A unique weather phenomenon is expected to affect the UK on Christmas Day, as per the most recent forecast from the Met Office.
The Met Office anticipates unsettled weather conditions during the Christmas period, with low pressure likely located to the southwest of the UK and high pressure moving in from the east across northern regions.
For the period from December 21 to 30, the Met Office’s extended forecast predicts an easterly flow becoming established, with rainfall increasingly limited to southern or southwestern parts of the country. As Christmas approaches, high pressure is expected to dominate, bringing more dry and stable weather conditions.
Temperatures are likely to decrease compared to recent weeks, possibly falling close to or slightly below average in some areas. While extremely cold conditions are not expected at this time, the forecast mentions the possibility of a rare occurrence – freezing fog – becoming more widespread.
Freezing fog is described by the Met Office as an uncommon weather event that typically occurs in winter when temperatures are around freezing, skies are clear, and conditions are calm.
The formation of freezing fog is similar to regular fog, with the land cooling overnight under clear skies causing moisture in the air to condense into tiny water droplets, leading to fog. In freezing fog, these water droplets remain liquid despite being below freezing temperature, forming ice crystals known as rime when they freeze onto surfaces.
According to the Met Office, rime is a characteristic of freezing fog and is more commonly observed at higher elevations such as mountain tops, rather than at lower levels in the UK.
America’s National Weather Service highlights the dangers of freezing fog, warning that it can lead to the formation of black ice on roadways, which is difficult to see and poses a significant risk to drivers. The service advises caution when traveling in icy conditions and emphasizes the need for effective de-icing equipment on aircraft to prevent dangerous ice buildup.
