[Kazun]

$sity = "kemerovo"
$source = "http://www.google.com/ig/api?weather="+$sity
$xml = [xml](New-Object Net.WebClient).DownloadString($source)
"current","forecast" | %{ $xml.GetElementsByTagName("$_`_conditions")| %{$_.icon.data}}

или

$xml.GetElementsByTagName("icon") | Foreach {$_.data}