my $re = qr/
( \d+ ) # $1 id
\s+
\d{4}-\d{2}-\d{2}\s ( \d{2} ) :\d{2}:\d{2} # $2 hour
\s+
(\S+) # $3 val
/x;

while(<>){
  if( /$re/ ){
     my( $id, $hour, $value ) = ( $1 , $2, $3 );
     ...