Police have warned that the threat posed by extremists has "evolved" as a range of new measures designed to protect the UK from terrorists was announced.
Most areas will have a dry day, and once overnight frost and fog lifts there'll be plenty of sunshine.
However, cloud will gradually thicken in the northwest bringing rain, some of which could be heavy, especially across western parts of Scotland.
A brisk wind will accompany the rain, but much lighter winds are expected across England and Wales.
Top temperature 9C (48F).
A British banker accused of killing two Indonesian women in Hong Kong has been declared fit to stand trial for their murders.
A judge ruled that Rurik Jutting, 29, was mentally fit to stand trial next year following two weeks of psychiatric examinations, the AFP news agency reported.
The bodies of Seneng Mujiasih and Sumarti Ningsih - reported to be sex workers - were found in his flat on November 1.
Mujiasih was found with knife wounds in the living room, before Ningsih's body was discovered hours later in a suitcase on the balcony.
Mr Jutting, a Cambridge University graduate, recently worked as a securities trader at Bank of America Merrill Lynch.
The case was adjourned until July.
A woman has been charged with the attempted murder of her newborn son who was allegedly abandoned in a drain.
The baby, who is only days old, was discovered inside the drain by a group of cyclists in a Sydney suburb on Sunday - five days after he was allegedly placed there.
He is said to be in a serious but stable condition at a children's hospital.
The 30-year-old woman is due to appear at Penrith Local Court on Friday.
Insurance companies will be banned from paying ransoms to terrorists to free British citizens, under new measures announced by the Home Secretary.
The Counter-Terrorism and Security Bill, being introduced to Parliament this week, will make clear it is an offence for firms to reimburse ransom payments, Theresa May said.
Mrs May, who will address a counter-terrorism event in London today, said it would help end the practice which "only put many more lives at risk".
The policy is part of a range of measures - including giving police more powers to seize internet data about suspected terrorists - to protect the UK from terrorists.