Hi, with the following code replacing your main code, 

my @tides = ( { time_in_seconds => 0,
                high_low        => 'Unknown',
                time            => 'Unknown',
               } );

foreach my $tides (@{$data->{data}->{item}}) {
   if($tides->{date} eq $today_date) {
     $tides->{highlow} =~ s/L/Low/;
     $tides->{highlow} =~ s/H/High/;

     my $format_date =  "$tides->{date} $tides->{time}";
     my $date_to_seconds = str2time($format_date);
     
     #print " Test: ".$tides->{highlow}, " Tide at: ", $tides->{time},
+ "\n";
     $tides->{time_in_seconds} = $date_to_seconds;
     push @tides, $tides;
   }
}
push @tides, { time_in_seconds => $now_in_seconds + 10000000,
               highlow         => 'Unknown',
               time            => 'Unknown',
             };

my @future_tides = grep { $_->{time_in_seconds} >= $now_in_seconds } @
+tides;
my @past_tides   = grep { $_->{time_in_seconds} <  $now_in_seconds } @
+tides;

my $next_tide     = $future_tides[0];
my $previous_tide = $past_tides[ -1];

print "Next tide: ", $next_tide->{highlow}, " Tide at: ", $next_tide->
+{time}, "\n";
print "iPrevious tide: ", $previous_tide->{highlow}, " Tide at: ", $pr
+evious_tide->{time}, "\n";
 
exit;

[download]
I get 

2013/03/27, 06:05 AM - Now in Seconds is: 1364378700
Next tide: Low Tide at: 06:20 AM
Previous tide: High Tide at: 12:21 AM

[download]
which might be close to what you wish. UPDATE Updated code to display something whatever the 'now' time is.

In reply to Re: Display tide based on time now. by Krambambuli
in thread Display tide based on time now. by Anonymous Monk

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