The Labor Department's August Consumer Price Index landed right on the line Wall Street feared Friday morning, keeping pressure on the Federal Reserve to raise interest rates at its meeting next week rather than hold steady. Headline CPI rose 0.4% for the month and 3.4% from a year earlier, matching economists' forecasts, but core inflation — which strips out food and energy — climbed 0.3% on the month, a tenth of a point hotter than expected, holding the annual core rate at 2.4%.

The report is the last major inflation reading the Fed will see before its policy meeting on September 16, and traders reacted almost immediately. According to CME Group's FedWatch tool, the implied probability of a quarter-point rate hike jumped to roughly 90%, up from about 70% just a day earlier.

Gas and Diesel Do the Damage

Much of the upside surprise traced back to energy. Gasoline prices rose 3.9% in August alone and are up 27.4% over the past year, according to the Bureau of Labor Statistics data reported by Fox Business. Diesel hit a record $6.06 a gallon nationally on Friday, more than 60% higher than a year ago, while the national average for regular gasoline reached $4.30 a gallon. Economists noted gasoline alone accounted for more than a third of the month's overall CPI increase.

"Today's CPI came in broadly as expected, which on the surface is the outcome investors were hoping for, but it does make next week's rate decision a jump ball," said Alexandra Wilson-Elizondo of Goldman Sachs Asset Management, a comment carried by both Fox Business and CBS News.

"America has an inflation problem and it's more than just high gas and diesel prices... The Federal Reserve needs to hike in September to prevent this from worsening," said Heather Long, chief economist at Navy Federal Credit Union.

Adam Crisafulli, head of the research firm Vital Knowledge, was blunter still, telling CBS News that the inflation data "is still hot" and represents "more than enough to justify" a hike this month.

Equity markets initially took the in-line headline number as a relief rally, with the S&P 500, Dow and Nasdaq each gaining roughly 1% in Friday trading. But the reaction in rates markets told a different story: short-term Treasury yields pushed higher as bond traders repriced for tighter policy, a sign investors see the Fed's inflation fight as unfinished business even as stocks cheered the headline match.

The report caps a volatile stretch for Fed-watchers. Governor Christopher Waller had signaled in recent weeks he could support holding rates steady if disinflation continued, but Friday's hotter core reading undercuts that case just days before the central bank's rate-setting committee meets. With energy costs still climbing and the labor market holding up better than expected, the Fed now faces a decision that markets increasingly expect to end in a hike — the central bank's first in more than three years, after a rate path in 2026 that has otherwise held steady between 3.5% and 3.75%.

For consumers already contending with mortgage rates above 7% and real wages that ticked down 0.1% between July and August, the outcome next Wednesday will help determine whether borrowing costs climb further just as pump prices show no sign of relief.