Mortgage rate may not be quite as low as they were on January 31st, but they nonetheless managed to end at the lowest levels of this week. Unlike January 31st, we can still say we're at the lowest levels in more than a year (yesterday was the first official day for that distinction).
All of this is beside the point. We're effectively as low as we've been in a long time. The average lender is once again able to quote conventional 30yr fixed rates below 4.5% for the best-qualified borrowers.
Beyond that, there's at least an equal chance that rates could go lower in the short-to-medium term depending on economic data and the resolution (or lack thereof) of several lingering uncertainties. Those uncertainties include but are not limited to the status of the government shutdown, the March 1st US/China tariff deadline, the Brexit process in Europe, and the ability (or lack thereof) of the stock market to get back to 2018's highs.