At around 6 a.m. Monday, a thin layer of frost covered the wooden floor where the Fansipan symbol of the 3,147-meter-high mountain was located. The frost remained for around 30 minutes, before melting away under the sun.
Northern Vietnam regions are feeling the brunt of a mass of cold air, in combination with dry winds, causing temperatures to plunge to 10-12 degrees in mountainous areas, 13-15 degrees at the plains, and daytime temperatures at around 25-27 degrees, according to the National Center for Hydro-Meteorological Forecasting.
A high disparity between daytime and nighttime temperatures, and the fact that moisture level is below 50%, means the weather is dry.
This week, northern Vietnam is expected to be impacted by more cold waves while moisture levels remain low. Daytime temperatures are expected to rise by 2-3 degrees compared to last week, to 27-29 degrees. In some mountainous areas, frost can harm crops.
Ice and frost typically form when air temperatures drop below 4 degrees, and temperatures of the surfaces of objects, like plants and the ground, are at around zero degrees.