No, but you can get it using COM.

alias envar {
if ($com(a)) { .comclose a }
.comopen a WScript.Shell
if ($comerr) { return }
var %a = $com(a,ExpandEnvironmentStrings,3,bstr,$+(%,$1%))
%a = $com(a).result
.comclose a
return %a
}

//echo -a $envar(systemroot)