The UK Ministry of Defence (MoD) said 1,295 migrants make the journey on August 22 topping this year's highest total of 696, recorded earlier this month, Report informs referring to the Express.co.uk.
The spike follows a weekend of poor conditions meaning people were unable to make the dangerous trip.
A government source said there was a "backlog for smugglers to clear" as conditions improved on August 22 but the weather still wasn't seen as "ideal".
The MoD said a total of 27 boats were detected.
At least six RNLI lifeboats were called out as far as Eastbourne to rescue migrants after three Border Force catamarans become overwhelmed.
Most of the arrivals were from Albania, according to Border Force.