UK Met Office forecast charts from which all other websites are taken.  Usually available up to one hour earlier than the mirror sites

If two charts are apparently for the same date/time, use the one based on more recent information, eg if a Wednesday appears in both H+84 and H+96, use the H+84 as it is a more recent forecast. 
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H+0 (Analysis)H+24H+36H+48H+60
H+72H+84H+96H+120