The ongoing humidity in northern Vietnam is expected to linger until April, the Vietnam News Agency quoted Nguyen Van Huong, an official from the National Center for Hydro-meteorological Forecasting, as saying. February is the middle of winter in northern Vietnam, so the cold spell still has a strong impact on the region, the weather expert elaborated. It ends when the northeast monsoon dominates the weather in northern provinces. The ongoing humidity in northern Vietnam is expected to linger until April, the Vietnam News Agency quoted Nguyen Van Huong, an official from the National Center for Hydro-meteorological Forecasting, as saying. February is the middle of winter in northern Vietnam, so the cold spell still has a strong impact on the region, the weather expert elaborated.