Source: yweather.phps - download
<select name="" onchange="window.location='?city='+this.value;">
<option value="SAXX0017">Riyadh</option>
<option value="SAXX0013">Makkah</option>
<option value="SAXX0012">Jeddah</option>
<option value="SAXX0002">Dammam</option>
</select>
<?php
$city = (strlen($_GET['city'])==8)?$_GET['city']:'SAXX0017';
$data = implode('',file('http://xml.weather.yahoo.com/forecastrss?p='.$city.'&u=c'));
preg_match_all('/<yweather:([a-z]+)\s(.+)\/>/',$data,$tags);
foreach ($tags[0] as $k=>$var){
preg_match_all('/([a-z]+)="([a-z0-9]+)"/i',$tags[2][$k],$atts);
foreach($atts[0] as $k2 =>$var2){
$att[$atts[1][$k2]] = $atts[2][$k2];
}
if($tags[1][$k] == 'forecast') $tags[1][$k] = $att['day'];
$yw[$tags[1][$k]] = $att;//Yahoo Weather
}
print_r($yw);// usage $yw[Tag][att];
?>