Drew Angerer/Getty ImagesSummer is traditionally regarded as a sluggish time for U.S. stocks, given the Wall Street adage: “Sell in May and go away.” This year, though, may turn out to be markedly different from past years.One reason is bullish investors are steadfastly holding on to the view that U.S. inflation is set to fall by more than the Federal Reserve forecasts, and that’s setting the stage for a possible showdown in the months ahead with policy makers, who want more interest-rate increases to push inflation back down to 2%. The S&P 500 SPX and Nasdaq Composite COMP booked their longest streak of weekly advances in years on Friday,as equity investors largely brushed aside the Fed’s guidance that it will likely be appropriate to lift its policy interest rate to around 5.6% by year-end from a current level between 5%-5.25%. Ultimately, it will be up to economic data to determine whether the market has gotten ahead of itself by thinking that the Fed won’t have the nerve to deliver two more 2023 rate hikes.Read: Why the stock market shook off a ‘Jekyll and Hyde’ Fed meetingChris Zaccarelli, chief investment officer for Independent Advisor Alliance in Charlotte, N.C., which manages $10 billion in assets, said his firm believes that “inflation is here to stay and risks becoming entrenched unless the Fed raises rates much more than the market is currently expecting.”Theoretically, Zaccarelli said by phone, policy makers would need to raise rates by another 75 to 100 basis points — or more than the 50 basis points of hikes implied by policy makers’ projections — to put inflation on a path toward 2%. However, he doesn’t see that happening. Fed officials are “talking tough, but we don’t think they will actually hike more than one more time, before holding rates steady above 5.25%-5.5% for six to 12 months.”On Wednesday, Fed Chairman Jerome Powell is set to begin the first of his two-day, semiannual testimony to Congress — which should provide investors further insights into his thinking.Since inflation began rising in 2021 after the onset of the pandemic, investors have repeatedly underestimated the Fed’s willingness to tighten financial conditions or, at the very least, taken a while to get on board with the central bank’s thinking. That’s the case this time around, as well, with fed funds futures traders pricing in only a small chance of a quarter-of-a-percentage-point rate hike by the Fed in September, following a similar move in July. However, the Treasury market seemed to finally be absorbing the Fed’s hawkish message on Friday, two days after it was delivered.Markets are caught in a somewhat complicated moment, in which there’s plenty of disagreement over what lies ahead.Inflation has fallen from a 9.1% peak reached last June, as measured by the annual headline rate of the consumer price index, and is showing signs of further easing. Stocks are being buoyed by enthusiasm over the prospects for artificial intelligence and by big-name tech companies, like Nvidia Corp. NVDA and Apple Inc.AAPL. Finally, a much-talked about U.S. recession hasn’t actually arrived, with labor-market strength keeping the unemployment rate at 3.7% as of May.Yield-seeking investors helped keep Treasury rates mostly contained between March and May, but the prospect of more Fed rate hikes by year-end has pushed the 2-year yield BX:TMUBMUSD02Y to three-month highs in June. Meanwhile, the bond market is still pointing toward the likelihood of a U.S. economic downturn, as demonstrated by more than 40 different inverted Treasury yield spreads as of Friday.The continued gap in expectations boils down to a fundamental difference between what markets appear to be wanting the Fed to do — which is put a quick end to its most aggressive rate-hike cycle in four decades — and what the Fed is duty-bound to do — keep hiking until inflation falls swiftly back to 2%. Data released last week showed one core gauge of the May consumer price index, which strip out food and energy to provide a purer read on inflation, at 5.3% for the past 12 months versus 5.5% previously —- much too high for the Fed’s liking. Stock investors have instead focused on the annual headline CPI rate, which dropped to 4% last month: The S&P 500 and Nasdaq Composite respectively ended Friday with their longest weekly streak of advances since the five- and 10-week periods that ended on Nov. 5, 2021, and March 1, 2019.“We are at a stalemate between what the Fed wants to accomplish and what the economy will continue to do,” said Zaccarelli of Independent Advisor Alliance. He describes the U.S. as being in “a no man’s land in which the economy muddles through, inflation stays above 2%, and the Fed doesn’t want to do more damage than it already has.”“Not only is the unemployment rate too low in order to win the fight against inflation, but the wealth effect from booming stock markets is going to exacerbate the problem,” Zaccarelli said. Stocks trading near record highs are going to reduce the incentive for consumers to cut back on spending, and “only a recession or another bear market in stocks has the ability to shock consumers into cutting back.”Read: Big stock market rally to be followed by ‘big collapse,’ says BofA’s Hartnett and Stock market could face $150 billion headwind from rebalancing sales: JPMThe summer months are often referred to as the “summer doldrums” because of the tendency of equities to underperform. Historically speaking, June, July and August tend to produce lower returns in the S&P 500 SPX than other parts of the year, according to Dow Jones Market Data. The average performances for each month is -0.3% for June, +1.4% for July, and -0.61% for August — versus +1.92% in November, +1.73% for April, and +1.62% in October, based on data between January 1990 and May of this year.Stocks could be particularly vulnerable to a pullback over the summer if incoming data swings expectations back toward the Fed’s projections. It’s not just stock-market bulls who may turn out to be wrong about the central bank’s ability to hike twice more this year. Bearish portfolio managers have been “hedging their positions because they don’t want to miss out on the AI frenzy,” which has helped to juice the recent rally in stocks, said Eric Sterner, chief investment officer at Apollon Wealth Management, which manages $3.9 billion from Mount Pleasant, S.C. “The market is overvalued right now and it’s a house of cards because it’s being driven by mega-tech stocks,” Sterner said via phone. “We are remaining defensive by focusing on maintaining or looking at companies or funds that are less sensitive to the S&P 500’s direction because we still think we will hit a recession, potentially in the fourth quarter or early 2024.”

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