As KE said, lightweight and outdoors are not synonymous! Sand bags and an assistant are usually best! A little scouting to check location and prevailing wind conditions is also a good idea. Sometimes a small shift in the location can minimize the wind.
That said... Phottix makes some carbon fiber light stands that could help with weight but they are not cheap. The other solution is a boom arm which allows the addition of a weight to the end of the arm (plus sandbags). The arm can also help to get better angles for subject light. I also use an extension head which allows the mono light body to located near the feet to lower the overall weight. The real issue can be the modifier which if there is wind can be a problem. In that case, sandbags, extension head and or an assistant will be helpful to at least contain the problem.
I’ll add from experience that cheap light stands tend to be more problematic. I get that C stands work best but they are heavy. Get a reasonably robust light stand with a boom arm and go from there. I use Phottix stands but there are others. I believe Flashpoint from Adorama has some reasonably priced stands that are fairly robust and you might want to check that out.
hope that helps
Tim