Great question.
We've now taken our drysuits on two tropical dive trips (
http://www.scubaboard.com/forums/bay-islands/370556-roatan-trip-report-photos-videos.html and Utila) and overall we've been happy with those decisions. My wife and I are both relatively thin and easily get cold. If you're doing several dives each day, for multiple days in a row, even waters in the low-80s F will start to have an effect. I know on this last trip, many divers (include the DMs) were shivering by the last dive, especially topside when the boat was underway. If your primary concern is in-water comfort, a drysuit can really help (Jen no longer even owns any wetsuits). We both hate being cold.
That said, there are a few issues to consider when diving dry in tropical waters. First, you really want a lighter drysuit, mostly for travel weight/space reasons. I usually dive my compressed neoprene wetsuit here in Southern California, but it's just too big for easy travel. Fusions, TLS/FLEX, E.Lites, etc would all make great travel suits. Second, you want to bring a very light, but good wicking undergarment to wear under the drysuit. We mostly settled on 100-150g weight (equivalent) Capilene (or similar). That's plenty to keep you warm in the water and comfortable topside. Third, you want to minimize over-heating topside. I think topside conditions in both Roatan and Utila were in the low-80s F. That isn't too much warmer than what we typically see here in SoCal (and we're wearing MUCH thicker undergarments), so the same general "rules" apply. Stay in the shade when possible, only have the suit pulled up to your waist, don't put on or zip up the undergarment top until near the dive site, hydrate, etc. Fourth, given most small boats don't have a head, it really helps to have a pee-valve on the suits. There are options for both men and woment now. Fifth, the biggest hassle (for us) was simply that it takes a bit longer to put on the drysuits than a wetsuit. We typically would start getting dressed before getting on the boat; getting to the point where the drysuits were only pulled up to our waists (putting the undergarment tops in a dry bag for the ride out to the dive sites). As we approached the dive site, we'd go ahead and put the tops on, and finish securing the suits. Never over-heated. During surface intervals, we'd either pull the suits down to our waists again, or usually, just leave them zipped up. When they're wet, you don't get too hot in an hour.
If you already have the suit, feel comfortable diving it, plan to travel with your own gear anyway, and can easily and cheaply acquire some light undergarments, I see no reason not to give it a shot. In any case, hope you have a great trip!
Hi Christopher!
Great video and write up about Utila.
Diving dry down in the tropics must have some challenges that aren't associated with dry suit diving in colder climates. I'm heading down to Roatan in the next month, and would prefer to dive dry opposed to wet for most of my dives.
What recommendations do you have for dry suit diving in both warmer water and climates experienced in these environments?
BRad