The LHCb Collaboration has recently reported evidence for a $CP$ asymmetry approaching the percent level in the difference between $D^0\to {\pi }^{+}{\pi }^{-}$ and $D^0\to K^{+}{K}^{-}$. We analyze this effect as if it is due to a penguin amplitude with the weak phase of the standard model $c\to b\to u$ loop diagram, but with a $CP$-conserving enhancement as if due to the strong interactions. In such a case the magnitude and strong phase of this amplitude $P_b$ are correlated in order to fit the observed $CP$ asymmetry, and one may predict $CP$ asymmetries for a number of other singly-Cabibbo-suppressed decays of charmed mesons to a pair of pseudoscalar mesons. Nonzero $CP$ asymmetries are expected for $D^{+}\to K^{+}{\overline{K}}^0$ (the most promising channel for which a nonzero $CP$ asymmetry has not yet been reported), as well as $D^0\to {\pi }^0{\pi }^0$, $D_s^{+}\to {\pi }^{+}{K}^0$, and $D_s\to {\pi }^0{K}^{+}$. No $CP$ asymmetry is predicted for $D^{+}\to {\pi }^{+}{\pi }^0$ or $D^0\to K^0{\overline{K}}^0$ in this framework.

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