Of course, lower interest rates could hamper further upside for FXA. Fortunately for Aussie bulls, there are other factors to consider. [Aussie Dollar ETFs Could See Near-Term Upside]

For example, ANZ Bank no longer expects RBA to lower rates by next February. In fact, ANZ is now forecasting the first rate hike to occur in 2015 with an eye toward Australian rates of 4% by the first half of 2016.

“Market data indicate there is only an 11% chance RBA lowers rates at its November meeting and most traders now believe that if another rate cut is coming, it will happen in February 2014,” according to Investing.com.

Additionally, swaps data indicate traders only see a 22% chance RBA cuts rates by the end of 2013, down from 37% last month. That could be a harbinger of more upside for FXA.

CurrencyShares Australian Dollar Trust