#! perl -slw
use strict;

local $/ = ''; ## paragraph mode

while (<DATA>)
{
        my $k = '\d{1,3}[SNEW]{1,2}';

        while ( /\G.*?(($k ){3}$k)/msg )
        {
                print "*$1*";
        }
}

__DATA__
MAX SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT.
64 KT....... 25NE 0SE 0SW 25NW.
REPEAT...CENTER LOCATED NEAR 17.0N 77.5W AT 11/2100Z

MAX SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT.
64 KT....... 25NE 0S 0SW 25NW.
50 KT....... 40NE 0SE 0SW 40W.
34 KT.......100NE 75SE 0SW 75NW.
12 FT SEAS..175NE 100SE 50SW 175NW.
REPEAT...CENTER LOCATED NEAR 17.0N 77.5W AT 11/2100Z
__END__
[download]

OUTPUT:
*25NE 0SE 0SW 25NW*
*25NE 0S 0SW 25NW*
*40NE 0SE 0SW 40W*
*100NE 75SE 0SW 75NW*
*175NE 100SE 50SW 175NW*