Deadly wildfires have burnt across South Korea's southeast since last weekend, claiming the lives of at least 28 people and displacing nearly 40,000.

At least 28 people have lost their lives to the fire and more than 35,000 hectares of forest have burnt, displacing nearly 40,000 people from their homes. Officials on the ground are reporting this as the deadliest and largest wildfire since the Korea Forest Service started keeping records in 1987.

The wildfires started last weekend, March 22 and 23, about 150 kilometres southeast of Seoul, in the province of Gyeongsangbuk-do. Hot and very dry westerly winds fanned the blaze to the east between Saturday and Wednesday. As seen in the video below, the smoke plumes from the fire are propagated eastward by the winds.

Video: Satellite imagery between Monday, March 24, and Wednesday, March 26, over South Korea showing the masses of smoke from the wildfires in the southeast of the country.

As seen in the final frames of the video above, the smoke makes a turn to the north on Wednesday as a cooler, more humid southerly wind brings some relief to the firefighting effort. These conditions mostly persisted on Thursday and into Friday with a few scattered showers crossing the region with a cold front.

Much colder conditions are forecast over the weekend, with nights dropping below 0°C, as cold air moves in behind the front. Even with the colder temperatures, winds will be very dry and gusty, descending from the Tibetan Plateau. Dew point temperatures, a representation of the moisture in the air, will drop from the mid-teens on Thursday afternoon, down to around -20°C on Friday afternoon and on Saturday. This very dry air will combine with gusty westerly winds of around 50-60km/h in the afternoons, reaching up to 70km/h on Saturday, as seen in the image below.

Image: Forecast wind gusts at around 3pm KST on Saturday, March 29.

The very dry and gusty winds will make it difficult to contain ongoing fires, with flames and embers pushing eastward. Firefighters in the region are working hard to contain the fires ahead of this weekend, protecting people, homes, businesses and UNESCO-listed temples in the region.

A high pressure ridge should strengthen over the southern Korea Peninsula from next week, bringing calmer winds and gradually warming temperatures.