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Mastering Thermals: Predicting Winds for Successful Bowhunting

Have you ever found yourself in the perfect hunting spot, only to have a deer blow and slip away due to a sudden shift in the wind? Understanding thermals – the invisible currents of air that can carry drift straight to where you are expecting a deer to come from – is a game-changer in the world of bowhunting. It’s the secret weapon that separates the occasional lucky shot from the consistently successful hunter. In this article, we’re going to unravel the mystery of thermals, turning this fickle force of nature into your trusted ally on your next hunting adventure. So, buckle up and get ready to transform your bowhunting skills from good to exceptional!

Understanding Thermals

If you’re new to the world of hunting, or even if you’re a seasoned pro, the concept of thermals might be a bit foreign. But don’t worry, we’re here to break it down for you in a way that’s easy to understand and apply to your hunting strategy.

Definition and Explanation of Thermals

Thermals, in the simplest terms, are columns of rising or falling air. They’re created by the heating and cooling of the Earth’s surface. When the ground heats up, it warms the air above it. This warm air is lighter than the surrounding cooler air, so it rises, creating an updraft, or a thermal. Conversely, when the ground cools, it chills the air above it. This cooler air is denser and heavier than the surrounding warmer air, so it sinks, creating a downdraft, or a negative thermal. 

The Impact of Changing Temperatures on Thermals

Changing temperatures throughout the day significantly impact thermals. In the morning, as thermals begin to rise they usually can last for several hours, typically until the afternoon when the sun is at its peak. At this point, there’s often a lull in thermal activity as the temperatures level out. As the day cools into the evening, downdrafts begin to form, typically lasting until the next morning when the cycle starts again.

The Difference Between Updrafts and Downdrafts

The primary difference between updrafts and downdrafts is the direction in which the air is moving. Updrafts occur when warm air rises, while downdrafts occur when cool air falls. This is important for hunters to understand because these air movements can carry your scent towards or away from whatever it is you are hunting.

How Terrain and Topography Affect Thermals

Terrain and topography regardless of public or private land can have a significant impact on thermals. In hilly or mountainous areas, thermals can be more potent and predictable due to the elevation changes. For example, warm air rising up a hillside can create a strong updraft, while cool air sinking into a valley can create a strong downdraft. Even in flatter areas, features like bodies of water, vegetation, and man-made structures can influence thermal activity.

Understanding thermals is a crucial part of successful hunting. By knowing how and why the air moves as it does, you can better predict where your scent will go, helping you stay undetected. So, the next time you’re out in the field, take a moment to consider the thermals and use them to your advantage. Get to know how they act in an area you plan to hunt.

Thermals and Deer Behavior

Understanding how deer interact with and utilize thermals can significantly improve your hunting success. Deer, especially mature bucks, are incredibly savvy creatures that have adapted to use their environment, including thermals, to their advantage. 

How Deer Use Thermals to Their Advantage

Deer, particularly whitetails, have an extraordinary sense of smell, which is their primary defense mechanism. They use this sense to detect danger, including the scent of hunters. Thermals play a significant role in how deer detect these scents.

During periods of rising thermals (updrafts), deer often position themselves on higher terrain. This allows them to detect the scent of predators or hunters that is being carried upward by the warm air. Conversely, during periods of falling thermals (downdrafts), deer often move to lower terrain where the cooler air is sinking, bringing with it the scent of any threats from above. Knowing this can help you identify area’s you plan to hunt and how to get in and out of them remaining undetected.

The Impact of Thermals on Deer Movement and Behavior

Thermals can greatly influence deer movement and behavior. For example, deer often adjust their bedding locations based on thermal activity. They may choose to bed on south-facing slopes during the colder months because these areas receive more sunlight and thus have stronger rising thermals. This helps them detect any danger from below.

Similarly, deer often adjust their travel routes based on thermal activity. They may choose to move along ridges or downwind sides of hills during periods of rising thermals, allowing them to detect scents from both the area below them and the area upwind.

How Deer Use Thermals During Different Times of the Day

Deer behavior changes throughout the day in response to the shifting thermal currents. In the morning, as thermals rise, deer are likely to be found on higher ground so use this knowledge to your advantage in your morning hunts.

In the late afternoon and evening, as the ground cools and thermals begin to fall, deer typically move to lower ground. Here, the sinking cool air carries the scent of predators from higher ground down to them. This is why you’ll often see deer entering fields and open areas from lower points in the late afternoon and evening. So be aware of that and possibly have a stand in that location for evening hunts. Understanding how deer use thermals to their advantage can help you predict their movements and behavior, making you a more successful hunter. 

Using Thermals to Your Advantage

As a hunter, understanding thermals is like having a secret weapon. It can give you an edge in predicting deer movement, choosing the best hunting spots, and ultimately, increasing your chances of a successful harvest. Let’s explore how you can use thermals to your advantage, especially if you’re new to hunting.

How to Use Thermals to Predict Deer Movement

One of the key ways to use thermals in hunting is to predict deer movement. As we’ve discussed, deer adjust their behavior based on thermal activity. They position themselves on higher or lower terrain depending on whether the thermals are rising or falling. This behavior can help you anticipate where deer are likely to be at different times of the day.

Remember, these are general patterns and can vary based on local conditions and individual deer behavior. But understanding these patterns can give you a starting point in predicting deer movement.

Strategies for Hunting in Different Thermal Conditions

Different thermal conditions require different hunting strategies. Here are some strategies for hunting in rising and falling thermals:

Hunting in Rising Thermals (Morning to Early Afternoon): During this period, consider setting up your stand or blind on higher ground. This will help keep your scent above the deer. Be mindful of the wind direction as well. You want to position yourself so that the wind and rising thermals carry your scent away from where you anticipate the deer to be.

Hunting in Falling Thermals (Late Afternoon to Evening): As thermals begin to fall, consider moving to lower ground. This can help keep your scent below the deer. Again, be mindful of the wind direction. You want it to carry your scent away from the deer’s anticipated location.

Remember, thermals can be influenced by local conditions such as bodies of water, vegetation, and terrain. Spend time in your hunting area to understand how these factors affect thermal activity.

The Importance of Understanding Wind and Thermals in Choosing Hunting Spots

Choosing the right hunting spot is crucial for a successful hunt. Understanding wind and thermals can greatly assist in this decision. When scouting for hunting spots, consider how the wind and thermals move through the area. Look for areas where deer are likely to move based on thermal activity. 

Also, consider how your scent will travel based on the wind and thermal activity. You want to position yourself so that your scent is carried away from the deer’s anticipated location. This might mean setting up your stand or blind downwind of a trail, feeding area, or bedding area.

An easy trick hunters use for seeing thermals and the direction they are going is milkweed. Milkweed is a popular tool among deer hunters for detecting thermals and wind direction due to its lightweight and buoyant properties. When a hunter releases a tuft of milkweed fluff into the air, it gets carried along by the slightest breeze or thermal current, providing a visual representation of the air movement.

Here’s why it’s particularly useful:

  1. Sensitivity: Milkweed fluff is extremely light and sensitive to even the slightest air currents. This makes it an excellent indicator of subtle wind shifts and thermal currents that might not be noticeable otherwise.
  2. Buoyancy: Milkweed fluff tends to float and drift slowly, rather than quickly falling to the ground. This allows hunters to observe the direction and speed of the wind or thermal over a longer period and distance.
  3. Visibility: The bright white color of milkweed fluff makes it easy to see against most backgrounds, allowing hunters to track its movement easily.

By observing the direction and speed at which the milkweed fluff moves, hunters can gain a better understanding of how their scent is likely to travel and adjust their position or strategy accordingly. This can be especially useful when hunting in hilly or mountainous terrain, where thermals can have a significant impact on scent distribution.

Advanced Strategies for Using Thermals

For those of you who have a solid understanding of thermals and have already used this knowledge in your hunting strategies, it’s time to take it to the next level. 

How to Use “Just-Off” Winds and Thermals

One advanced strategy involves using “just-off” winds and thermals. This refers to positioning yourself in a way that your scent drifts just outside of the deer’s expected travel path or bedding area. It’s a risky move, as you’re essentially playing on the edge of the deer’s scent detection zone, but when executed correctly, it can pay off significantly.

The key to this strategy is understanding the specific wind and thermal patterns in your hunting area and the behavior of the deer you’re pursuing. You’ll need to position yourself so that the wind and thermals carry your scent in a direction that’s close to, but not directly into, the area where you expect the deer to be. This can allow you to remain undetected while still being close enough for a shot.

The Role of Terrain Features in Thermal Strategies

Terrain features play a significant role in how thermals behave, and understanding this can greatly enhance your hunting strategy. For example, saddles in ridgelines, ravines separating hills, and other pinch points in the terrain can create unique thermal patterns.

Deer often use these terrain features to their advantage, moving through these areas where they can catch the scent of predators from multiple directions. As a hunter, you can use this knowledge to anticipate deer movement and position yourself accordingly.

In addition, terrain features can create thermal tunnels or funnels where rising or falling thermals are concentrated. Identifying these areas can give you an edge, as they often serve as preferred travel routes for deer, especially during periods of thermal transition.

The Importance of Having Multiple Stand Sites

Having multiple stand sites is another advanced strategy that can increase your success. Personally I use a tree saddle which gives me the option to set up in any tree not needing pre set stands. However, if that’s not an option for you, hanging different stand will be advantageous for you under different wind and thermal conditions, and having a variety of options allows you to adapt to the conditions of any given day.

When choosing stand sites, consider how the wind and thermals move through the area. You’ll want sites that allow you to hunt effectively in both rising and falling thermals, and in different wind directions. Also, consider the deer’s likely travel routes and how your scent will be carried from each stand site.

Having multiple stand sites also allows you to avoid over-hunting a single area, which can make deer wary and less likely to frequent the area. By rotating between stand sites, you can keep the pressure low and the deer less aware of your presence.

Remember, these advanced strategies require a deep understanding of thermals and deer behavior, as well as careful observation and adaptation to your specific hunting area. But with practice and patience, these strategies can greatly enhance your hunting success.

Predicting and Monitoring Thermals

As you become more experienced in hunting, you’ll realize that success often hinges on your ability to predict and monitor thermals. This involves understanding the factors that influence thermals, using technology to aid in monitoring, and spending time in the field to get a feel for the land you’re hunting. 

How to Predict Changes in Thermals

Predicting changes in thermals primarily involves understanding the factors that influence them. The most significant of these is the sun. Therefore, you can generally predict that thermals will rise in the morning and fall in the evening.

However, other factors can also influence thermals. For example, cloud cover can reduce the warming effect of the sun, which can lessen the strength of rising thermals. Similarly, a sudden drop in temperature can cause thermals to fall more quickly.

In addition, the local terrain can influence how thermals behave. For example, south-facing slopes may warm more quickly and create stronger rising thermals in the morning compared to north-facing slopes. Understanding these nuances can help you predict how thermals will behave in your specific hunting area.

The Role of Weather Apps in Monitoring Wind Currents and Thermals

In today’s digital age, technology can be a valuable tool in your hunting arsenal. Weather apps, in particular, can be incredibly useful for monitoring wind currents and thermals.

Apps like HuntStand, for example, offer features that allow you to monitor, record, and track wind currents. This can help you understand how the wind is likely to carry your scent in your hunting area. Some apps also offer topographic maps, which can help you understand how the terrain might influence thermals.

While these apps can’t directly monitor thermals, they can provide valuable information that can help you predict thermal behavior. For example, by monitoring the temperature throughout the day, you can anticipate when thermals are likely to rise or fall.

The Importance of Scouting and Understanding the Land You Plan to Hunt

While understanding the theory behind thermals and using technology to monitor conditions are important, there’s no substitute for spending time in the field. Scouting the land you plan to hunt is crucial for understanding how thermals behave in that specific area.

When scouting, pay attention to how the wind and thermals move through the area at different times of the day. Notice how the terrain influences this movement. Look for signs of deer movement and try to understand how the deer are using the wind and thermals to their advantage.

Over time, you’ll start to develop a feel for the land and how the thermals behave. This understanding, combined with your knowledge of thermals and the use of technology, can greatly enhance your ability to predict and monitor thermals, ultimately leading to more successful hunts.


As we draw this article to a close, it’s clear that the art of bowhunting is as much a science as it is a sport. The invisible dance of thermals, swirling and shifting with the rhythm of the day, plays a pivotal role in the delicate balance between hunter and hunted. Understanding and harnessing the power of these elusive air currents can transform your hunting experience, elevating you from a casual enthusiast to a master of the hunt.

We’ve journeyed through the fundamentals of thermals, exploring their creation and behavior, and delving into the profound impact they have on deer movement. We’ve uncovered strategies to use thermals to our advantage, from predicting deer behavior to selecting the ideal hunting spots. For our seasoned hunters, we’ve delved into advanced strategies, pushing the boundaries of our understanding and application of thermals.

But the pursuit of knowledge is a never-ending journey. The world of thermals is dynamic and ever-changing, much like the wilderness we love to explore. As hunters, we are perpetual students of nature, always learning, always adapting. I encourage you to continue this journey of learning, to experiment with thermals, to observe their effects on your hunts, and to share your experiences with the hunting community.

Remember, every hunt is an opportunity to learn, to grow, and to connect with the natural world. So, as you step into the wilderness, bow in hand, feel the wind on your face, watch the leaves flutter in the thermals, and know that you carry with you a deeper understanding of this incredible force of nature.

Here’s to your next hunt. May it be guided by knowledge, filled with adventure, and crowned with success. If you are interested in saddle hunting after reading this be sure to check out more of our articles on how to get started and any gear you may need.  Happy hunting!


In the digital age, technology has become a valuable ally for hunters. From weather tracking to topographic mapping, there’s an app or tool out there that can enhance your understanding and use of thermals in bowhunting. Let’s explore some recommended resources that can assist you on your hunting journey.

Recommended Apps and Tools for Understanding and Tracking Thermals

HuntStand: This app offers a range of features including weather tracking, wind direction, and topographic mapping. While it doesn’t directly track thermals, it provides valuable information that can help you predict thermal behavior.

onX Hunt: This app provides detailed topographic maps, which can help you understand how the terrain in your hunting area might influence thermals. It also offers a feature that shows wind direction and speed.

Weather Underground: This app provides detailed weather information, including temperature changes throughout the day, which can help you anticipate when thermals are likely to rise or fall.

GoHunt: While not an app, this online platform offers detailed information and tools for hunters, including topographic maps and weather information.

The advancement of these apps and tools has made it easier than ever to access real-time information about weather and terrain conditions, which are crucial for understanding and predicting thermals. By using these resources, you can make more informed decisions and increase your chances of a successful hunt.

Additional Reading and Resources for Mastering Thermals in Bowhunting

In addition to apps and tools, there are numerous books, articles, and online resources that can enhance your understanding of thermals. Here are a few recommendations:

Mapping Trophy Bucks by Brad Herndon: This book offers valuable insights into using topographic maps to predict deer movement, which is closely tied to thermal activity.

Precision Bowhunting: A Year-Round Approach to Taking Mature Whitetails by John and Chris Eberhart: This book provides a comprehensive guide to bowhunting, including a section on using wind and thermals.

QDMA (Quality Deer Management Association): This organization’s website offers a wealth of articles and resources on all aspects of deer hunting, including understanding and using thermals.

Bowhunter-ed and Hunter-ed: These online platforms offer state-specific hunter education courses, some of which include information on understanding and using wind and thermals in hunting.

Remember, mastering thermals in bowhunting is a journey of continuous learning. By leveraging the power of technology and investing time in further education, you can enhance your skills and become a more successful hunter.