BEIJING, April 11 (Xinhua) -- Gale-force winds are sweeping across northern China and are expected to persist through Sunday, prompting authorities to implement measures to ensure public safety.Raging winds have already lashed regions including Inner Mongolia, Hebei, Beijing and Ningxia, driven by a powerful cold vortex moving southeast from Mongolia.The National Meteorological Center (NMC) said in an updated forecast that from 8 p.m. Friday to 8 p.m. Saturday, winds of up to force 13 (37.0-41.4 m/s) on the national wind scale will hit parts of Inner Mongolia, Shanxi, Hebei and Beijing.At 5 p.m. Friday, strong winds of 23.3 meters per second struck Yanqing District on the outskirts of Beijing, while scattered showers have already occurred and are expected to continue across most areas of the municipality by this evening, according to the Beijing Meteorological Service.The strongest winds will hit on Saturday, with temperature highs dropping to 14 degrees Celsius -- a 13-degree-Celsius decrease in temperature within a 24-hour period, the service said.On Friday afternoon, gusts reaching a maximum force of level 13 hit northwest China's Ningxia Hui Autonomous Region, causing severe sandstorms that are expected to impair visibility, according to the region's meteorological authorities.In northeast China's Liaoning Province, temperatures are expected to drop by as much as 12 degrees Celsius by Saturday. Over the weekend, some areas of the province will experience moderate rain turning to sleet, followed by heavy snowfall and blizzards, with extreme blizzards anticipated in certain mountainous areas, according to the provincial meteorological service.NMC also issued alerts for strong gales, snowstorms, sandstorms and rainstorms on Friday, which are expected to impact northern regions and parts of central China.The meteorological center has advised the public in affected regions to stay indoors and avoid lingering under tall buildings, billboards, temporary structures and trees when outdoors.In response, multiple tourist sites in regions including Beijing and Ningxia have announced temporary closures. High winds have also led to the postponement or cancellation of some performances in Tianjin, as well as the suspension of ferry services.Farmers in Liaoning have been advised to spray antifreeze agents to prevent frost damage to their fruit and to reinforce their greenhouses. The province also recommends conducting thorough inspections and maintenance of infrastructure, such as power lines and communication cables, to prevent damage or short circuits caused by severe weather conditions.Beijing's transportation authorities announced the suspension of certain bus routes passing through mountainous areas and some elevated rail services on Saturday.Over 14 train services in Beijing and surrounding areas will be temporarily suspended on Friday and Saturday to ensure safe operation, according to the China Railway Beijing Group Co., Ltd.The Beijing Capital International Airport has also warned that the strong winds may disrupt normal operations, potentially leading to flight delays or cancellations.The Chinese capital has postponed several sporting events, including marathons and football matches scheduled for the weekend, while residents are advised to avoid nonessential travel.