The La Nina phenomenon has officially returned and begun to strongly affect global weather. In the US, meteorologists predict that this winter will be colder and foggier than usual in the Northern region, while the Southern region will be dry and warm.
According to the US National Oceanic and Atmospheric Administration (NOAA), the 2025-2026 winter will have below-average temperatures in the Northwest and Midwest regions of the US, with higher than usual rainfall and snowfall.
Although it is not possible to specifically determine the level of snowfall, this is considered the "perfect treatment" for a harsh winter - a sign commonly seen in La Nina years.
The FOX Forecast Center said 170 million Americans in 35 states will see a first look at winter next week as temperatures drop and snowfall is possible.
During La Nina years, the northeast and New England often experience Noreaster (seas) storms - a type of strong winter storm, carrying strong winds and heavy snow.
Since the beginning of the fall, the US East Coast has recorded a number of coastal storms, signaling a series of cold days ahead. In high mountain ranges such as the Rockies, Cascade and Sierra Nevada, the snow has fallen white; even Temple Mountain in North Carolina welcomed the first snowfall of the season.
NOAA forecasts the US could transition to a neutral ENSO state around January 2026 a time when snowfall in the northeast typically increases sharply in similar climate cycles to before.
The impact of La Nina is not limited to North America. With the characteristics of cooling the Pacific Ocean's surface, this phenomenon often causes cold air masses from Siberia (Russia) to flow into East Asia more strongly and deeper, leading to severe cold spells in Northern Vietnam.
According to the Vietnam Center for Hydro-Meteorological Forecasting, the probability of La Nina extending into early 2026 is quite high. This winter will be colder than other winters in recent years, warning of possible snowfall and ice.
Especially in the last month of 2025 and the first two months of 2026, strong cold air waves are forecast to appear, causing widespread cold spells in the North and North Central regions. The number of severe cold spells is likely to be approximately the average of many years.
During the cold spells, there is a high risk of extreme weather phenomena such as frost, ice, and even snowfall in the highlands of the northern mountainous provinces.
