Rain alerts have been stepped up for the weekend in parts of Great Britain, with the Met Office issuing flood warnings in the north-east on Friday and Saturday.

Public and civic authorities have been asked to brace for the wettest patch this season as more than 60mm of downpour is expected to cause disruption in areas coming under the amber alert.

The weather forecast is so severe on Friday that the Met Office said Friday’s rain can match the average rainfall for July, which is 69.9mm countrywide and 64.4mm in the north.

A Met spokesman said the pelting could be “prolonged, quite persistent and heavy”, cautioning that it could cause “surface water flooding” and “river flooding”.

“The public should be prepared for disruption to travel and outdoor activities. The rain across central England, East Anglia and south-east England should ease later in the day”, the spokesman said.

MeteoGroup’s Nick Prebble also warned the public against heavy rains on Friday, saying that there could be “20mm (0.8in) fall in six hours in some places on Friday morning. It will be very heavy and there will certainly be a risk of flooding”.

Amid widespread rain alerts issued for the weekend, the Met Office also has bad news for Thursday when the south-west could be in for severe storms and torrential downpours.

The month of April recorded the highest amounts of rain since 1910, while last month witnessed almost twice as much rainfall for the average June volume, surpassing the previous high of 136.2mm in 2007.

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