Investors are keeping a close eye on Federal Reserve Chair Jerome Powell’s speech at Jackson Hole on Friday morning, but investors deal with the event as a buying opportunity no matter what Powell says, according to Fundstrat.

The company’s head of research, Tom Lee, called Powell's speech "a buyable event" in a Thursday note, adding a market rally even if Powell makes hawkish comments.

"We think there is growing probabilities inflation weakens faster than consensus expects," Lee said, adding there are signs that the implied Fed funds rate was actually 90 bp tighter than it needs to be.

The 12-month forward, a measure of inflation expectations a year from now – currently sits at 2.7%, although the implied policy rate by year-end is 3.6%, according to data from Bloomberg.

Despite July's 8.5% Consumer Price Index reading, Lee noted that CPI often lags behind actual inflation in the economy, with changes taking up to a year to show up in reports. 

And besides the falling CPI, there are other signs inflation is starting to cool. Regional Purchasing Managers' Indices, which measure the prices that manufacturers are paying, have calmed down, according to data from multiple Fed banks. According to the Federal Reserve Bank of New York, oil and commodities prices are also falling, in line with consumer inflation expectations.

That could mean the Fed isn't as behind on the inflation curve as some investors are anticipating – good news for investors hoping for another market rally by year-end, Lee said, who previously predicted the S&P 500 would reach all-time highs before 2023.