The OP question was a bit general- as different areas of Roatan suffer variously depending upon location.
With storms lashing the islands, the North side may be absolutely closed due to wave action-
but after it's all over, the North & West water clarity returns to normal
very quickly.
The South side is usually quite doable during most any storm. Boats go out and dives get made.
The downside is the localized siltation off of FIBR's beach that can pretty well occlude the Channel during storms. Southern boat dives return to normal quickly just as the North Side does. It's Roatan's most popular shore dive, off of FIBR & CCV that suffers the greatest impact.
CoCoView diving? Instead of shore diving the Channel, turn hard left and do the CCV Wall or Newmans. Once you get outside of the two buoys shown below, it's good viz.
No one likes the Ocean all clouded-up and with a layer of fresh water- certainly not the critters!
Weather log: http://www.docksidedivecenter.com/WeeklyLog.html
Remember that Roatan is simply not known for it's visibility. There are many times when a night dive is perfectly acceptable when if you tried it in the daylight, you would label it as murky. It all depends upon how far away you are looking.
The interesting stuff is in the size range that you have to be within 10' to spot it anyway, and then get in closer for a better look. So, inherently, viz is not as big an issue as it may first seem.
No matter where you dive after a storm~ North side, South shore, Roatan, Belize or Cayman- the critters are going to be shy with all of that churn and cold fresh water.