Here are five key things investors need to know to start the trading day:

1. Fed head

Stock futures were higher Wednesday ahead of the Federal Reserve's rate decision. S&P 500 futures gained 0.2%, Nasdaq 100 futures advanced 0.3% and futures tied to the Dow Jones Industrial Average ticked 0.1% higher. The Fed is likely to keep rates unchanged but could move markets with its economic outlook. Among the things to watch for is Fed Chair commentary on inflation and political pressure from President . Follow live market updates.

2. Giving way

Homebuilder sentiment is falling through the floor. The June read from the National Association of Home Builders (NAHB)/Wells Fargo Housing Market Index (HMI) dropped 2 points from the prior month to 32. Anything under 50 is negative sentiment. All three of the index's components — current sales conditions, sales expectations in the next six months and buyer traffic — fell month over month. "Buyers are increasingly moving to the sidelines due to elevated mortgage rates and tariff and economic uncertainty," said NAHB Chairman Buddy Hughes.  

3. On the brink

Trump is weighing whether to launch a military strike against Iran, current and former administration officials told NBC News, which would step the U.S. more firmly into the country's conflict with Israel. The option is one of several under consideration after Trump met with top national security advisors in the Situation Room on Tuesday, the officials said. Trump has demanded that Iran's leader Ayatollah Ali Khamenei "surrender," saying in a post on Truth Social, "Our patience is wearing thin."

4. Replaced by AI

AI is coming for Amazon jobs. CEO Andy Jassy told his employees this week that the company's workforce will shrink in the coming years as generative AI becomes more prolific. "We will need fewer people doing some of the jobs that are being done today, and more people doing other types of jobs," Jassy said in an employee memo. "It's hard to know exactly where this nets out over time, but in the next few years, we expect that this will reduce our total corporate workforce." Amazon has laid off more than 27,000 workers since 2022, including several rounds of cuts this year.

5. Chasing perks

JPMorgan Chase is giving its premium credit card a refresh. The Chase Sapphire Reserve will get new perks, including a new points redemption program for travel and a $500 annual credit toward select hotels and resorts. The card is also getting a new annual fee of $795. The update comes as JPMorgan Chase and American Express ratchet up their offerings in the ever-expanding premium card rivalry — but they risk turning some customers away with the steep fees. "These premium cards are going more luxury, and I wonder if the $800 fees are becoming too much for some to stomach," said senior Bankrate analyst Ted Rossman.

– CNBC's Lisa Kailai Han, Jeff Cox, Diana Olick, Kevin Breuninger, Annie Palmer and Hugh Son contributed to this report.