As thunderstorms gather over London, Canadians watching the Met Office warning see a reminder of similar weather risks that can affect parts of southern Canada and the northern United States.
Met Office warning details
London remains under a Met Office yellow warning for thunderstorms as rain swept across the capital overnight.
Met Office weather maps show rain across the capital in the early hours bringing 8mm of rain in some places - but the capital so far appears to have avoided any thunderstorms.
Forecasters at the Met Office had predicted "a band of heavy showers and thunderstorms" hitting the capital on Wednesday morning and further showers, with further stormy weather hitting in the afternoon.
But current weather forecasts on the BBC and Met Office for Wednesday forecasts predict rain showers during parts of the day - but not thundery downpours. Rain is set to fall during morning rush hour.
A yellow warning for thunderstorms has been issued from 3am to 10pm on Wednesday across much of England including London and the South East, the Midlands, East Anglia, and parts of the North West, South West, as well as eastern parts of Wales.
The Met Office warned that showers and thunderstorms on Wednesday afternoon "may be intense", with 20-30mm rain falling in less than an hour and 40-50mm being possible in two to three hours in a few spots, leading to some surface water flooding.
In Canada, Environment Canada also issues yellow thunderstorm warnings for regions such as southern Ontario when similar conditions develop.
Canadian commuters are accustomed to adjusting travel plans during sudden downpours, much like Londoners facing potential train delays.
The United States' National Weather Service monitors comparable storm systems across the Great Lakes, highlighting the shared risk of flash flooding across North America.
Potential impacts in London
On Tuesday afternoon Sir Sadiq Khan put London on alert for flash floods as thunderstorms were forecast to erupt over the city.
The London Mayor urged Londoners to prepare for possible torrential downpours.
"From 3am, London is at risk of severe flash floods," he posted on X.
"Intense downpours could see up to 50mm of rainfall arrive in the space of just a few hours - almost the total average rainfall for August."
The yellow thunderstorm warning remains in place until 10pm on Wednesday.
Yellow flood warnings mean that there is a small chance that businesses and homes could experience flooding.
The Met Office also warns where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services.
Spray and sudden flooding could lead to difficult driving conditions and some road closures.
There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost.
This could lead to cancellations of public transport services and some road closures.
The hard ground after the sustained hot weather is expected to increase the risk of flash flooding.
The rainfall will be welcomed by many after London was declared to be under a drought after the record dry summer.
It has left London under a hose pipe ban and the capital's parks brown and dried out.