Wider tires tend to float on the snow. Narrower tires tend to press down and compact the snow, and tend to have better traction and stopping ability because they are operating on a denser surface.
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It appears that Jim has his facts wrong and Shanonia also thinks the narrow snow tire is better .
All tires have a flotation rate, which is a bit confusing now that people talk about “flotation tires” that are used in some agricultural, OTR (Like earthmover) and roles when you want the tire to “float” over terrain without digging into soft soil or over grass with a lawn tractor without disturbing to turf. What I am talk about is the difference between 205/60/R16 instead of 205/55/R16. In a situation where you are not going to hit dry pavement the 60 series tire will give you slightly more flotation out of the 60 series tire, and this will impede the problem of the spinning tire digging in getting stuck by just a bit. (The 60 series tire has a bit more flotation than the 55 series tire.) I definitely would not go to a narrower tire than a 205/60/16R. If you live in a city and a locale that has good snow clearance or road treatment, it’s six of one and half a dozen of the other. When I lived in Chicago I had 235s on my truck rather than 265s. Now I am rural and the 265s make more sense. Talking about my current vehicles, I went from the 235/70/r15 to the 265/75/r15 (actually 31/10.5/R15) because the latter is not a small size for a truck (and is soon to be the smallest/only size available on a 15 inch wheel, I do need a Hwy/AT tire and I do know the higher (though small) flotation of the 75 series over 75 does help in mud, snow, situations as well as works better on the rocky, unimproved roads I frequently drive on. (Ditto with wife’s SUV going from 70 series to 75.) I stand behind my “facts” that going up one level (205 to 215 or 55 to 60) is inconsequential on most cars. If you are concerned that I have lost complete control of whatever remaining mental acumen I have left in my retirement years, let me assure you that I still have friends and family who are tire engineers in the same big five tire company I worked for who still concur with me.
Sorry, should have read 235/70/r15 to 265/75/r15. It is becoming hard to find a premium 235 tire for a 15-inch wheel, and I actually have LT 31x10.5r15, but even that is becoming less common. As I stated elsewhere, all tires have float. Wide, low aspect tires have less float than small or medium tires with high aspect ratios do (think of the 83 aspect wide-whitewall tires you grandfather’s Studebaker came with). It is not a theory (at least it is not mine). Very seldom can you design a tire for optimal conditions, since conditions are always changing for road tires. In real life conditions different flotation rates work better in some conditions than others. I hope you understand that there are other design features 0f a tire that affect the handling, mileage, safety, braking, and ride if a tire much more than flotation rate.
Everyone has to be careful here. Tire traction in snow is complex, mostly because if even a tiny bit of the tire can get to the road surface, that has better traction.
And when there is no contact with the road surface, then there is the issue of how much of the tread pattern is in contact with the snow - and a lot of that is dependent on inflation pressure. Comparing 235/70R15’s to 265/75R15’s is problematic because of the inflation situation.
And that is also the same for 31X10.50R15LT’s, which is a different animal than a 265/75R15 and presents its own issues when trying to do a comparison.
The problem here has much to do with the material science of snow (which continues to change). I have tried not to get too technical, and let’s see if I can continue. Snow is much more complex than it seems. Most of us notice changes that occur with snow over time, but the changes are more numerous and come more quickly than most can observe. When snow falls it does so as hexagonal crystals, from nearly perfect snowflakes to single hexagonal rods. These initially are more or less dropped as an aggregate with a higher coefficient of friction than what it soon becomes (it is less slippery than ice). However, this aggregate soon fuses into a substrate with “sharp edges”. As time goes on, the substrate becomes more fused and rounded, with melt water from radiant or environmental heating refreezing and becoming part of a crystalline lattice of hard ice. (If you live where it is -22 degrees F, you can skip all that–it is just too cold for snow to change all that much. But then you have other problems.) On the fresh snow, more flotation helps the tire to roll over the aggregate of ice crystals. If this is just a little skiff of snow the lower flotation tire will have an edge. Past that it gets complicated. Any Passenger tire will exert enough pressure to compress snow–to a point. Compression of snow is a vexed thing. Compression adds heat and pressure and effectively lowers the melting point of snow. So, the result is (unless in light snow) hard, glazed, road ice. The debate is whether it is better to have a smaller patch on the ice with higher pressure, or whether you can more safely transverse the high with a bit more flotation. I like the larger footprint. I suspect that other factors, like driving skill, whether you use traction control, limited slip differential, and antilock brakes make this small difference. (For the record, I don’t use traction control, I can drive better than it does.) Please remember we were talking about the difference between a 60 series and a 55 series tire. I have tried to come up with an analogy by what I mean by flotation as it relates to passenger tires. This one is flawed, but let’s see if it helps. In some ways a tire is like a basketball. The ball bounces like a spring, because it conserves the kinetic energy of the drop by compressing and expanding molecules to bounce. (BTW, in my younger days I could dribble mounted and fully inflated tires.) The ball has to be at an optimal pressure. A higher flotation passenger tire has an optimal pressure that allows the tire to compress and expand. What this means for us who with imperfect road surfaces (including snow and icy roads) the tire can flex and maintain better contact with the road. That’s the simplest (and unheated) way I can think to explain it. Believe me, don’t believe me, that’s fine with me. But please don’t tell me my facts are wrong. I’ve had years with resources one could only dream of.
Thanks you for your comments. There is really no difference between an LT 235/75r15 and an LT 31x10.5r15. Both are expressions of size (not construction) and they are the same size. The tires I used to replace the 235/70r15s are much different, true, but they were not LT tires. My point was that it was an easy switch, and had better flotation than the LT 2235/70r15s (which I could not even buy at that point). I do not inflate my tires past the limit of a similar sized passenger tire because I rarely heavy loads in my personal truck (although I would if I did). I don’t see the complication here. I agree snow is complex as a material. Even the commonly accepted theory self lubrication from compression melting of water (What makes ice slippery?) is under much scrutiny now. The latest theory I remember was that ice as a material was sheds microscopic ice balls that act as ball bearings on an agitated surface. I frequently hear misinformation on tires (even from so-called experts) and I usually just bite my tongue. But every once in a while my OCD sort of takes over. I apologize for that.
I can’t seem to wade through that wall of text that Jim posts .
All I know is that the majority opinion from tire manufactures and road test articles point to narrow tires being better in snow than wide ones.
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Please point me to your data. I am not trying to be impertinent, but all I know could possibly be more than all you know. I wonder from other comments that you have made if you have ever even worked in the industry or follow the technology that closely. I gave friendly and trustworthy advice and you told me I was all wrong without any reasoned rebuttal. And we are talking about two tires that have a difference in diameter of 0.8" and no difference in width. There is a slight difference in flotation they may not be noticeable, but I believe if is could actually be helpful. That is what you are fussing at me about. And you may be surprised that winter tires were originally designed with front wheel drive vehicles in mind. Any place winter tires are appropriate for RWD cars they are also appropriate for FWD. I have lived in Akron, Chicago, and Michigan, and if I had a FWD vehicle there, I would use winter tires. Bottom line–the answer to the OP is “Sure, go ahead and buy the 205/60-15s.” My friend, you are speaking beyond your experience and knowledge at my expense. I am asking please just to stop.
You do know you’re contradicting a tire expert/professional, right?
Apparently, I did not, but the difference in measurement is minimal. No, I do not know what your professional expertise is, but the same carcass can (and in some cases has) gone into each. I used to be in a part of the world where LT 235/75r15 was the preferred designation, while the American version was LT 235/75r15. In that case, there really was no functional difference. Each had the same load rating, the same number of ply’s, the same compounding, etc. I assume that you have in mind a 235/75r15 with essentially a passenger car construction in a tire mold, and a 31x10.5r15 with higher inflation capability, load ratings etc. I slipped back into the metric sizing out of old habit. I don’t see the contradiction, though, as these are fundamentally differences in expressing a size in metric vs. English. I had no intention to offend. I purposely in being vague because I do not wish to identify which builder I worked for. I don’t really care for comments people make comparing one with the other, and I have gotten used to a "don’t ask, don’t tell’ way of life. I used to live in Akron. I worked in one of companies there (before they got bought by others). I worked in the shadow of my father who was simultaneously Chief Engineer of Passenger Car Tires and the director of the company’s research and technology lab. At some point I decided I really wanted a Ph.D. and became a professor rather then returning to the company, but I have kept close with some of my connections since then. Unfortunately, father was selected to be the incoming VP of research and technology but suffered a heart attack in the company jet which led to his demise. Besides my work experience, I tried to glean everything I could from my father even until his death. I still read technology journals, talk with engineers, etc. So I do not know how that rates with you, but I have lived, studied, worked tires all my life. And I would love to chat with someone who really knows tires. So are we square on the size thing? I hate having to edit my posts for typos.
Allow me to clear the air:
A 31X10.5.R15LT Load Range C is supposed to be 30.5" in diameter, 10.5" wide on an 8.50" rim with a load carrying capacity of 2270# at 50 psi
An LT235/75R15 Load Range C is supposed to be 28.9" in diameter, 9,25" wide on a 6.50 rim
with a load carrying capacity of 1985# at 50 psi(single).
So, No!! They are not even close. They are different.
I could go on, but I am going to stop there. Just allow me to make a quote: “…My friend, you are speaking beyond your experience and knowledge … I am asking please just to stop.”
Yes, please stop.
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And you’re the one that came here asking if a 20 year old tire was safe.
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I think JimLowther and TheWonderful90’s should have their own private space where they could see who can out BS the other.
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Wouldn’t it be better to debate the contributor’s content, rather than attacking the person?
I think JimLowther and TheWonderful90’s should have their own private space where they could see who can out BS the other.
As long it is on the down hill side from the rest of us. 
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maybe they are the same person. like he was Snowman first.
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Let these 2 go at it in private so they quit annoying the rest of us. Who exactly did I attack? Suggesting they go private is an attack now?
Yep! That’s me! I knew someone would pick that up. I am very OCD. I had already decided to let it go, but it is an OCD thing to double check because the tire looked so pristine. I also called an old friend who worked at the company, as well. It’s gotten worse in my old age. Thanks for your concern.