Theory for why north end of lake warms up first

[Ratherbfishing]

I've OFTEN heard that in the spring the north end of a lake warms up first because of the angle of the sun.  It seems to be globally accepted.  I find this to be mostly a lot of hooey.  I'm not a scientist and have not tested my theory but I believe it's for a different reason.  My theory is that in the spring, on warm days the wind is most likely going to be coming out of the south.  Warm water rises (or stays on top) and the south wind pushes this warmer water to the north end of the lake where it stacks up.  While the angle of the sun would have some effect (especially near the shore where the is the potential for shading), this would otherwise seem to be rather negligible.  What say you?

[Catt]

On Toledo Bend it's because the north end is shallower & off colored while the south end is deeper & clearer.

 

Everywhere is it's about the same maybe a couple degrees difference.

[Ratherbfishing]

5 minutes ago, Catt said:

On Toledo Bend it's because the north end is shallower & off colored while the south end is deeper & clearer.

 

Everywhere is it's about the same maybe a couple degrees difference.

Oh, yes!  Shallower, stained water will definitely warm up first.

[J Francho]

Generally the northwest end gets the most sun during the day.

 

That's the end that melt first up here, though depth has an effect, as does current.  Some of the protected bays off Lake Ontario thaw in a weird way.  I use the thaw to tell me what places are usually warmer.

[Ratherbfishing]

Just now, J Francho said:

Generally the northwest end gets the most sun during the day.

But only in the morning.  In the evening, the EAST side of the lake would get more sun.  And it's only for a relatively brief period when the land mass and trees shade the water.  I'm not trying to be argumentative. It just makes less sense to me.  And I question everything if it doesn't seem to make sense-even if it's an "accepted" truth.

[J Francho]

By evening, the air temps have cooled.  The NW side benefited from not only the sun, but warmer ambient temps.  It's not always true, but it's a general occurrence up here. 

[A-Jay]

Seems to be 'the way it is' in my neck of the woods as well.  

In fact, now that there is all season C & R for Bass here - Early season, I'm launching in any open water I can find.

Just seems to routinely be on the North End.

And wouldn't you know it, there's fish there too. 

With no reason to believe that they'd move once the rest of the lake opens up, I just keep fishing.

 

A-Jay

 

[WRB]

Most rivers in North America generally run from north to south. When these rivers are dammed to form reserviors the deep end is near the dam at the south end, the shallower water near the where rivers or creeks/stream enter towards the north end.

The sun moves east to west hitting the water on the west shore first depending on the shape of the terrian around the reservoir, the west getting slightly more direct sun light. Combine those factors and you have north-west shallower water warming faster than south-east deeper water. 

The most important factor is large areas of deep water and wind slows the water warming, large shallow areas and wind protected warms faster regardless where it's located.

Tom

[Tracker22]

In the northern hemisphere the sun is located in the southern half of the sky, thus the suns rays are projected toward the north sides of a lake.

 

[scaleface]

For what its worth , I metal detect and the south facing hillsides thaw long before the north facing ones .

[corn-on-the-rob]

Hmmm... I had always heard that this was because most cold fronts are driven from the west/north, so the winds (cooling winds) have more impact on the east/south sides since the N and W sides are more protected from that direction.

[WRB]

The northwest warming is only a general statement, each lake is different do to the terrain it's located at.

My home lake where I grew up is Big Bear lake located in the San Bernadino mountain range in SoCal with it's unique micro climate. Big Bear's dam is located at the west end the shallow water areas at the east end. The north shore is steep sloping banks, the south shore is flatter. Prevailing wind is NE meaning it's blowing towards the SW end of the lake. The deeper water doesn't get over 60 degrees until late summer, the shallower water warms to the mid 70's by summer.it's not rocket sceince to figure out where the bass and trout are located; trout in the west end, bass in the east end, spawning areas along the SE shoreline. You can't pigeon hole every lake into the one statement  that NW warms faster.

Tom

* the weather this month hasn't warmed over 60 degrees with. Low of -15 to 25 at night and 28 to 60 during the day. Big Bear is located at 7,200 feet altitude.

[Deleted account]

4 hours ago, Ratherbfishing said:

 It seems to be globally accepted.  

 What say you?

I says it's only 1/4- 1/3 globally accepted, and it is (or should be) more accepted as you go north. 

[N Florida Mike]

I have also held the opinion that the North end warms sooner because the sun is on the southern horizon.. But if you think about it , wouldn't the south end get the same sunlight unless there were trees to block the sun ?

In my little lake the extreme North and the extreme southeast part of the lake have shallow , weedy flats. Fish always seem to bed in those two areas first, which seems to indicate that the water temps there are slightly warmer , and are caused by the shallow water more than the sun's angle.

 

[WRB]

The earth being a sphere or ball the area closet to the sun is the equator with the northern and southern poles furthest away. The north is further away for rays to travel, the close area is towards the south or equator.

Tom 

[Tracker22]

6 hours ago, scaleface said:

For what its worth , I metal detect and the south facing hillsides thaw long before the north facing ones .

That is true because its a hill and not a lake. It blocks the north winds and gets the most sunlight. On a lake there will be longer shadows on the south side. Btw, that’s why most CW winter camps were on the south side of hills and north side of water.

 

[scaleface]

10 hours ago, Tracker22 said:

That is true because its a hill and not a lake.

But if a creek goes   east and west and all things even , the side getting hit by the sun should warm up faster . Early year fishing I search  for steep south facing banks . 

[38 Super Fan]

Does it really matter what causes it? In the spring I just need to know what parts of the lake are warmer. I'm sure there are several factors, and every lake and every part of each lake is different.

[SWVABass]

We fish in this fashion in the early spring, east and south facing banks tills 10 or 11, then we will switch and fish west facing banks for the remainder of the day. Also our north ends starts warming faster but there is a point in late spring it actually cools do to snow melt. At that time the mid section is warmest. On the north end we were catching spawning fish till mid June this year.

[RFSims]

7 hours ago, 38 Super Fan said:

Does it really matter what causes it? In the spring I just need to know what parts of the lake are warmer. I'm sure there are several factors, and every lake and every part of each lake is different.

What I was thinking

[Catt]

So the consensus is all the bass in the lake swim to the north end of the lake!

 

Right ?

[hawgenvy]

On 12/22/2017 at 8:32 PM, WRB said:

The earth being a sphere or ball the area closet to the sun is the equator with the northern and southern poles furthest away. The north is further away for rays to travel, the close area is towards the south or equator.

Tom 

Sorry, Tom, it's the angle of the sun, not the distance that makes a difference. The sun averages 93 million miles from the earth, and the distance difference between the equator and the northern latitudes is, percentage-wise, insignificant. As a matter of fact, the earth is 3 million miles closer to the sun in January than it is in July.

 

There are certainly many variables that influence the temperature differences between areas of a lake.  However, sun angle may be an especially important factor in more northern latitudes, in smaller lakes, in lakes where the southern shore is forested, and in lakes surrounded by hills or mountains. In such conditions the lake surface at the southern end may rarely (or never) be struck by the sun's warming rays. But if the southern end is not shaded by trees or high terrain, sun would make no difference at all, because the sun's angle is the same across all areas of the lake surface at any time.

[J Francho]

On 12/22/2017 at 2:44 PM, WRB said:

Most rivers in North America generally run from north to south.

All the tributaries connected to Lake Ontario are opposite.  In fact, the Genny is often cited as odd because it runs south to north.  It's an unusual set of circumstances, though.

[scaleface]

I could copy up  the lake and circle the area I'm talking about but dont  want to take  the time . A lake I like to fish early in the year , the upper end runs northwest .  The channel runs along  the southern side then cuts across to  the northern side . I dont know the difference in water temp but early in the year if theres a warming spell  that northern bank with the channel next to it has produced a lot of lunkers  on sunny afternoons . The southern bank usually doesnt produce anything .

[bigbill]

I was told the north end of the body of water warms up first because it gets the suns heat first, the suns heat longer. Now where are your spawning beds located. One of my local spots had a low water level. And the beds were located in the north end, small body of water.

 

on the coldest of nights my 7 cats have circled their wagons around my  Woodstove. Predators are drawn to the heat. Or warmth. Cats are very similar to bass in their actions. Lol that’s all I’m going to say about that.......he....he....

On 12/23/2017 at 9:42 PM, Catt said:

So the consensus is all the bass in the lake swim to the north end of the lake!

 

Right ?

All I’m going to say is in the spring while the rest of the body of water is cooler the north end warms up first.