my %month = (
        Jan => 0,
        Feb => 1,
        ...
);

# ...

$month = $month{$month};  # Could stand to use better names

##</code><code>##

open(LOGFILE, "datafile.html") || die "Can't open file";

##</code><code>##

foreach my $log_line (<LOGFILE>)
{
     # ...
}

##</code><code>##

my $hour = param ("hour");
my $minute = param ("minute");