Every Thursday, Freddie Mac releases a report with the average mortgage rates. This is a weekly survey that's done Monday thru Wednesday each week, where they ask lenders what rate and fees they're charging for a 30-year fixed, 15-year fixed and 5-year ARM. The news picks up on this every Thursday and tells everyone "Rates are UP" or "Rates are DOWN."
There are two challenges with this survey. First, it's not real time. So data collected on Monday could be very different than what's available on Thursday in a volatile market. Second, people often ignore the average points (fees) being charged. People will see the average rate online or on the news, but they may not report the average points. It's very important to always know the rate and fees!
You can view the Freddie Mac Survey here: https://www.freddiemac.com/pmms