Every November the same thing happens. The boats get hauled out, the dive shop goes quiet, and somebody looks me dead in the eye and says, “Well, see you in the spring.”
No. Sit back down.
Winter is not the end of dive season. Winter is the secret season. It’s when the smart ones learn to dive while everybody else hibernates under a blanket with a streaming subscription and a family-size bag of chips.
Full disclosure: I’m getting too old to enjoy the cold-water dives. So in winter, we chase tropical water instead. But you’re not me. Yet.
Myth: “You can’t learn to dive during winter”
Myth. Busted. Most of a scuba course doesn’t happen in a lake at all. It happens in a classroom (or on your couch, if your shop offers online theory) and in a pool. Pools are heated. Pools have walls. Pools have no current and no fish judging your frog kick.
That means you can knock out the theory and the pool skills over the winter, then do your open water dives when your local water warms up, or on a warm-water trip. Find a local dive shop or instructor and ask how they handle winter courses, and whether you can finish your certification dives somewhere tropical. (Don’t ask me. I’m on a teaching break, busy enjoying the diving.)
The upside? You show up to your first open water dive already comfortable with your gear, not fumbling with your BCD like flat-pack furniture.
The bottom of the lake is the warmest seat in the house
Science time. Great for holiday parties (or getting uninvited from them).
Fresh water is densest at about 4°C (39.2°F). Colder than that, it actually gets lighter. So when a lake cools off in winter, the near-freezing water floats on top, the ice forms on the surface, and in a lake that isn’t too shallow, the water at the bottom hangs out at close to 4°C all winter long. A really cold winter or a shallow lake can change that, but that’s the basic setup.
Popular myth: lakes freeze solid from the bottom up. Nope. Ice floats because it’s less dense than liquid water. If it didn’t, every fish in Canada would be a fishsicle by February.
So yes, 4°C. Basically the inside of a beer fridge. Cozy. Bring a hood.
Meet the fish that thinks January is date night
While you’re complaining about scraping your windshield, the burbot is putting on its best slime and heading out for the party of the year.
Burbot are a freshwater member of the cod family, and they’re weird in the best way. According to the Minnesota DNR, burbot spawn in mid-winter into early spring, under the ice. They gather in pairs, or in groups of dozens or even hundreds, over sand or gravel in shallow water. No nest. No parenting. Just a big wriggling pile, a lot of thrashing, and as many as a million eggs from a single large female. The larvae hatch at about 0.15 inches long, which is one of the smallest of any freshwater fish.
They also go by nicknames like “lawyer,” “eelpout” and “poor man’s lobster.” I’m not touching the lawyer one. I like my inbox lawsuit-free.
If you want the full rundown on this slimy legend, check out our Creature Feature on the burbot.
Clear water isn’t always good news
New divers in the Great Lakes region are always amazed at how clear the water can be. Here’s the twist: some of that clarity has an invasive backstory.
Zebra mussels were first discovered in North America in the Great Lakes in 1988. Quagga mussels showed up in 1989 near Port Colborne, Lake Erie. NOAA’s Great Lakes Environmental Research Laboratory describes them as very effective filter feeders that pull particulate matter out of the water column, leaving the water very clear. Sounds great, right?
Not so fast. The same research lab links these mussels to the crash of Diporeia, a tiny, fatty, shrimp-like critter that used to be a major fish food, and reports that native mussels were completely eliminated from the open waters of Lake St. Clair.
Myth: crystal-clear water means a healthy lake. Sometimes it just means a few billion tiny freeloaders ate everything.
Those same mussels are also why we beg divers not to grab old wrecks. If you missed that rant, Stop Touching Stuff, Captain Clutchy is waiting for you.
Cold is a skill, not a punishment
Let’s be real. Cold water is serious, and learning to handle it properly is what makes you a good diver anywhere.
The US National Weather Service points out that cold shock (that big involuntary gasp when cold water hits you) can be triggered by water as warm as 25°C (77°F), and that cold shock in 10 to 15°C water can be just as severe as it is at 2°C. Their advice: dress for the water temperature, not the air temperature.
Translation for divers: exposure protection is not a fashion choice. It’s the difference between a fun dive and a dive you call after ten minutes because you can’t feel your face.
This is why a lot of cold-water divers eventually move into a drysuit. If you’re curious what that first drysuit dive feels like, read Drysuit Dilemmas: The Michelin Man Chronicles. And remember that thicker suits float more, so your weighting changes too. Our scuba weight tips will save you from the classic “why am I a cork” moment.
My rule? Anything below about 65°F (18°C) and I’m in a drysuit. With nice thermals underneath. No shame. Cold diver, cranky diver.
Why winter is a smart time to start
My honest instructor opinion (no science here, just salt):
- The pool is calm. You get to build skills without waves, surge or a boat schedule breathing down your neck.
- You arrive ready. By the time the water warms up, the gear feels familiar and your mask clearing is automatic.
- Shops are often quieter in the off-season. Ask about class sizes. Smaller groups usually mean more time with your instructor.
Your winter homework
- Sign up for a course and get the theory done while it’s dark at 5 p.m.
- Get a mask that actually fits your face. It’s the cheapest upgrade in diving and the one that matters most.
- Book pool time and practice hovering like the Jedi you were born to be.
- Read 10 Things No One Told You About Learning to Scuba Dive so nothing surprises you. Except the fish. The fish will always surprise you.
Ready to dive in? (Into a heated pool. Baby steps.)
The water doesn’t close for the season. The fish are still down there doing weird things in the cold, and the burbot are throwing a party you’re not invited to (yet).
So stop saying “see you in the spring.” Say “see you at the pool.”
Got a question about learning to dive over the off-season? Drop it in the comments. And share this post with that friend who’s been “thinking about getting certified” since 2019.
Angry Octopus out. 🐙
Sources
- USGS Water Science School, “Water Density”: usgs.gov
- Southard, J., The Environment of the Earth’s Surface (MIT), 6.6 “The Thermal Structure of Real Lakes,” via LibreTexts Geosciences: geo.libretexts.org)
- Minnesota Department of Natural Resources, “Species Profile: Burbot”: dnr.state.mn.us
- NOAA Great Lakes Environmental Research Laboratory, “Zebra & Quagga Mussel Research at NOAA’s GLERL” (2008): glerl.noaa.gov (PDF)
- NOAA National Weather Service, “Cold Water Hazards and Safety”: weather.gov
