in extreme rain events could cause more landslides to quicken, according to the study. More precipitation could also cause more landslides to emerge from hibernation into slow-moving slides. “Rainfall under climate change can wake a landslide back up,” Dr. Petley said, adding that a vast number of dormant landslides with this potential exist across the globe.

An intense cold front is sweeping into the Mediterranean this week, bringing a sharp temperature drop and snow. The weather system, named Coral by the Greek National Weather Service, is expected to unleash two waves of wintry conditions that are expected to last from Wednesday through next Monday. The weather service issued an emergency weather alert on Tuesday warning residents to take precautions as daily activities, especially those done outdoors, could be affected. “The drop in temperature will be gradual,” the weather service said, with forecasters expecting temperatures to fall below typical levels by nearly 20 degrees Fahrenheit in northern and eastern Greece. The lowest temperatures are expected by the weekend, as cold northerly winds surge to the south. By Friday, ahead of a second wave of cold, Macedonia, Thrace and the islands of the northern Aegean are forecast to experience temperatures ranging between 19 and 45 degrees Fahrenheit (minus 7 to 7 degrees Celsius), while Thessaly, central and eastern Sterea, eastern Peloponnese and the island of Euboea will range between 28 and 48 degrees Fahrenheit (minus 2 and 9 degrees Celsius). Advertisement SKIP ADVERTISEMENT The mean February temperature for Greece is between 45 and 54 degrees Fahrenheit (7 and 12 degrees Celsius), according to weather service climate data. The cold air will affect other areas in the eastern Mediterranean and the Middle East as well, including Turkey and Syria, where temperatures are also forecast to drop significantly below their seasonal average by the weekend. Snow is also forecast to come in from the north, mostly from over the mountains of Greece, but also reaching some lower elevations, and forecasters are closely monitoring whether snowfall will reach Athens and Attica. Parts of Turkey, Romania and Bulgaria are also expected to receive snow. The snow is being generated as brisk northerly winds pick up moisture while sweeping over the warm Black Sea. As these moisture-laden winds reach land on the other side, they release the snow, much like lake-effect snow. In addition to the snow, strong northerly winds reaching gale force (eight on the Beaufort scale) will batter the Aegean, where marine warnings have been issued. The Beaufort scale, which measures wind intensity from zero to 12, categorizes 12 as hurricane-force winds.In response to the cold weather, the Ministry for Climate Crisis and Civil Protection in Greece has ramped up emergency preparedness, with local authorities being put on high alert. Additional resources are being allocated to assist those in need. The Municipality of Athens has also placed critical services on 24-hour operations “for as long as necessary” starting Wednesday, providing accommodations, food and other essential care to homeless citizens to protect them from the low temperatures.

A sprawling storm was bringing powerful winds, snow and freezing conditions from the Midwest to the Northeast on Monday, causing power outages and disrupting travel as conditions were expected to worsen through the week. As one storm was moving away from New England — and was expected to continue producing strong, gusty winds across the Northeast and Great Lakes over the next couple of days — the next winter storm was hitting the Central Plains and Midwest on Monday. It was likely then moving to the Mid-Atlantic by Wednesday and the Northeast by Thursday. Millions were under extreme cold warnings, from the Upper Midwest and Plains down to Oklahoma and parts of Texas. High temperatures were expected to remain below freezing for many areas between central Texas and the southern Mid-Atlantic, the National Weather Service said. The lowest wind chills over the next few days are forecast from northeast Montana to North Dakota, where the Weather Service predicted it would feel as cold as 60 degrees below zero. Advertisement SKIP ADVERTISEMENT “This level of cold is life threatening and could shortly lead to frostbite and hypothermia,” the Weather Service said. By midweek, lows across much of the Northeast, Midwest, and parts of the southern Plains, including Oklahoma and northwest Texas, were expected to dip into the single digits. In North Dakota, Gov. Kelly Armstrong signed an executive order waiving service requirements for drivers of commercial vehicles hauling propane and other petroleum products that could be used for heating, his office said on Monday. At least 10 people died as a result of severe weather in the South over the weekend, which included flooding in parts of Tennessee and Kentucky. In some flooded areas, temperatures had already dropped below freezing, and would continue to drop, said David Roth, a meteorologist with the National Weather Service The floodwaters could become icy, slowing their retreat, Mr. Roth added, noting that the bitter conditions would persist through Friday. In southwest Detroit, where temperatures had already dropped to the single digits, a broken water main flooded roads and homes in the region, city officials said. Photos and videos posted to social media appeared to show residents being rescued by boat from icy waters that reached up to car windows. In Nebraska, a state trooper was killed in a car crash while responding to another crash, the Nebraska State Patrol said on social media. The crash was related to the severe weather, a representative from the State Patrol said. Further details were not immediately available on Monday. High wind warnings were in effect across the Northeast, from parts of Delaware to Northeastern Maine, until Monday evening. Gusts in Nantucket, Mass., had reached 52 miles per hour, and at least 40 m.p.h. in Provincetown, Mass., Newark, N.J., and in parts of Pennsylvania, Mr. Roth said. Blizzard warnings also remained in effect for the western slopes of the central Appalachian Mountains because of strong winds, although they were expected to taper off later on Monday. The American Avalanche Association and the U.S. Forest Service’s National Avalanche Center warned of a high risk of avalanche in some parts of Colorado, Wyoming and Utah, including near Salt Lake City. Winds on Sunday delivered gusts approaching or exceeding hurricane strength, including 76 m.p.h. gusts at Camp David, located about 1,841 feet in the Catoctin Mountains in northern Frederick County, Md., according to the Weather Service. Sustained hurricane force winds start at 74 m.p.h. Wind gusts of 71 m.p.h. were recorded at Atlantic City International Airport on Sunday, according to the Weather Service. At Ronald Reagan Washington National Airport, the winds were recorded up to 65 m.p.h., said Connor Belak, a meteorologist with the National Weather Service. One woman died in Philadelphia after a tree fell onto her vehicle on Sunday evening, the Philadelphia Police Department said. The high winds led to widespread power outages across much of the Mid-Atlantic, according to Poweroutage.us, which tracks power outages. Travel was largely back to normal on Monday after hundreds of flights were delayed or canceled in New York on Sunday, according to the airline tracking website FlightAware.