This code will find the latest tide info before current time. Disclaimer: I cannot test the code as some missing modules resist installation on my box now.

my $last_time = 0;
my $current_tide = "We have a problem!";
foreach my $tides (@{$data->{data}->{item}}) {
    my $format_date =  "$tides->{date} $tides->{time}";
    my $date_to_seconds = str2time($format_date);
    
    if( $date_to_seconds > $last_time and $date_to_seconds < $now_in_s
+econds ) {
    $tides->{highlow} =~ s/L/Low/;
    $tides->{highlow} =~ s/H/High/;
    $current_tide = " Test: ".$tides->{highlow}." Tide at: ".$tides->{
+time};
    $last_time = $date_to_seconds;
    }
}
print "$current_tide\n";
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