PROTO: *pinaʁ-
MEANING: to be good weather
RMEAN: вёдро, хорошая погода
NEWCOM: This stem is probably related to *pińi- 'good, beautiful' rather than to *pina-ʁ- 'to begin to melt, to break up (river), to overflow' or *pina-ʁ- 'to strive, convenient, diligent, useful'.