Captains Dave and Nan Fuller offer good advice and recommendations of routes and stops on the sail from Marco Island to Marathon, as originally posted on the AGLCA Forum, www.greatloop.org.

We made this leg of our Loop in August 2013, and it was the roughest open water we have yet encountered, probably because we were on a deadline to get > to the Keys. Our Carrabelle to Tarpon Springs leg was glassy smooth as we were patient and waited nearly 3 weeks for a suitable weather window. I mostly used NOAA and Weather Underground for my weather forecasts from Ft. Myers to the Keys but did not make a go-no go decision based on weather as it was predicted to remain the same for several days and it was within my personal tolerance of seas 2-3 feet. We had wind from the northeast and east during the three day trip from Ft. Myers to Islamorada. Day one, we traveled from Ft. Myers to Marco where we met a close friend and his wife for dinner and then the next day we left Marco for the Little Shark River anchorage in the Everglades. Everyone told us to beware of bugs, but there was
sufficient wind blowing day and night so they were almost zero problem in August. I was even able to grill out after dusk and only had a few horseflies to deal with. We highly recommend Little Shark River as an anchorage as it is well protected in every direction except southwest and if you go a little deeper up river, it offers protection in every wind direction. The trade-off will be the amount of bugs to deal with. After spending one night at anchor, we continued around the Cape and to the Keys. We have friends in Islamorada, so we did not go to Marathon by boat. We spent a few days in Islamorada and rented a car to go to Key West and be tourists.
If I take this route again, I will stay further offshore going around the Cape. We basically followed the boundaries of Everglades National Park and went over so much shallow water that I finally shut off my depth alarm. We never hit bottom, but this is an area where shallow water is the rule and the charted depth pretty much matched what we experienced. Interestingly, the closer we came to shore, the bumpier it became and the further off shore, the smoother. This was with a 25 MPH east wind. We had constant 2 foot seas with occasional 3 and 4 footers. I think that the bottom profile is such that because of a slow slope, it gives the wave energy extra lift making for steeper waves and the deeper water makes them more of a roller profile. Normally, when you are behind a reef, you experience smoother water than on the windward side, but that was not the case here. Waves were on
our port forward quarter resulting in nearly constant spraying and were more bothersome than uncomfortable. However, our dinghy came loose and was thrashing about on the davits and we just had to let it swing as it was not safe to go on our swim platform to secure it. It did some damage to the
davit mounts and bracing that required repairs, but the dinghy sustained zero damage.
I am not an expert on weather in this area, but my understanding is that typically the winds are out of the northeast (bad weather) or east (prevailing) or even southeast (best possible for this leg). I understand it is rare to have winds out of the west quadrants unless associated with a storm. We spoke to one skipper in Marco who had come from Key West the previous day and said they got beat up by 6 footers in the same wind conditions, but they took a much deeper water track than hugging the coast as we did. There is only one area you will need to watch with a well-marked channel marking the opening between two reefs. You make an S turn and it is very easy – no problems. As you approach the Keys, crab pots are EVERYWHERE and can only be described as a mine field, even in the middle of the marked channel. Keep a sharp lookout, go slow, and forget your depth alarm – it will be useless.
If you follow Tom’s weather musings for the Big Bend crossing, he posts a disclaimer that his advice is dispensed based on a specific boat with its characteristics and his tolerance for risk which clearly falls on the conservative side. I share his risk philosophy of being conservative as this is supposed to be fun boating – not a race or a delivery captain mission. Each skipper is responsible for their own decisions after gathering all available data. You should make your decision based on your personal risk tolerance, your boat’s ability to handle different sea conditions, your level of competence and training, and your personal tolerance for what conditions you are willing to accept. Keep in mind that this leg is open water and is a LONG way from help if something goes wrong. VHF radio coverage is spotty in places, and cell phones simply won’t work as you go around the Everglades. I personally carry an EPIRB just in case the VHF or cell phone won’t summon help. You should be prepared to be self-sufficient for this leg or travel with a buddy boat.
If you can be patient and are not on a specific timeline, you can pick a suitable weather window and have a non-memorable open water trip to the Keys.
Dave & Nan Ellen Fuller