The Thames Barrier is in the process of being closed ahead of high tide. The process takes around 90 minutes.
We are just starting to close the #ThamesBarrier now. The falling radials are dropping into position.
Some parts of the UK are have seen the worst storm surge in 60 years, but we are not out of the danger yet.
A combination of factors are combining to make this storm surge particularly powerful.
Water levels around the UK could be higher than in the storm surge of 1953, but thanks to flood defences the impact is likely to be smaller.