Commuters in the north have been warned to take care on the roads, including keeping an eye out for flying debris.
The storm, bringing wet as well as windy weather, will move across Scotland and the north of England throughout the morning, and a yellow warning remains in place until 3pm.
The Queen and the Duchess of Sussex’s first engagement together – opening Cheshire’s Mersey Gateway Bridge and the Storyhouse Theatre – may be hit by strong gusts, with winds of 60mph forecast for the north of England.
Winds have reached 100 mph at the very exposed Cairngorms in #Scotland. Here are some low level #wind gusts which are unseasonably high considering we're in June #StormHectorpic.twitter.com/2luXbnKMWG— Met Office (@metoffice) June 14, 2018
A “danger to life” weather alert was issued on Wednesday just days after forecasters said Britain could enjoy its hottest summer in 12 years.
Forecasters also warned of a risk to life in coastal areas from large waves and beach material being thrown onto sea fronts, as well as flying debris, power cuts and road and rail chaos.
Such stormy weather is “quite unusual for this time of year” forecaster Luke Miall said.
“The worst of the weather is going to be in the morning rush hour for most people,” he said.
“The storm is likely to clear to the north east around lunchtime or just after 1pm.”
Southern England and Wales are likely to escape the worst of the windy weather, he added.
❗ STORM HECTOR ❗— Traffic Scotland (@trafficscotland) June 14, 2018
💨 High Winds Warning - safety advice;
🚘Hold the steering wheel firmly
👀Watch for debris
🌀Overtaking: Sudden gusts as you clear vehicle
🚗Keep safe distance
🌲 🏠Park your vehicle away from trees & buildings#BeSafe ♥ pic.twitter.com/eCaTCRfLsg