The U.S. economic outlook is getting bleaker. 

As experts of financial markets and the economy debate whether there will be a recession next year or later, the chances of that one will come eventually are certain. A recession is defined as two consecutive quarters of negative GDP growth

"Certainly, there's growing risk of recession -- 2019, 2020, going forward," Chief Economist at LendingTree, Tendayi Kapfidze told TheStreet. Morgan Stanley economists wrote in a note Monday there is a 15% chance of recession in 2019 and a 30% chance in 2020. 

"I think by this time next year, we'll be looking in our rear view mirrors," said Danielle DiMartino, a former policy adviser to the Dallas Fed, referring to the fact that there may not be much expansion left in the economy. DiMartino is also the author of 'Fed Up: An Insiders Take on Why the Federal Reserve Is Bad For America.'  

The current streak of rising GDP is now almost ten years, almost equaling the longest U.S. expansion on record, which came between 1991 and 2001. Looking ahead, the economy seems due for some choppy waters. 

Economy Is Particularly Vulnerable

The economy's slow recovery from the Great Recession is making it particularly vulnerable to a recession. U.S. GDP grew by more than 4% in the second quarter of 2018, far less than the 7.26% growth it reached in 1984, according to World Bank data. GDP growth hovered around 1% and 2.8% between 2010 and 2017 as the economy recovered from the recession, which hit in 2009 and lasted for three quarters.

The current slow growth rate means that any external shock to the economy, like the housing bubble in 2008, could put it right into a recession. "If the economy is running at a slower pace, and you get an external shock, you're at more risk of dipping into negative growth," Kapfidze said.

The slow growth is not expected by many to pick up much in 2018.

"Our US economists expect US GDP growth will gradually decelerate from a peak of 4.2% in 2Q 2018 to 1.6% in 4Q 2019 and 1.5% in 4Q 2020," a team of Goldman Sachs strategists wrote in a note out Monday. Goldman said it's not predicting a recession, but weakening growth would make the economy even more vulnerable than it already is to an external shock, according to Kapfidze's logic. 

And some are concerned about excesses in financial markets, which has the potential to create that shock. "You worry about investment activity that's being funded by too much debt, and the risk that you have a build-up of imbalances," Barclays Chief Economist Michael Gapen told TheStreet a week ago.

He mentioned potential excesses in commercial real estate. Meanwhile, margin debt -- debt used by investors to buy stock -- is currently near its record level, sitting at around $650 billion, according to FINRA data. "Margin debt is very high," Ming Cen, managing director and senior researcher at Perella Weinberg Global Macro Fund told told TheStreet. Margin debt is currently 2.1% of the total stock market, far above its historical average dating back to 1970, according to NYSE data. Margin debt never hit as high as 2% of the total stock market between 1970 and 2006.  

Is the Fed Moving Too Fast?

If the Federal Reserve is raising rates too quickly, that could choke off growth in 2019. The Fed will likely hike rates in December, and has signaled a strong preference to do so several more times in 2019. Now, Federal Reserve officials are divided on the number of rate hikes the economy will need in 2019. There could be as few as two and as many as four. A hurting stock market is now making it even less likely the Fed raises rates four times in 2019. And DiMartino pointed out that falling oil prices is one factor that should give the Fed reason for pause. "This dramatic decline in oil prices" is something the Fed needs to watch more closely. The Brent Crude Oil Index is down 20% in the past month. House prices and prices of housing related goods are also falling. "We saw furniture sales get hit -- that's housing starting to bleed through into other areas of the economy," DiMartino added.

She also noted some investment grade bonds have sold off, signaling fears of worsening corporate credit. "Pay attention to credit market volatility," DiMartino said. The iShares iBoxx Investment Grade Corporate Bond ETF (LQD) is down 8.2% year-to-date. When bond prices fall, yields rise. 

"I don't see the United States exiting {2019 with strength}," she added. "A year from now I don't see us having a discussion about a continued expansion."

Investors worried about 2019 should pivot into a safer strategy. 

Investors Should Be Defensive 

"Lightening up on equity exposure if you're overweight equities" would be a solid move, Mike Loewengart, vice president of investment strategy at E*Trade told TheStreet. "Adding high quality fixed income has traditionally been a great way to cope with volatility, provide some balance in your portfolio," he added.

Dividends aside, buying utilities stocks could be defensive, the Goldman Sachs economists said. "We raise Utilities to overweight given the sector's track record of notable outperformance during decelerating GDP growth environments," Goldman said. Getting out of sectors that perform well in a booming economy would also be a smart move, Goldman said. "We recommend underweighting Consumer Discretionary, Industrials, Materials, and Real Estate." 

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