Forecasters have warned storms and heavy showers could bring flooding to parts of the UK.
The Met Office has issued a yellow warning for thunderstorms across northern England in areas including Middlesbrough, Carlisle, Scarborough and Lancaster.
The warning came into force at midday and will run until 8pm on Wednesday.
Find out the forecast for your area
Motorists and people travelling on public transport have been told to expect longer journey times – while buildings and homes could face damage from flooding.
The Met Office also warned of potential damage to buildings and structures from lightning strikes.
A separate yellow warning for rain which started on Tuesday is still in force for parts of Scotland.
Areas in Aberdeenshire could see flooding as heavy rain is slow to move away.
The warning for the poor conditions, which could also impact roads and transport, is in force until 4am on Thursday.
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The Met Office said conditions should warm up slightly and turn drier by the end of the week.
Central England is expected to see temperatures reach 22C (71.6F) on Wednesday – while the country’s coldest temperature of 3C (37.4F) is forecast in rural Scotland on Thursday evening.
