If there's a blank line between the records as you showed, you can use "paragraph mode" (local $/ = "";).

local $/ = "";
while (<>) {
   my ($station, %fields) = /(\S+)/g;
   print(join(' ', $station, @fields{qw( N E U )}), "\n");
}
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Or if the values can contain whitepace,

local $/ = "";
while (<>) {
   my $station = s/^(\S+)\s+// ? $1 : undef;
   my %fields = /(\S+)\s+([^\n]*)\n/g;
   print(join(' ', $station, @fields{qw( N E U )}), "\n");
}
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