Using the Feb 2018 "Beast from the East" SSW to illustrate the point that the zonal winds at 60°N do not generally reverse to easterlies much below 20-30 hPa.

In the zonal-mean, it's the *anomalous* weakening which propagates downward (i.e., the negative Northern Annular Mode).

Here's what the 0 wind line does at 60°N across all SSWs in JRA55 courtesy of @zd1awrence https://twitter.com/zd1awrence/status/1344324552910925825?s=20

So, if you're looking at a forecast like this and feeling unhappy that the 0 wind line doesn't get below 30 hPa - fear not, that's pretty normal for a major SSW, and doesn't preclude a tropospheric impact as the lower-stratospheric winds are, and will remain, weak.