The Thames Barrier has reopened after shutting earlier due to high waters.
Further storms are expected in the next 24 hours.
The #ThamesBarrier is now open. We may have further closures over the next few days as the flow upstream remains high.
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Mayor of London Sadiq Khan is backing the scheme.
A spokesperson said the lightning strikes had left the "aircraft fuelling system unavailable."
Nearly 1,000 properties have been left without power, and road users have been warned of potentially hazardous conditions.