As for all metaphors, there is a choice, in principle, of two translations:
1. 'In the last few days, the wind of price falls (financial decline?), (like the squalls of winter?), after blowing for three weeks, has moved away from the Paris Bourse, but has returned (rather reluctantly?) and slightly brought prices down again.
2. 'After a three weeks decline in prices, the market stabilised, but recently there has been a slight downturn.'
Although the metaphor is prolonged and may be considered picturesque, I think it is rather daft, so I prefer the second version.