Cathie Wood and Jeremy Siegel both say that we're already in a recession while inflation shows signs of easing

• Ark Invest's Cathie Wood and Wharton professor Jeremy Siegel both think we're already in a recession.
• "I think we're actually in a mild recession," Siegel told CNBC, saying the economy likely contracted in the first half of the year.

Ark Invest CEO Cathie Wood and Wharton School of Business professor Jeremy Siegel both agree that we're already in the middle of a recession.

While recession warnings have been piling up in recent weeks, most of them have a timeline of one or two years in the future. But in separate appearances on CNBC Tuesday, Wood and Siegel said it is happening now, while inflation is showing signs of easing.

"We think we are in a recession, and we think a really big problem out there is inventories — the increase of which I've never seen this large in my career," Wood said.

She pointed to retail giants like Target and Walmart, which typically have well managed supply chains but have warned recently they are struggling with high inventories, indicating the size and scope of the problem is bigger throughout the sector.

To offload excess inventories, retailers will have to cut prices. And Wood reiterated her view that the current period of high inflation will set up the economy for deflation, or falling prices.

Wood noted that consumer sentiment has fallen to new record lows, dipping below levels seen during recessions in 2008 and 1981, as "the consumer is railing against" high inflation.

Recessions typically are defined as two consecutive quarters of GDP declines. The first quarter saw a 1.5% decrease, and data for the second quarter is due next month.

Siegel told CNBC the economy likely contracted in the first half of the year: "I think we're actually in a mild recession."

He added that indicators he is watching point to the economic slowdown continuing into the third quarter. In particular, he said data on US money supply has shown a decline, which also suggests "we are getting a handle on inflation."

But official inflation numbers haven't caught up yet, he added, as the the Bureau of Labor Statistics' monthly consumer price index report is too slow to account for housing prices.

"Jay Powell and the Fed have to recognize that we're going to get some bad prints that are gonna continue on that actually represent past inflation that has to move through the system," Siegel said.