London is among the regions covered by the UK Health Security Agency’s (UKHSA) alert, which also applies to the East Midlands, West Midlands, South East, South West, East of England, and Yorkshire and the Humber.

The alert comes into force at 8pm today (December 28) and remains in place until 12pm on January 5 2026.

Temperatures are forecast to fall to between 4C and 6C in affected areas.

Health officials have warned of increased risks to vulnerable groups as a result.

Dr Agostinho Sousa, head of extreme events and health protection at the UKHSA, said: “As the colder weather sets in it is vital to check in on friends, family and neighbours that are most vulnerable.

“The forecasted temperatures can have a serious impact on the health of some people, leading to increased risk of heart attacks, strokes and chest infections, particularly for individuals over the age of 65 and those with pre-existing health conditions.”

The UKHSA said the cold conditions could trigger a rise in deaths, especially among older adults and those with existing health issues.

There may also be increased demand on health services and difficulties maintaining indoor temperatures at the advised 18°C, posing further risks to public health.

The alert comes as the UK enters the new year with colder weather expected to settle in during the opening days of 2026.

Met Office forecaster Dan Stroud said conditions are likely to get more unsettled as the new year begins.

Mr Stroud said: “We’re losing this sort of settled but chilly conditions, and bringing in something a little bit more showery with more wintry hazards in the forecast, particularly for the north of the country.”

While temperatures at the end of 2025 are not forecast to be especially low, around 7C or 8C, colder weather is expected to move in from New Year’s Day, particularly in regions covered by the yellow alert.

Courtesy of Harrow Times | Local News