If there's a delay and we're sitting on the ground where we're allowed to use cell phones, I'll call, explain that there seems to be a WX or MX on my flight, and ask to be protected on a later flight, both to substitute for the one where I'm currently waiting, and also for any downstream connections that I might miss. In fact, on a recent flight I wasn't thinking and temporarily forgot to do this but then noticed a guy near me trying to make the call. I hit my elite line and was rebooked while he was on hold waiting for a phone agent to answer. Priceless!