If you're watching for signs of a looming recession, pay attention to commodity prices.

Copper (HG=F) futures are down about 8% in the last six months despite a recent rebound. The price of the metal, used for everything from wiring to construction, is 17% lower from March 2022 levels.

"Copper is this profoundly important raw material for all of these electrical vehicles and how we're going to transform energy and remove carbon," Hugh Hendry, investor and former global fund manager told Yahoo Finance.

"The price is falling and falling. It's very weak. These are very large, very global, very liquid markets. And, and they're suggesting caution," he added.

China's lackluster recovery following its strict Covid lockdowns in 2022 has put pressure on crude, despite the world's largest exporters announcing output cuts in hopes of keeping a floor on prices.

The recent banking turmoil in March intensified a market sell-off in commodities amid fears of a recession due to a credit reduction.

Hendry says the bank failures of Silicon Valley Bank and Credit Suisse point to an ominous sign for the economy.

"You typically get bankruptcies when credit costs escalate and it reveals the folly that is yet to happen," he said.

"A recession is brewing onshore in the US. It's certainly there in Europe, it's there in in Germany," added Hendry.

Some sectors of the economy, like commercial real estate are contracting. Others, like travel and leisure, are still going strong.

Some strategists are waiting for more signs to determine when the US will enter a recession. Many Wall Street economists have dialed back expectations that one will occur this year.

"We do not believe that we will enter a recession in the US in the short run as the US housing sector is resilient due to a shortage of homes for sale. Every prior recession has been precipitated by a major decline in the housing sector," Jay Hatfield, CEO at Infrastructure Capital Management told Yahoo Finance.