How Cold Does It Have To Be To Go Ice Fishing ?

Ice fishing is a beloved recreational activity that’s enjoyed around the world. But if you’ve never ice fished before, you might wonder, “How cold does it have to be to go ice fishing?”


The temperature must be 32°F (0°C) or lower to go ice fishing on a freshwater lake and 28°F (-2.2°C) or lower for seawater ice fishing. The ideal temperature range for ice fishing is 20°F to 32°F (-6.6°C to 0°C). Going ice fishing in the morning after a hard freeze is best.


This article will explore the temperature at which water freezes, ensuring that you enjoy an ice fishing session at the ideal temperature. We’ll also discuss a few safety tips to ensure your fishing trip goes smoothly.

The Temperature at Which Water Freezes

Understanding the temperature at which water freezes is the first step toward knowing if it’s cold enough to go ice fishing. Fortunately, the freezing point of water is relatively consistent, even at varying altitudes.


Water freezes at about 0°C (32°F), turning from a liquid into a solid state. However, the depth of a water body can significantly impact the thickness of the ice development and its freezing point. 


For example, individual water molecules can sometimes have a freezing point of -42°F (-41°C)!

How Water Depth Affects Ice Formation

Very few lakes and deep rivers fully freeze during the winter and instead remain liquid beneath an icy surface. This reaction is what allows anglers to catch fish on frozen water bodies.


Generally, shallow pools of water freeze more completely than deep lakes. This is why sheets of ice might develop near a shoreline during winter, but liquid waves may still roll in from further out to sea.


Still, the ice around a frozen lake shore is often thinner and more prone to cracking than the ice near the middle of the lake. That’s because there’s more available water in the deeper areas of a water body, often resulting in a thicker layer of ice. 


But while you might be tempted to believe that thicker ice layers mean safer fishing, it’s crucial to note that extremely cold temperatures can make ice fishing almost impossible.

Extreme Cold Can Prohibit You From Ice Fishing

Ice fishing when the temperature is below freezing can offer a little peace of mind, as it often means the surface ice is thick and relatively stable. 


But when temperatures plummet to below 20°F (-6.6°C), ice can form rapidly on exposed liquid water, making it challenging to keep the fishing hole exposed and accessible. As such, it might be best to go ice fishing when temperatures are just at 20°F (-6.6°C). 


This point provides maximum ice stability without jeopardizing your access to the water beneath the ice. The primary exception to this rule would be seawater ice fishing, as saline water freezes at a lower temperature than fresh water.

How Water Salinity Affects Ice Formation

Freshwater might freeze at around 32°F (0°C), but salt water has a lower freezing point of about 28°F (-2.2°C). This is why it’s often unsafe to attempt ice fishing on the sea when temperatures are at the standard water freezing point.


Salt inhibits ice formation by squeezing between water molecules, preventing them from locking together to form a solid. This reaction is why salt is often added to paved roads and sidewalks during the winter, as the salt keeps the road from icing over completely, making it safer for cars and pedestrians.


So, if you’re thinking of ice fishing on a salty or brackish water body, you’ll want to ensure that temperatures are consistently at or below 28°F (-2.2°C). 

Choosing the Right Time To Go Ice Fishing

Now that you know how cold it has to be to go ice fishing, when is the best time to go ice fishing?


Generally, the best time to head out onto the ice and cast your line is directly after a hard freeze, but before a heavy snowfall. This window of time is ideal for ice fishing, as the ice will be visible, so you can see cracks and potential hazards, and be relatively stable.


After all, while the icy surface of a lake might look stable, it’s actually in constant motion. 


During the day, the surface can heat up slightly beneath sunlight, causing it to expand slightly. But when the night falls, the ice contracts, pulling together as temperatures plummet.


This expansion and contraction process causes cracks to form along the surface of the ice sheet, posing dangers to anglers. Falling through the ice can be fatal, which is why anglers should adhere to safety guidelines when ice fishing.

How To Stay Safe When Ice Fishing

Heavy winter clothing and fishing gear are necessary when ice fishing, but the extra weight of these items can increase the risk of ice cracks. When ice cracks and falls into the liquid water below, you and your gear will follow suit.


Drowning is the most significant risk associated with falling into the water beneath an ice sheet. That’s because the body reacts to a sudden icy plunge by forcing a sudden gasp, which is called the cold shock response


If your head happens to be underwater when this happens, your lungs can fill with ice-cold water. Naturally, hypothermia is another potential consequence of falling through the ice. 


Fortunately, both dangers are avoidable, especially when you take precautions like:


  • Avoid ice fishing on rivers.
  • Don’t go fishing after heavy snowfall.
  • Fish in a group.
  • Measure ice thickness before setting up your gear.
  • Wear a lifejacket.
  • Bring a change of clothing and footwear.

Final Thoughts

The ideal temperature for ice fishing varies depending on the type of water you want to fish over. Freshwater freezes at 32°F (0°C), while saltwater freezes at 28°F (-2.2°C). Still, ice fishing when temperatures are below 28°F (-2.2°C) but above 20°F (-6.6°C)  might be best.


Ice fishing directly after a hard freeze, but before heavy snowfall, is ideal, as the ice sheets haven’t had time to expand and contract, a process responsible for ice crack formation. 


No matter when you go ice fishing, practice safety guidelines like measuring the ice thickness and wearing a lifejacket.

Scroll to Top