The second named storm of the season will affect Wales and much of England on Friday, with yellow “be aware” warnings in place for both wind and rain.
Bronagh is likely to bring disruption during the morning rush hour due to the possibility of fallen trees, and the Met Office is also warning of flying debris posing a danger to life.
High winds also threaten to cut power, damage buildings, blow off roof tiles and trigger large waves on the coasts.
Up to 10cm of rain is expected to fall across high ground in Wales and Cumbria, with Bronagh expected to be at its peak in the early hours of the morning as it moves across the Midlands and the South East.
More than 5.6cm of rain was recorded in Sennybridge, Wales, on Thursday.
The unsettled weather, which also brings the threat of flooding, is due to last the rest of the week and is caused by a jet stream from Canada, the Met Office said.
The yellow warnings for wind are in place until 9am on Friday for the Midlands, the East, the South East, London, the North East, North West, South West, Yorkshire and Humber, and all of Wales.
Sky News weather presenter Isobel Lang said: “Heavy rain will become fairly extensive, bringing the risk of local flooding. Southern Ireland, Wales and North West England look most at risk.
“The rain will push further north during the afternoon, while the winds strengthen in the south with some very gusty, squally conditions in and around the downpours.
“Gusts will be in the region of 50mph, perhaps nearer 60mph around exposed coasts, with a small chance of stronger winds across eastern England during tonight and the early hours of Friday.”
Two people were killed, tens of thousands of people were left without power and transport networks ground to a halt on Wednesday as Storm Ali brought winds of up to 102.2mph.
A Swiss tourist in her 50s died in Claddaghduff, Co Galway, on Ireland’s west coast when her caravan was blown off a cliff. She had only arrived in the area hours before she was killed.
A man, aged in his 20s, who was working on behalf of public utility Northern Ireland Water in Slieve Gullion Forest Park, in County Armagh, died after he was hit by a falling tree.
There is the chance of a third storm later this weekend, which is currently below storm-naming criteria but is set to bring heavy rain and potentially very windy weather to southern Britain.