At 0630 GMT, the rand traded at 15.0700 against the U.S. dollar, 0.25% firmer than its previous close.
With a light local data calendar this week, the rand's movements have been mainly driven by offshore events.
The currency rallied to a 2021 peak of 14.3950 last week on fiscal consolidation plans laid out by South Africa's finance minister, but has struggled to firm further as soaring U.S. bond yields sapped enthusiasm for risk currencies worldwide.
A renewed sense of calm in the Treasury market has underpinned sentiment in recent days but Bianca Botes, executive director at Citadel Global, said in a note that "slowly rising yields are continuing to see some caution in markets."
Investors waited to see if Powell, who is due to speak at a Wall Street Journal conference at 1705 GMT, would address concerns about the risk of a rapid rise in long-term borrowing costs.[MKTS/GLOB]
Government bonds weakened in early deals, with the yield on the instrument due in 2030 rising 11 basis points to 9.145%.
(Reporting by Olivia Kumwenda-Mtambo; Editing by Aditya Soni)