And, this didn't peak your interest at all?-- because it's pretty badass and really what you should have wanted to learn!
It makes useful use of your users' computer power and saves your server from doing extra stuff it really doesn't need. It also reduces the overall size of the transfer! Stop polluting the internet, thanks! ;]
<style>
.storm { background-color: black; color: #FFF; border: 1px #666 solid; text-align: center; font-size: .9em; }
.storm.weak { color: rgb(255, 255, 0); }
.storm.strong { color: rgb(255, 0, 0); }
</style>
<?php
echo '<td class="storm ' . $tintensity . '">' . $tintensity . '<td>';