Stock futures edged up in overnight trading on Wednesday following a rebound on Wall Street as the market tried to avert the seasonally weak September.

Futures on the Dow Jones Industrial Average rose 30 points. S&P 500 futures and Nasdaq 100 futures both gained 0.1%.

Moderna rose slightly in extended trading after the company released more data on breakthrough Covid cases that supports the push for the wide use of vaccine booster shots.

The S&P 500 gained 0.9% Wednesday amid a 3.8% jump in the energy sector, posting its biggest daily increase since Aug. 27. The blue-chip Dow advanced more than 200 points, while the tech-heavy Nasdaq Composite rose 0.8%.

After seven straight months of gains for the S&P 500 and a near 20% rally to records this year, many on Wall Street expect bumpier trading and lower returns for the rest of the year. History is also not in the market’s favor as September tends to be a typically negative month for stocks. The S&P 500 has fallen 0.56% during the month on average since 1945, according to data from CFRA.

“The wall of worry is becoming increasingly challenging to climb, with rising depth and breadth of concerns and a potentially tired market,” said Mark Hackett, Nationwide’s chief of investment research.

So far this month, the 30-stock Dow is down 1.6%, while the S&P 500 has declined 0.9%, on track for its worst monthly performance since January. The Nasdaq has fallen 0.6% this month.

“The stress factors facing the market have not materially changed, including the Delta variant, earnings headwinds from supply chain and labor challenges, fiscal and monetary tailwind shifting to headwinds and bubbling concerns around China,” Hackett said.

Investors will monitor the latest jobless claims data on Thursday. Economists polled by Dow Jones expect a total of 320,000 Americans filed for unemployment insurance in the week ended Sept.11, slightly up from 310,000 in the week prior.

Traders are also bracing for a potential surge in volatility on Friday. The so-called quadruple witching will occur at the end of the week as stock and index futures and options are set to expire on the same day.