The Met Office warnings follow the death of an elderly man who was killed as winds rose to more than 100mph across the UK.
The man, in his 70s, was trying to move a tree near Chippenham, in Wiltshire, which had brought down power cables.
Gusts of up to 108mph hit Aberdaron on the Lyn Peninsula in Wales over the past 24 hours, while winds of 96mph were recorded off the south coast of England.
The Met Office has also issued yellow warnings for snow, wind and ice across many parts of the UK on Thursday.
Winds of up to 70mph are expected to strike areas in the South West and the Midlands, with North Wales, Northern Ireland and northern England also due to be battered by high winds.
Snowfall has been predicted for elevated regions in Scotland.
The Environment Agency has 14 severe flood warnings – meaning there is a danger to life – in place for the South East, covering regions close to the River Thames.
Two further severe flood warnings are in place for the Somerset Levels.
There are around 400 flood warnings and alerts in place for the rest of the UK, meaning people in the affected areas are urged to take immediate action or to be prepared.
Prime Minister David Cameron is expected to cut short his duties at an international conference to focus on the response to the flooding.
He had been due to speak at the a conference in London on the illegal wildlife trade, alongside the Prince of Wales and Duke of Cambridge.
The new Cabinet committee on flood recovery is also expected to meet, replacing a scheduled meeting of the full Cabinet.
Another storm is due to strike Britain on Friday, bringing the risk of further flooding to regions that have struggled with heavy rainfall and been under water since December.
The inclement weather has caused travel chaos, with Virgin Trains advising customers that “some services” will be affected this morning due to disruption.
On the North Yorkshire moors, an East Coast train was held up for several hours on Wednesday due to a power cut.
Passenger Antonia Goddard told Sky News: “We’ve been stuck here for a few hours now waiting for rescue.
“We were told there was no power for the train. We’ve been on emergency lights and there’s no heating.”
Hurricane-force winds also left more than 190,000 customers without power in Ireland.
The outage was the largest in the country for more than 15 years, with more than 2,000 separate faults across the network.
At its peak, the outage affected more than a quarter of a million customers.
Energy Networks Association said 80,000 people in the UK remained without power despite 145,000 people being reconnected following storm damage.
Those still cut off included 5,000 in the North East and Yorkshire, 5,000 in the North West, 3,650 in the south and 10,500 in Wales.
The Ministry of Defence (MoD) said more than 2,000 military personnel were on “high-readiness” to respond to requests in flood-affected areas.
Major General Patrick Sanders, assistant chief of the defence staff, said troops were providing help with resilience, relief and additional manpower for what he described as an “almost unparalleled” natural crisis.
“There’s more that we can do and we want to do more wherever we can make a difference, so please use us, that’s what we’re here for,” he said.
Meanwhile, officers from Greater Manchester Police took more than 1,700 calls in seven hours yesterday as severe weather hit the region.