LONDON (AP) — Britain’s record-breaking heat wave disrupted travel for a third day and firefighters remained on alert Wednesday even as cloudy skies and showers brought relief from the scorching temperatures of recent days.

Forecasters predict London will reach a high of 26 Celsius (79 Fahrenheit) on Wednesday, down from the record 40.3C (104.4F) set Tuesday at Coningsby in eastern England.

Still, the main train line from London to Edinburgh will remain closed until noon as crews work to repair power lines and signaling equipment damaged by a heat-related fire on Tuesday, according to the London North Eastern Railway.

The London Fire Brigade had its busiest day since World War II on Tuesday as firefighters received more than 2,600 calls and at one point were fighting 12 fires simultaneously, Mayor Sadiq Khan said. At least 41 properties were destroyed, he said.

Despite lower temperatures, the fire danger remains high because hot, dry weather has parched grassland around the city, Khan said.

“Once it catches fire it spreads incredibly fast, like wildfires like you see in movies or in fires in California or in parts of France…,” Khan told the BBC. “I’ve just spoken to the fire commissioner. He’s still concerned about the ground being dry and the speed of fire spreading.”

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