Yes, it makes sense. We usually say "clothesline" instead of clothes horse though. And the sentence is very long. Perhaps you can make it into 2 sentences. I must say that I am impressed by your dedication to learning English.

The only issues are your lack of commas, the piece does mostly make syntactic sense. I would recommend this: There is a strong wind blowing outside. Therefore, you had better not leave the laundry on the clothes horse, as the wind is going to blow your laundry away. And besides, your clothes will not be dry by tomorrow morning, but leave them until then anyway. One other thing I would like to point out: without further context, the two sentences do contradict each other. First you say not to leave the clothes out due to the wind, then you say they should. But if this works in the larger context it's fine :)