You may not wash or hang up wet laundry on Jewish festivals (or Shabbat).  The halachot for drying laundry depend on whether you use a clothesline or a dryer:
Jewish Festivals: Laundry: Clothesline
You may only take down laundry on Jewish festivals if it was dry before sunset at the start of the festival, and only if you don't:

• Transfer the laundry from one halachic domain to another (hotza'a), or
• Give the impression that the laundry had been washed on the Jewish festival (mar'it ayin).

If laundry on a clothesline is still wet at sunset before the festival, the laundry is muktza and you may not take it down or use it during the festival. This is different from the case of a dryer.
Reason On the clothes line, there is no certainty that the laundry will dry during the festival (it might rain, it might be cold or cloudy...), so the person may not have in mind that it will dry during the festival.
Jewish Festivals: Laundry: Dryer
Laundry in a dryer (even if it was wet at sunset) that was turned on before sunset beginning the Jewish festival (or Shabbat) is not muktza, even if you do not intend to wear it.  You may remove the dry laundry from the dryer on the Jewish festival as long as no light goes on.