well that was an adventure
there's no weather plasmoid in the kde that comes in the porteus download, and the only one i saw listed in the packages was wmweather for windowmaker, but i expanded my search and just looked for plasma/plasmoids etc and found kde-plasma-addons
so i installed it, and its truckload of dependencies, it pulled in nepomuk and akonadi and i dont remember what else all, all the pim stuff.
and my kde menus disappeared completely, everything except the bottom section favorites>, run command, and leave>
so i thought hm, i'll go disable nepomuk like i did kscreen, just a stab in the dark
no joy there, so since i had made a subfolder with the packages, i went then and uninstalled them, and porteus broke, it wouldn't boot to GUI at all anymore.
so i thought, maybe something i have set my way is breaking this. so, i deleted my changes folder, and installed on a fresh virgin porteus, the usual things i install to start, without really making any configuration changes except whatever the packages themselves install. gstreamer and its plugins, wine and wine gecko and mono, and booted with that once, to see that it did it, and it did. installed the plasma addons folder of packages, and it broke porteus again exactly the same way. killed the menu, and uninstalling the folder broke porteus the rest of the way.
i haven't gone over it with a real deep attention but i'm sure at least part of what is going on, in the uninstalling, is that one or more of those packages are different versions of something thats in core porteus already, and thats why uninstalling breaks things. and maybe have some to do with the menu getting killed too, in the installing.
there are two weather plasmoids in it, and they work, if i can figure out how to get at them without blowing up the world