The hurricane that hit the stock market made landfall in the fall of 2018.

And now we are in what Rob Isbitts, the chief investment strategist for Sungarden Investment Research, considers to be the eye of the storm - the so-called calm before the next storm.

"I continue to think that late 2018 was a crash-test of sorts, and that we may very well be in that eye of the hurricane right now," he wrote in his latest column. "That means that at some point, the lows of 2018 will be taken out, and perhaps by a wide margin. But like a hurricane, it is unknown to all of us at what pace the financial markets moves from the eye phase to the resumption of the intense storm and the damage it inflicts on investors."

Given that, Isbitts said now is the time to be careful, to understand what you own, and respect the laws of gravity. "The best advice now is to be flexible, expect anything, and remember that preserving capital is always the priority at this stage of the market and economic cycle," he wrote.

According to Isbitts, his portfolios currently sit closer the middle of the risk spectrum than either the highly bullish or highly bearish end points. "This reflects a belief that defensive investing should be front-of-mind, but acknowledges the fact that markets are currently in a good enough mood to not be in a defensive shell," he wrote. "That can change very quickly, so as always, I encourage investors to assess their own portfolios for the impact of a sudden change in the environment, as we had just 6 months ago."

Related. Ask Bob: Home Sales, Capital Gains and Rental Property Taxes

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