The Fed (FOMC) meets Mar 15-16, but I don't think the meetings are fixed length.
The Fed sets the loans for huge banks to borrow from the Fed directly, and those rates tend to make their way into treasury yields and even mortgage rates. Treasury yields have been very volatile recently, with stock investors panic driving down yields until the panic ends. That could happen again this week.
But if the stock & bond markets are calm leading up to the Fed announcement, I expect the rate hike to cause bond yields to drop very slightly! The huge majority expect a 0.25% rate hike (Fed Chair Powell has even said he will suggest 0.25%). But given the Fed acting too slowly and recent inflation, some think a 0.50% rate hike is possible. If you average those views, times the probability, you might have 0.26% average priced into the market. So if the Fed says 0.25%, the market only has to fall from 0.26% to 0.25% as the higher rate investors are shown to be wrong. If the market is finally calm (a big "if"), that's why I would expect a 0.25% rate hike to cause a small drop in yields.
If treasury yields suddenly jump 0.25%, that would represent a very inefficient bond market. I would probably invest even more in inverse bond yields to take advantage of it, rather than just waiting for the longer-term trend of rising bond yields.
