The Financial Times analysis of all polling on the Euro elections says that the Tory vote will collapse to Farage (half of those who voted Tory in 2017 will vote for Farage and one in eight will support a remain party) leaving the Tories with 14%. The worst previous performance for a governing party was 15% for Labour under Brown.
Labour will lose 28% of its 2017 vote to remain parties and 13% to UKI or the Brexit Party. Their likely total vote is 25%. Farage is to come top with 29%. Remain parties will get 29% between them.
I have voted Green (postal vote).