The effect of weather on shot distances

Su Campu

Different weather conditions have a bigger effect on golf shots than you might think, and is something that should be considered at different times of the year.

Consider two scenarios - a cold dry frosty morning in winter (say 0 °C, RH 80%, with frost on the ground) and a warm humid afternoon in summer (say 25 °C, RH 70%, strong sunshine). Assume no wind in both cases and we're playing the same course (so same altitude, say near sea level).

Air density and ball temperature are the two factors directly affecting the flight of the ball (neglect the effects on the player and club shaft!).

Air density is dependent on air temperature, specific humidity, pressure and altitude. Assume altitude and pressure are the same in both scenarios, so only temperature and specific humidity are different (by specific humidity I mean the actual amount of water vapour in the air (grams per kilo of air) as opposed to relative humidity, which is the percentage of water vapour in the air compared to the maximum it could hold at that temperature (warmer air can hold more water vapour than colder air). The air density for the two scenarios is

Winter 1.286 kg/m³
Summer 1.170 kg/m³

The aerodynamic drag on a golf ball is directly related to the air density, with lower density producing lower drag. So the percentage difference between the drag on the ball is just the difference in densities (i.e. around 10%). That means a 10 yard difference for every 100 yards of distance, so a wintertime carry of 220 yards could be around 245 yards in summer, all other things equal.

But all other things aren't equal. The temperature of the ball has a big effect. They say the optimum temperature of a golf ball is around 27 °C, as that's where the compression is greatest. It takes around 6 hours for the ball to fully warm to this temperature to its core, so storing it indoors overnight prior to a round can gain you a few yards.

During a round of golf the ball spends most of its time lying on the ground, and is only in the air a tiny fraction of the time. Therefore ground temperature will determine its temperature. In winter, with frost on the ground (assume they didn't close the course!) the ground temperature could be as low as -10 °C and temperature of the ball will fall quickly during the round, and will be at its coldest on the 18th. You could of course keep a ball in your pocket and alternate balls every hole to slow down this cooling process but it will still cool down overall. In summertime, with strong sunshine, the ground could be 30 °C or more, so the ball should hold its temperature right throughout the round. As the core materials are more elastic at this temperature, plus the ground will probably be harder, the bounce and roll will be much bigger than in winter.

So we have the 10% increase due to different air densities plus the effect of a warmer ball and harder ground (not to mention the physical state of the player). We could be looking at 20-30% longer drives and using around 1-2 irons less in summer versus winter. The longest distances will be in warm muggy low pressure systems while the shortest will be in early morning in cold dry high pressure systems.

Of course in reality we get a much smaller spread in contitions throughout the year, with most rounds probably played between 10-20 °C, but it might be interesting to compare your distances now to those in a few months' time (assuming wind conditions are the same).

k.p.h

Great post SC, very interesting.

Su Campu

If we take it a step further and compare say the Irish Open (summer scenario above) to the USPGA in a hot and humid August in the southern states (say 35 °C, 70% RH), then the the ball will carry a further 4% in the US (density 1.125 kg/m³). If the Irish Open were at say a more normal 18 °C then this difference would be around 6.5%.

newport2

But all other things aren't equal. The temperature of the ball has a big effect. They say the optimum temperature of a golf ball is around 27 °C, as that's where the compression is greatest. It takes around 6 hours for the ball to fully warm to this temperature to its core, so storing it indoors overnight prior to a round can gain you a few yards.

Either Ken Brown or Mark James - can't remember which - said on live Tv commentary of The Open a few years ago that they used to soak their balls in warm water for a few hours before playing on a cold day. The whole commentary box went silent............


Good post

irish bloke

newport2 wrote: »

Either Ken Brown or Mark James - can't remember which - said on live Tv commentary of The Open a few years ago that they used to soak their balls in warm water for a few hours before playing on a cold day. The whole commentary box went silent............


Good post

Very good:D. Sounds like something Peter Alliss would say...

BrianD3

Good post. I knew or suspected some of this already but that post sums it up and explains it nicely.

Just on the 27 degrees for ideal ball compression, is there a a source for this. Is it possible that this figure is for wound rubber golf balls which are now obsolete but were very common up until about 15 years ago.

Temperature can have a noticable effect on rubber. There is a fella on youtube called Jorg Sprave who has done some experiments on the effect of temperature on rubber elasticity, not in relation to golf balls but in relation to rubber powered slingshots
http://www.youtube.com/watch?v=f3t2_AX8HUk

Su Campu

BrianD3 wrote: »

Good post. I knew or suspected some of this already but that post sums it up and explains it nicely.

Just on the 27 degrees for ideal ball compression, is there a a source for this. Is it possible that this figure is for wound rubber golf balls which are now obsolete but were very common up until about 15 years ago.

Temperature can have a noticable effect on rubber. There is a fella on youtube called Jorg Sprave who has done some experiments on the effect of temperature on rubber elasticity, not in relation to golf balls but in relation to rubber powered slingshots
http://www.youtube.com/watch?v=f3t2_AX8HUk

Here's the source, from Golf.com.

Ball cores are made of different typs of synthetic elastomers, which all have varying degrees of elasticity. Every substance has a level of elasticity, which are given by its bulk and storage moduli. In general the lower the temperature the more rigid the material becomes, towards its glass transition temperature, which is where it becomes brittle.

stockdam

I thought everybody knew that shots carried about 10% to 20% or so less in winter plus there's no run on the ball in winter which makes the total difference even worse.

You can even notice the difference on a summer's evening if it starts to get colder.

The_Kew_Tour

I would say I go down up to 3 clubs in winter time compared to summer with Long Irons.

Mr. Larson

The_Kew_Tour wrote: »

I would say I go down up to 3 clubs in winter time compared to summer with Long Irons.

If we're talking 'carry' only it's 2 clubs for me. Played 2 clubs different from the same spot over past few weeks, flat calm both times so wind wasn't a factor. The air just felt different and the shots just appeared different, visually. Don't know how much subconscious had to do with it but I think your head can just figure it out and the shot looks different in different air conditions. That's my experience anyway. I don't personally find myself making mental notes about temperature except for say, late in the evening.

Mr. Larson

Jabberwocky wrote: »

The_Kew_Tour wrote: »

I would say I go down up to 3 clubs in winter time compared to summer with Long Irons.

If we're talking 'carry' only it's 2 clubs for me. Played 2 clubs different from the same spot over past few weeks, flat calm both times so wind wasn't a factor. The air just felt different and the shots just appeared different, visually. Don't know how much subconscious had to do with it but I think your head can just figure it out and the shot looks different in different air conditions. That's my experience anyway. I don't personally find myself making mental notes about temperature except for say, late in the evening.

Also I enjoyed watcing the opening of the last Ryder Cup at Celtic Manor, cold damp morning and they looked to be all carrying the ball about 250 off the tee. Was nice to see .

The_Kew_Tour

Jabberwocky wrote: »

If we're talking 'carry' only it's 2 clubs for me. Played 2 clubs different from the same spot over past few weeks, flat calm both times so wind wasn't a factor. The air just felt different and the shots just appeared different, visually. Don't know how much subconscious had to do with it but I think your head can just figure it out and the shot looks different in different air conditions. That's my experience anyway. I don't personally find myself making mental notes about temperature except for say, late in the evening.

Yes it's mostly 1 or 2 for me, but add in wind and then it's 3 on longer irons.(if strong and against me)

I looking forward to middle March when the mats go and its the time of year when can start to play Golf without actually been blown off the course all the time.

I love Links Golf but only in Summer when its milder and when it is windy least it's warmer then now.

irish bloke

stockdam wrote: »

I thought everybody knew that shots carried about 10% to 20% or so less in winter

I actually had no idea this was the case.. Thought I just wasn't getting them as good.

Redzah

Su Campu wrote: »

Different weather conditions have a bigger effect on golf shots than you might think, and is something that should be considered at different times of the year.

Consider two scenarios - a cold dry frosty morning in winter (say 0 °C, RH 80%, with frost on the ground) and a warm humid afternoon in summer (say 25 °C, RH 70%, strong sunshine). Assume no wind in both cases and we're playing the same course (so same altitude, say near sea level).

Air density and ball temperature are the two factors directly affecting the flight of the ball (neglect the effects on the player and club shaft!).

Air density is dependent on air temperature, specific humidity, pressure and altitude. Assume altitude and pressure are the same in both scenarios, so only temperature and specific humidity are different (by specific humidity I mean the actual amount of water vapour in the air (grams per kilo of air) as opposed to relative humidity, which is the percentage of water vapour in the air compared to the maximum it could hold at that temperature (warmer air can hold more water vapour than colder air). The air density for the two scenarios is

Winter 1.286 kg/m³
Summer 1.170 kg/m³

The aerodynamic drag on a golf ball is directly related to the air density, with lower density producing lower drag. So the percentage difference between the drag on the ball is just the difference in densities (i.e. around 10%). That means a 10 yard difference for every 100 yards of distance, so a wintertime carry of 220 yards could be around 245 yards in summer, all other things equal.

But all other things aren't equal. The temperature of the ball has a big effect. They say the optimum temperature of a golf ball is around 27 °C, as that's where the compression is greatest. It takes around 6 hours for the ball to fully warm to this temperature to its core, so storing it indoors overnight prior to a round can gain you a few yards.

During a round of golf the ball spends most of its time lying on the ground, and is only in the air a tiny fraction of the time. Therefore ground temperature will determine its temperature. In winter, with frost on the ground (assume they didn't close the course!) the ground temperature could be as low as -10 °C and temperature of the ball will fall quickly during the round, and will be at its coldest on the 18th. You could of course keep a ball in your pocket and alternate balls every hole to slow down this cooling process but it will still cool down overall. In summertime, with strong sunshine, the ground could be 30 °C or more, so the ball should hold its temperature right throughout the round. As the core materials are more elastic at this temperature, plus the ground will probably be harder, the bounce and roll will be much bigger than in winter.

So we have the 10% increase due to different air densities plus the effect of a warmer ball and harder ground (not to mention the physical state of the player). We could be looking at 20-30% longer drives and using around 1-2 irons less in summer versus winter. The longest distances will be in warm muggy low pressure systems while the shortest will be in early morning in cold dry high pressure systems.

Of course in reality we get a much smaller spread in contitions throughout the year, with most rounds probably played between 10-20 °C, but it might be interesting to compare your distances now to those in a few months' time (assuming wind conditions are the same).

Interesting post Su. I would've thought around 10% to be right so its good that its backed up by the science. If boards members played in the US they'd be smacking it 330 of the tee in those conditions

Su Campu

Redzah wrote: »

Interesting post Su. I would've thought around 10% to be right so its good that its backed up by the science. If boards members played in the US they'd be smacking it 330 of the tee in those conditions

My 291-yard average was taken over the depths of winter! :pac::P

Almaviva

The above shows the dramatic effect the weather does have on the flight of a golf ball. But to an extent, you can allow for these - they are relatively predictable influences on ball flight after it has been hit by the club.

But as we all know, getting club and ball contact correct in the first place is the really difficult part of playing golf. Bringing the clubface into the ball at the right speed, path, and acceleration, and on top of that, timing it all to the optimum flexing of the shaft is an extremely small target. And very easily upset. Even by changes in the swing weight of your club if playing in the rain. Most golfers are unable (and even unaware of the need) to change their swing to allow for this effect - meaning that in the rain, they are less likely to achieve precise club-ball contact. Never mind the effect the weather will have on the ball after it is struck.

I know I am poor at it, and playing in the rain throws my timing off for this reason. I can even struggle sometimes on a morning where the dew is still on the grass, but drying the clubhead with a towel, and hovering the club above the grass to keep it dry, find it more manageable. Unfortunately of course, that is no help in the rain.

The_Architect

So I don't really agree with distance aids.

I would like to see a 150 yard marker in the ground and nothing else. No GPS, no laser finder.

This original post is part way why distance aids are not needed. Add in wind conditions, the firmness of the ground and elevation changes and the idea of a 10 handicap golfer wanting to know the distance from the flag to the nearest yard or two is faintly ridiculous.

Play be eye and feel and get on with it.

Rikand

good post su.

was playing today and we had a fella who had one of those distance measuring devices. I never thought about it before, but it was interesting to see the differences in distance that I just subconsciously work down through the winter. Picking a 7-iron out for a 140 yard shot which normally I'd use from 165 in the summer.

it really makes you think

onedmc

Redzah wrote: »

Interesting post Su. I would've thought around 10% to be right so its good that its backed up by the science. If boards members played in the US they'd be smacking it 330 of the tee in those conditions

I think the science is a little sketchy.

Perhaps the drag due to air may increase by 10% but the significant force causing it to stop is gravity. Air making up say 10% so we have 10%of10%which in the example would be 1 meter.

Also not sure about an rh of 80% after a frosty night.

Su Campu

onedmc wrote: »

I think the science is a little sketchy.

Perhaps the drag due to air may increase by 10% but the significant force causing it to stop is gravity. Air making up say 10% so we have 10%of10%which in the example would be 1 meter.

Also not sure about an rh of 80% after a frosty night.

There's nothing sketchy about the science. Gravity is the same no matter what time of year and is therefore a constant in the calculation and makes no contribution to the difference in flights.

And I'm not sure what you mean about the RH. You can have RH of 80% at any temperature. It's just that at low temperatures 80% means there is less water vapour in the air than 80% at a higher temperature.

Believe me, the science is correct.

Su Campu

Almaviva wrote: »

The above shows the dramatic effect the weather does have on the flight of a golf ball. But to an extent, you can allow for these - they are relatively predictable influences on ball flight after it has been hit by the club.

But as we all know, getting club and ball contact correct in the first place is the really difficult part of playing golf. Bringing the clubface into the ball at the right speed, path, and acceleration, and on top of that, timing it all to the optimum flexing of the shaft is an extremely small target. And very easily upset. Even by changes in the swing weight of your club if playing in the rain. Most golfers are unable (and even unaware of the need) to change their swing to allow for this effect - meaning that in the rain, they are less likely to achieve precise club-ball contact. Never mind the effect the weather will have on the ball after it is struck.

I know I am poor at it, and playing in the rain throws my timing off for this reason. I can even struggle sometimes on a morning where the dew is still on the grass, but drying the clubhead with a towel, and hovering the club above the grass to keep it dry, find it more manageable. Unfortunately of course, that is no help in the rain.

I must pull you up on the playing in the rain idea. With the forces at play in a golf swing, the presence of a few micrograms of water on the club is not something that requires a swing compensation. I think that if you play badly in the rain then it is because your mind is distracted by the rain and therefore your normal swing thoughts are disrupted. I would recommend that you forget about the rain and especially about hovering the club as this IS something that will feck up a shot!

Su Campu

The_Architect wrote: »

So I don't really agree with distance aids.

I would like to see a 150 yard marker in the ground and nothing else. No GPS, no laser finder.

This original post is part way why distance aids are not needed. Add in wind conditions, the firmness of the ground and elevation changes and the idea of a 10 handicap golfer wanting to know the distance from the flag to the nearest yard or two is faintly ridiculous.

Play be eye and feel and get on with it.

Again I'm not sure what you mean by there's no need for GPS or distance aids. They are independent of weather, and are exactly the same as the 150 yard marker. If you play by eye then why do you need the 150 marker?

It is good to know fairly accurately the distance to the pin as you can then make an educated adjustment on club selection based on how far you know you hit each club, be it in winter or summer. These devices give the correct yardage and will obviously help in this process. Do you not then look at the yardage on a par-3?

FixdePitchmark

Su,

Great stuff.

For me it is two clubs,

Can I add that lift is impacted on by density, so it would impact on ball too ?

But it is clear that drag is the key factor.

Su Campu

FixdePitchmark wrote: »

Su,

Great stuff.

For me it is two clubs,

Can I add that lift is impacted on by density, so it would impact on ball too ?

But it is clear that drag is the key factor.

Yes, lift is impacted by ball spin rate, whose effects are in return affected by air density. That is why dimple pattern design is so important.

This shows the effect on a shot in normal contitions (yellow), no air (blue) and in air but with no spin (pink). More here.

http://probablegolfinstruction.com/golf-ball-temperature.htm

The_Architect

Su Campu wrote: »

Again I'm not sure what you mean by there's no need for GPS or distance aids. They are independent of weather, and are exactly the same as the 150 yard marker. If you play by eye then why do you need the 150 marker?

It is good to know fairly accurately the distance to the pin as you can then make an educated adjustment on club selection based on how far you know you hit each club, be it in winter or summer. These devices give the correct yardage and will obviously help in this process. Do you not then look at the yardage on a par-3?

It is exactly because they are independent of weather that they lose their relevance. Variables in how far your ball will travel include temperature, humidity, wind, firmness, elevation change and quality of strike. The distance however, remains the same.

I throw the 150 yard marker out there as a bone to all those who need some safety blanket to hold on to. I'd prefer no distance aids. After all, we've only had them in Ireland for about 25 years.

I give a cursory glance to markers (and yardages on par-3's) because they are available and I can't help myself. But often I look at the shot as I approach, pick a club and hit.

Anyway, this point is somewhat off topic. I liked the science in your original post. I was just giving it a practical appliance.

Su Campu

The_Architect wrote: »

It is exactly because they are independent of weather that they lose their relevance. Variables in how far your ball will travel include temperature, humidity, wind, firmness, elevation change and quality of strike. The distance however, remains the same.

Of course, but distance is the MOST important thing to consider and the starting point for all the rest. Only after first knowing the distance can you then take into account all other factors.

Maybe for high handicappers the main goal is to just try to get off the tee and to get the ball up towards the green on every shot, but for the lower handicappers, who know pretty well how far they hit a club, these toolsl are important.

irish bloke

Su Campu wrote: »

Of course, but distance is the MOST important thing to consider and the starting point for all the rest.

Correct, as thats the one constant in all weather conditions.

Loire

Would it be an idea to "warm up" 18 golf balls the night before and wrap each in insulated foil and then change a ball on every hole?

BigCon

What about the effect of wearing less clothes in summer, this is also likely to give you a few extra yards as your swing will be "freerer"? Yes? No?

The_Architect

Su Campu wrote: »

Of course, but distance is the MOST important thing to consider and the starting point for all the rest. Only after first knowing the distance can you then take into account all other factors.

Maybe for high handicappers the main goal is to just try to get off the tee and to get the ball up towards the green on every shot, but for the lower handicappers, who know pretty well how far they hit a club, these toolsl are important.

My point being that with all of those variables, it is as easy to "feel" the shot for all but the elite. Distances can be very off putting exactly because of those variables. To think you need to know them to the nearest yard or two is nonsense.

Hence have a 150 yard marker for you to glance at. That's all 99.9% of us require.

Su Campu

BigCon wrote: »

What about the effect of wearing less clothes in summer, this is also likely to give you a few extra yards as your swing will be "freerer"? Yes? No?

Absolutely, and that's what I meant when I said about the effects on the player. I fine it annoying playing in rain gear and prefer to hop in and out from under the brolly to take shots rather than be lumped with a jacket.

Su Campu

Loire wrote: »

Would it be an idea to "warm up" 18 golf balls the night before and wrap each in insulated foil and then change a ball on every hole?

Yes, though I think there are rules against using things like handwarmers, etc.

dnjoyce

So the consensus on here seems to be that anyone who isn't a Cat 1 golfer has no need of a GPS/Laser as they don't consistently hit the ball a certain distance anyway, yet they should be heating their balls to a consistent temp the night before, allowing for the added rain weight on the club if wet and thinking about the density of the air to figure out their distances? Not doubting the science for a second, but it seems a bit OTT to me. There's enough swing thoughts to be thinking about already...

The_Architect

dnjoyce wrote: »

So the consensus on here seems to be that anyone who isn't a Cat 1 golfer has no need of a GPS/Laser as they don't consistently hit the ball a certain distance anyway, yet they should be heating their balls to a consistent temp the night before, allowing for the added rain weight on the club if wet and thinking about the density of the air to figure out their distances? Not doubting the science for a second, but it seems a bit OTT to me. There's enough swing thoughts to be thinking about already...

I think this is the heart of the matter.

Free your mind and hit the shot that feels right. Science and numbers (including exact distances) only serve to clutter it up and take away from the fun aspect of playing golf.

My opinion of course. I expect others to disagree.

L.O.F.T

The_Architect wrote: »

Free your mind and hit the shot that feels right. Science and numbers (including exact distances) only serve to clutter it up and take away from the fun aspect of playing golf

I totally agree with you. Just hit the shot you see. All too many times I play with lads that whip out the laser from 80 yards out and chunk it in front of them with a lob wedge or a lad who will laser a bunker 210 yards out from a tee box on a par four take a 3 wood to land shot of the trap and then proceed to slice the bejasus out of it 40 yards to the right and still 40 yards from the bunker. Just hit the ball, find it and hit it again. There are too many club golfers farting around imitating what they see on TV with neither the skill or sense to know better.

GreeBo

onedmc wrote: »

I think the science is a little sketchy.

Perhaps the drag due to air may increase by 10% but the significant force causing it to stop is gravity. Air making up say 10% so we have 10%of10%which in the example would be 1 meter.

Also not sure about an rh of 80% after a frosty night.

Friction is causing the ball to stop, not gravity. Gravity causes the ball to fall back to the ground, and it does this in the same way in winter and summer.

foxyboxer

IIRC Ben Hogan had 'hand' warmers in his pockets during the 1953 Open.

He also happened to use the hand warmers as a (pardon the pun) handy means of keeping his ball warm.

Not illegal back then but certainly is so nowadays.