I read some about how targets might be chosen and looked at fallout maps. I wasn't able to find anything especially high quality. In a "destroy military targets" scenario Boston-area things are probably pretty far down the list; in a "destroy major cities" scenario less so. Nukemap can be useful for looking at how likely a bomb hitting various locations is to kill you in the initial blast, which affects trade-offs around getting out vs preparing to potentially shelter at home. My reading is that our house in particular is close enough to Boston that we would be unlikely to survive a bomb targeted there. If you are at an intermediate distance from a target, where are you are unlikely to be killed in the initial blast but likely to receive fallout, it's worth planning for the ~15min window between the blast and fallout arriving.
We talked as a house about how we might handle various scenarios. This was especially necessary since we share a car, though in most disasters we would probably stay put. This also included discussing what sort of escalation in Ukraine might make us leave Boston, but we really didn't get anywhere with that.
I had put together two emergency backpacks in Fall 2017 when I was thinking about disasters, and this seems like a good time to think about updating them. Some things were close to expiration (emergency food, medication) and our needs are somewhat different (8mo baby). Additionally, I hadn't done a great job choosing what to put in them the first time: I found this very stressful and needed to just put some things together and be done with it or else I wasn't going to finish at all. Julia volunteered to handle this, for which I'm very thankful. We also looked over our emergency supplies in general and got some things we decided we were missing.
We've started a lists for additional things we might bring if evacuating by car.
I bought water containers for my dad to keep it his basement (we already have some).
We moved some things around to make them more accessible in an emergency. For example, things that we might want to bring with us if either evacuating by car or sheltering in the basement (tent, portable crib, air mattresses) are now stored in a convenient place, when previously they were more scattered around the house.
A lot of these are not especially specific to the current situation, but instead more are taking the time to think through what might be useful in a range of disasters.