Hunting the Falling Thermal

Discuss deer hunting tactics, Deer behavior. Post your Hunting Stories, Pictures, and Questions/Answers.
  • Advertisement

HB Store


User avatar
xpauliber
500 Club
Posts: 1697
Joined: Fri May 20, 2011 4:41 am
Location: Central PA
Status: Offline

Re: Hunting the Falling Thermal

Unread postby xpauliber » Fri Oct 12, 2018 4:58 am

Divergent wrote:Once there bedding starts receiving shade I move to the lower elevation. The sign in the bottom will tell you where the thermal hub is located. You’ll see rubs and possibly scrapes where they drop and go up an opposite ridge.
You can see small red dots. These mark travel route of deer dropping.
Orange is most likely where you’ll find the sign. They can check the ridges and draws to the south from the southern orange dot. They can check the southern and northwestern draws/ridges from the top orange dot.
You do not want to be setup higher in elevation than whichever hub location they’re using. If you are higher in elevation you will likely get busted by the falling thermal. You want to setup lower in elevation, so your scent is carried away from the sign. Image


Excellent. Thank you for putting this together.

Your initial setup with the thermals still rising is what most people think of for a perfect setup; thermals rising, downwind of the bedded bucks and its only a matter of waiting until primetime for them to come amble by below you and you seal the deal. Except, lots of things change during that last hour of light and your perfect setup is now perfectly sending your scent down not only directly below you but down the draw to the hub. Who knows how many deer smelled that you were up on that ridge? I wonder how many bucks I've spooked hunting these spots and not even known it.


User avatar
Divergent
500 Club
Posts: 746
Joined: Fri Sep 11, 2015 4:18 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Divergent » Fri Oct 12, 2018 5:47 am

xpauliber wrote:
Divergent wrote:Once there bedding starts receiving shade I move to the lower elevation. The sign in the bottom will tell you where the thermal hub is located. You’ll see rubs and possibly scrapes where they drop and go up an opposite ridge.
You can see small red dots. These mark travel route of deer dropping.
Orange is most likely where you’ll find the sign. They can check the ridges and draws to the south from the southern orange dot. They can check the southern and northwestern draws/ridges from the top orange dot.
You do not want to be setup higher in elevation than whichever hub location they’re using. If you are higher in elevation you will likely get busted by the falling thermal. You want to setup lower in elevation, so your scent is carried away from the sign. Image


Excellent. Thank you for putting this together.

Your initial setup with the thermals still rising is what most people think of for a perfect setup; thermals rising, downwind of the bedded bucks and its only a matter of waiting until primetime for them to come amble by below you and you seal the deal. Except, lots of things change during that last hour of light and your perfect setup is now perfectly sending your scent down not only directly below you but down the draw to the hub. Who knows how many deer smelled that you were up on that ridge? I wonder how many bucks I've spooked hunting these spots and not even known it.


No problem. And you’re right...those mature bucks won’t blow and let you know they busted you. They’ll just take a turn and head a different direction.
amesk31
Posts: 8
Joined: Wed Dec 06, 2017 12:12 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby amesk31 » Fri Oct 12, 2018 6:20 am

One thing i noticed while dropping milkweed when the falling thermal kicks in, is that my scent follows the creek down the hollow. Compared to dropping straight to the creek. At a thermal hub where all the creeks meet there should be a point where all the thermals converge and create a swirling wind. I noticed mature bucks hanging up in this area until dark. I'm guessing the only way to hunt these spot is to set up on the buck bed exit trail. I run into this problem a lot where I hunt any suggestions?
Ahawk116
Posts: 83
Joined: Fri Jun 08, 2018 3:16 am
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Ahawk116 » Fri Oct 12, 2018 8:17 am

All good stuff fellas. Particularly the diagrams divergent. Ground hunting makes a lot of sense in these situations. I’m thinking I’ll give it a go those season on a couple of particular spots. I’ve killed a few deer on the ground, but I’ve never done so being as aggressive as your talking about. Moving in for the kill after the thermal switch due to fear of bumping does and young bucks, but if your not bumping some you aren’t getting close enough.
User avatar
ghoasthunter
500 Club
Posts: 2211
Joined: Thu Jan 04, 2018 6:09 am
Location: New jersey
Status: Offline

Re: Hunting the Falling Thermal

Unread postby ghoasthunter » Fri Oct 12, 2018 8:53 am

headgear wrote:
Divergent wrote:
headgear wrote:You start to find some of the better bedding areas all have a thermal working in their favor, it is something I focus on when scouting.


How do you find them using the thermals in those situations? And, what kind of topography?


I hunt mostly swamps so take that into consideration. Lets say I have a huge swamp transition that I can scout for a couple of miles and I see a bunch of small points, some islands and too many to count lone trees that could all work for bedding. Now you have to walk the entire transition anyway to cover all of this stuff so I am scouting the whole thing. However if there are 8-10 spots I am really keying in on and a couple of those have a nice ridge or V shaped valley nearby the bedding seems to be closer to those thermal areas because the bucks can stage up after dark and smell what is up on top of the hill or smell both sides of a valley as the thermals fall down into the swamp. Or on flatter land there might be a pond, lake or beaver dam out in the swamp that will have a thermal pull so they might prefer that area over a spot a half mile away that might look better but doens't have as good of thermals.

Edit: Sometimes these thermal terrain features can also cause some swirling winds too so another reason they seem to like them.
spot on i look for and hunt the exact same setups i also find the majority of bedding is closer too the edge on the spots with flowing valleys. stand setup is critical in these areas i like too stay on wind blow side and in the swamp past the transition line where the big trees hit the brush. reason is you need to get past the turbulent air flow created buy the trees on edge that can swirl your wind and carry your scent across the entire area. you either need to get in deeper or stay back in tress 20 or 30 yards and too the down wind side. this kind of setup is way better on a wind that is cutting on a angle already. i also like too play the thermal just like the deer buy using that water too help pull my thermal always setup down stream of river crossings even the slights down hill angle will pull a thermal. sometimes this is not possible when that happens you need to make sure you can get your shot off before the deer gets into the pooling area this is just fine as long as you know the first deer exiting is going to be the right one so single lone bed setups. getting below a beaver dam or right in top can also help you pull your thermal or setting up over a ditch and shooting across the thermals may be pulling strait at deer but its going too fall in the ditch and follow the direction of the water.
THE MOST IMPORTANT TOOL A HUNTER HAS IS BETWEEN HIS SHOULDERS
User avatar
Divergent
500 Club
Posts: 746
Joined: Fri Sep 11, 2015 4:18 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Divergent » Fri Oct 12, 2018 11:54 am

amesk31 wrote:One thing i noticed while dropping milkweed when the falling thermal kicks in, is that my scent follows the creek down the hollow. Compared to dropping straight to the creek. At a thermal hub where all the creeks meet there should be a point where all the thermals converge and create a swirling wind. I noticed mature bucks hanging up in this area until dark. I'm guessing the only way to hunt these spot is to set up on the buck bed exit trail. I run into this problem a lot where I hunt any suggestions?


I haven’t run into this problem in my sets yet, but if you had two draws meeting up at just the right point I could see it happening for sure. Do you have a pic you could upload?
User avatar
Divergent
500 Club
Posts: 746
Joined: Fri Sep 11, 2015 4:18 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Divergent » Fri Oct 12, 2018 11:58 am

Ahawk116 wrote:All good stuff fellas. Particularly the diagrams divergent. Ground hunting makes a lot of sense in these situations. I’m thinking I’ll give it a go those season on a couple of particular spots. I’ve killed a few deer on the ground, but I’ve never done so being as aggressive as your talking about. Moving in for the kill after the thermal switch due to fear of bumping does and young bucks, but if your not bumping some you aren’t getting close enough.


The deer density is very low in the particular wma I hunt for most of the year. I could see it being an issue in a higher deer density area. I’ve had a lot of luck with ground hunting though. The deer that have seen or winded me will usually just run off and not blow...still not sure why it’s so different.
User avatar
jwilkstn
500 Club
Posts: 1282
Joined: Sat Aug 27, 2016 6:01 am
Facebook: https://www.facebook.com/jason.wilkerson.71
Location: The hills of Southern Middle Tennessee
Contact:
Status: Offline

Re: Hunting the Falling Thermal

Unread postby jwilkstn » Fri Oct 19, 2018 2:20 am

Divergent wrote:That makes perfect sense and I actually see the same thing when it comes to fields on top of ridges. The deer gravitate to low spots in fields because of the falling thermal advantage in the evening.


This is exactly how I killed my Kentucky buck last month. We had strong southerly winds during the day, and I expected a buck to be bedded on a prominent point that drops off a hot bean field. The point runs south to north from top to bottom, and set up perfectly for classic hill country wind to back bedding. I set up to the northeast of the point at the head of the adjacent draw but on the other side of it from the point, facing south. As expected, when the sun got low the wind died and falling thermals took control. My hope was the buck would drop off that point toward that draw where he had been watching all afternoon and felt safe, and use the falling thermals to scent check the field before entering. The gamble was whether or not he dipped low enough or crossed over the draw and got my scent falling towards him. Fortunately for me my milkweed was staying on my side of the draw for at least 50 yards and he stayed across the draw and did not drop too low. In this early season, low hunting pressure situation even nice bucks were bedding really close to the ag fields (learned this the hard way after bumping a bachelor group the first afternoon).

I don't get to mimic this scenario where I hunt here in TN, because the fields are all in the bottoms. That'll be another post... but understanding and predicting thermals no doubt were a key to that hunt despite new to me terrain and deer habits.
Not all those who wander are lost...
User avatar
bowhunter15
Posts: 2280
Joined: Wed Dec 15, 2010 3:14 pm
Facebook: https://www.facebook.com/pages/DIY-Spor ... 3136327062
Location: Minneapolis
Contact:
Status: Offline

Re: Hunting the Falling Thermal

Unread postby bowhunter15 » Sat Oct 20, 2018 5:04 am

Divergent wrote:Once there bedding starts receiving shade I move to the lower elevation. The sign in the bottom will tell you where the thermal hub is located. You’ll see rubs and possibly scrapes where they drop and go up an opposite ridge.
You can see small red dots. These mark travel route of deer dropping.
Orange is most likely where you’ll find the sign. They can check the ridges and draws to the south from the southern orange dot. They can check the southern and northwestern draws/ridges from the top orange dot.
You do not want to be setup higher in elevation than whichever hub location they’re using. If you are higher in elevation you will likely get busted by the falling thermal. You want to setup lower in elevation, so your scent is carried away from the sign. Image


Hypothetically, let's say the scenario is switched. You have a SE wind and access from the NW. In that case, shade would hit your hillside faster than the bedding. I'm assuming you'd still wait until the bedding gets shaded before making a move? I imagine theres greater risk of your scent dropping into the valley and then back up the opposite side. Do you handle those scenarios the same of find that they tend to be less effective?
User avatar
Divergent
500 Club
Posts: 746
Joined: Fri Sep 11, 2015 4:18 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Divergent » Sat Oct 20, 2018 9:32 am

jwilkstn wrote:
Divergent wrote:That makes perfect sense and I actually see the same thing when it comes to fields on top of ridges. The deer gravitate to low spots in fields because of the falling thermal advantage in the evening.


This is exactly how I killed my Kentucky buck last month. We had strong southerly winds during the day, and I expected a buck to be bedded on a prominent point that drops off a hot bean field. The point runs south to north from top to bottom, and set up perfectly for classic hill country wind to back bedding. I set up to the northeast of the point at the head of the adjacent draw but on the other side of it from the point, facing south. As expected, when the sun got low the wind died and falling thermals took control. My hope was the buck would drop off that point toward that draw where he had been watching all afternoon and felt safe, and use the falling thermals to scent check the field before entering. The gamble was whether or not he dipped low enough or crossed over the draw and got my scent falling towards him. Fortunately for me my milkweed was staying on my side of the draw for at least 50 yards and he stayed across the draw and did not drop too low. In this early season, low hunting pressure situation even nice bucks were bedding really close to the ag fields (learned this the hard way after bumping a bachelor group the first afternoon).

I don't get to mimic this scenario where I hunt here in TN, because the fields are all in the bottoms. That'll be another post... but understanding and predicting thermals no doubt were a key to that hunt despite new to me terrain and deer habits.


Good point Jason! That’s one thing I think people forget to take into account when setting up. You see a difference in opinions as far as buck travel in the evening. One person might see deer head up a draw while others might typically see them drop. Some food is up high and some down low in the bottoms. It’s all relative to the type of terrain and food that you hunt. We don’t typically see fields up high down here either.
User avatar
Divergent
500 Club
Posts: 746
Joined: Fri Sep 11, 2015 4:18 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Divergent » Sat Oct 20, 2018 9:44 am

bowhunter15 wrote:
Divergent wrote:Once there bedding starts receiving shade I move to the lower elevation. The sign in the bottom will tell you where the thermal hub is located. You’ll see rubs and possibly scrapes where they drop and go up an opposite ridge.
You can see small red dots. These mark travel route of deer dropping.
Orange is most likely where you’ll find the sign. They can check the ridges and draws to the south from the southern orange dot. They can check the southern and northwestern draws/ridges from the top orange dot.
You do not want to be setup higher in elevation than whichever hub location they’re using. If you are higher in elevation you will likely get busted by the falling thermal. You want to setup lower in elevation, so your scent is carried away from the sign. Image



Hypothetically, let's say the scenario is switched. You have a SE wind and access from the NW. In that case, shade would hit your hillside faster than the bedding. I'm assuming you'd still wait until the bedding gets shaded before making a move? I imagine theres greater risk of your scent dropping into the valley and then back up the opposite side. Do you handle those scenarios the same of find that they tend to be less effective?


Yes, there’s a greater risk of your scent falling and mixing, then shooting up the other side. You might can get away with dropping down early if there’s a strong wind overriding the thermals, but I typically only see that when a front is pushing thru down here. This could be different up north or further west. Otherwise, the wind seems to die down at dark and you risk getting busted if the opposite thermals are still rising. If you have a cold enough creek with hemlock that grow 50 yards up the hill, then you can get away with more also. The thermals seem to split along the transition. So, your thermals are still falling the closer you are to the creek, but when you get close enough to the transition they mix and rise.
HoosierBowman2425
Posts: 38
Joined: Wed Jul 18, 2018 3:22 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby HoosierBowman2425 » Sat Oct 27, 2018 10:47 am

Twenty Up wrote:I hunted a bed this past Friday and as my thermals should’ve been falling, maybe 15 minutes before dark a group of does came feeding up the creek bottom behind me. Down wind and below me. None stopped or changed behavior. So I dropped some milkweed only to have it hover in front of me for 10-15 seconds before slowly falling straight down.

Interested to see if anyone else has ever had similar experiences as mine.

In my experience I've had that happen more on flatter ground.
d_rek
Posts: 295
Joined: Tue Dec 17, 2013 7:43 am
Location: Michigan
Status: Offline

Re: Hunting the Falling Thermal

Unread postby d_rek » Sat Oct 27, 2018 12:58 pm

Observed interesting thermal tunnel from dropping thermals a few days ago on a riverbottom hunt. Hunted a large oxbow with good bedding. The oxbow itself is the lowest elevation point with a ridgeline along the norther half of the oxbow and along the S side with a 60-70ft elevation change that ultimately converges to a draw up to the mainland on the SW side of the oxbow. Wind was steady out of the N at 5-10mph walking in. When we got to the top of the north facing ridge, on the south side of the oxbow, the wind was still in our face blowing back onto the mainland. When we descended the ridge and we felt wind hitting us in the back of the head. We moved about 100 yards away from the bottom of the ridge and the wind was back in our face, though occasionally blowing back at us. I believe this was a 'thermal tunnel' from the shaded N facing ridge and N wind direction. As the N wind hit the shaded ridge which was cooler than the rest of the surrounding topography the cooling thermal kept the air current swirling at the bottom of the ridge rather than rising up and over the ridgeline.

As I moved closer to the ridge on the N side of the oxbow I observed air current taking milkweed off to the NE along the bottom of the northern ridge. I believe as the N wind air current traveled over the northern hilltop with a south facing slope the air was also being affected by falling thermals and rather than the air stay high the thermals were pulling the air toward the ground and causing the current to swirl along the bottom of the S facing ridge, though why it was travelling NE is still a mystery. Maybe it was being pulled toward the river? Not sure. There was a spot in between both the N and S ridges where wind was blowing N as it was on the mainland.

Were we setup right for the thermal effect? I'm not sure. Probably would have been better to be right on the water for that hunt so that the falling thermal would have went over the water and not swirled around on land. Still a very informative lesson on thermals.
"When a human being willfully takes the life of a wild sentient creature, in my opinion, they are then separated forever from those who have not." -Shane Mahoney
User avatar
Divergent
500 Club
Posts: 746
Joined: Fri Sep 11, 2015 4:18 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Divergent » Tue Oct 30, 2018 7:32 am

d_rek wrote:Observed interesting thermal tunnel from dropping thermals a few days ago on a riverbottom hunt. Hunted a large oxbow with good bedding. The oxbow itself is the lowest elevation point with a ridgeline along the norther half of the oxbow and along the S side with a 60-70ft elevation change that ultimately converges to a draw up to the mainland on the SW side of the oxbow. Wind was steady out of the N at 5-10mph walking in. When we got to the top of the north facing ridge, on the south side of the oxbow, the wind was still in our face blowing back onto the mainland. When we descended the ridge and we felt wind hitting us in the back of the head. We moved about 100 yards away from the bottom of the ridge and the wind was back in our face, though occasionally blowing back at us. I believe this was a 'thermal tunnel' from the shaded N facing ridge and N wind direction. As the N wind hit the shaded ridge which was cooler than the rest of the surrounding topography the cooling thermal kept the air current swirling at the bottom of the ridge rather than rising up and over the ridgeline.

As I moved closer to the ridge on the N side of the oxbow I observed air current taking milkweed off to the NE along the bottom of the northern ridge. I believe as the N wind air current traveled over the northern hilltop with a south facing slope the air was also being affected by falling thermals and rather than the air stay high the thermals were pulling the air toward the ground and causing the current to swirl along the bottom of the S facing ridge, though why it was travelling NE is still a mystery. Maybe it was being pulled toward the river? Not sure. There was a spot in between both the N and S ridges where wind was blowing N as it was on the mainland.

Were we setup right for the thermal effect? I'm not sure. Probably would have been better to be right on the water for that hunt so that the falling thermal would have went over the water and not swirled around on land. Still a very informative lesson on thermals.


There’s a lot going on in this one. It might be easier to decipher if I saw the topography.
Chuck B
500 Club
Posts: 676
Joined: Tue Oct 18, 2016 6:15 pm
Status: Offline

Re: Hunting the Falling Thermal

Unread postby Chuck B » Tue Oct 30, 2018 8:46 am

Divergent wrote:
Chuck B wrote:This is a great thread. Thermals are definitely underrated in terms of importance. I am starting to really figure them out where I usually hunt, but still have lots to learn. I have a few different spots that are just dynamite (deer moving through them every evening), but I get busted so often due to thermals. I am beginning to think that I have no chance of hunting these deer in these spots because I just can’t beat the thermals. But, I am not going to quit those spots yet tho, there has got to be a way...


I'd be interested to see how it sets up. I find the lower I can get in the late evening, the more i can get away with related to falling thermals. Of course, I have to keep in mind how far from I am from cover and what is the driving force behind the deers travel pattern.



I suck at loading pictures into this website in terms of showing you the set up via topo. You are correct though, the lower a guy can get, the better. The problem with being lower in this example though is lack of cover and the tall grass/marsh. There are just a few bare trees. I will have to try to ghillie suit it and get down below them and hope they walk by close.
If you aren't green and growing, you are ripe and rotting

Return to “Deer Hunting”

Who is online

Users browsing this forum: Huntrp, Kraftd, Nelson87, SemrushBot, Shilohspur and 3 guests