I think the mavic has two wind warnings. The first is a "Warning: Strong winds fly with caution" I get this in light-moderate winds and have mostly stopped worrying about it unless I know the winds are already starting to test the Mavic. The second one I've seen which I've only seen a few times is the "Strong winds, return home" line. This line I take more seriously since I don't see it as often so have less experience with it.
Winds can ramp up quickly as you clear the surrounding trees and buildings. Furthermore, the higher you get, the less winds are slowed down by objects and friction at ground level. Winds can quickly double or more in speed a few hundred feet up.
If I'm flying in strong winds, or am receiving unexpected warnings from my Mavic my first step is to see how quickly the Mavic will fly into the wind. If speed is greatly reduced and you're worried about getting it home, try reducing the altitude. Sport mode helps a lot in fighting high wind speeds, and I've flown mine in ~40km/h winds in sport mode (although it drained the battery fast and I wouldn't want to fly it far downwind). Worse case, try to get behind an object to shield it from the brunt of the wind and attempt a remote landing to wait for the winds to drop.