EM currency rally hinges on Turkey.

Turkey’s primary bank will offer an interest-rate judgment on Thursday, two days after a US-brokered respite in northern Syria is due to depart. More twists in the Brexit saga and slowing economic germination in China complicate the picture.

Emerging-market coins are winning fans again as the dollar wobbles, but their flexibility will be questioned during what’s becoming up to be a crucial week.

Turkey’s c....