Macy's is heading into earnings in the middle of its best monthly winning streak ever. It hasn't seen a negative month since October.

Expect more gains after its quarterly earnings scheduled for release before the bell Wednesday, said Todd Gordon, founder of TradingAnalysis.com.

"It looks pretty strong," Gordon told CNBC's "Trading Nation" on Tuesday. "There's a level about $45.50 that was tested twice in 2016. I think that's going to act as an upside target."

Macy's bumped up against $45.50 in March 2016 and again in November of that year, but failed to hold the level. It spent 2017 trading below $40, but has rallied higher this summer. It pushed through $41.50, a level not seen since December 2016, on Tuesday.

If Macy's manages to rally up to $45, be wary of resistance above that 2016 peak, warned Gordon.

"I do like the trade but don't get too far out on this one because there's a lot of wood to chop up around $45," he said.

Larry McDonald, editor of Bear Traps Report, said a massive surge over the past 12 months could mean it is due for a pullback. Macy's has rocketed 106 percent higher over the past year, one of the best performers in the XRT retail ETF.

"You want to fade that," McDonald said Tuesday on "Trading Nation." "Mark my words, in the next 12 to 18 months you will have another stellar capitulation opportunity in the retailers and that's when you want to step in."

The XRT hit record highs Tuesday, besting the all-time highs set last week. Before Friday, the ETF had not hit records since March 2015.

Macy's is expected to post 4 percent earnings growth, but flat sales for its July-ended quarter when it reports Wednesday, according to analysts surveyed by FactSet.