why does snow fall in invidual flakes? why isnt it just a single falling sheet?
156358
Snow is frozen/crystalized rain.  When the rain drop leaves the cloud, it will freeze as it descends to earth.  This frozen rain drop is what we call snow.
14429
Of course snow and ice are both composed of H2O, water.  They are two frozen forms of water that depend on different crystaline structures.  Snow flakes consist of six-sided symmetrical crystals (no two alike) that grow dendritically (like the branches of a pine tree).  Ice is formed when heat is removed from water (as in a refrigerator) slowing down the vibrations of the water molecules until they can join and bond together in solid chains that use space less efficently than liquid water.  Therefore the ice is less densly packed than water and floats.  We know that 90% of an iceberg is floating under water and 10% above because ice takes up more room than the water that formed it.
411859
Its rare, but it can lightening when it snows
13870
Snow is made of small crystals of ice that have a different refractive index due to the air between them. When light passes across an interface between\ntwo media with different refractive indices, some of it reflect off the interface, and some is transmitted at an angle.  Every transit causes a\nscattering of the light, so that eventually light falling the sample is returned in every direction. When all the light is reflected naturally it will be white. \nIce on the other hand lets the light through making it colorless - it is a single crystal!
552581
Snow is water molecules clinging to each other in the atmosphere, then falling to earth. Frost is water molecules freezing (thus clinging) to a foriegn solid mater.
492491
Water vapor is transparent (for most purposes) and so mere humidity in the atmosphere can't be a cloud. Since clouds don't have motors keeping them in the air, and yet stay there for hours in some cases, they can't be solid, for if they were, they'd fall out of the sky and we'd find cloud bits laying around on the ground. And the same is true for liquid as well. \n\nSo what's a cloud? Mostly, it's very small bits, so small that air currents can keep them in the air. The bits can be solid (eg, ice crystals of which snowflakes are examples), or liquid (eg, little drops of water, of which rain is an example). In either case, enough of these small things begin to look white as light passes thorough them and is reflected and refracted and generally diverted. Kind of like the effect of fine particulate suspensions in water. They are sometimes referred to as milky looking. Indeed, milk is white for a similar reason.\n\nThese are usually formed around dust bits, for real. High humidity (forced by cooling temperatures) produces supercooling (ie, ready to condense, if a trigger can be found). The dust motes provides the trigger. With updraft winds, a condensed drop can grow pretty large. And if it goes high enough, and gets cold enough, the drop can freeze (and thus make hail). If the orignal condensation is sufficiently cold, then water will be added to an ice crystal. With the proper history, such crystals become snowflakes.
770917
They are different because there is no reason for them to be identical.  That sounds overly simple, but that is the idea.  There is only one way to be identical, so there are billions or trillions way for them to be different, so what are the odds that two would be equal?  Very low, so low it is virtually zero.\nAs for the symmetry, the condition that makes the flakes grow is that additional molecules of water add to the existing crystal as a function of what conditions exist; and since flakes are small, the conditions are nearly identical around the flake, hence it will tend to grow symmetrically.  But what about a snow flake right besides the first one?  Shouldn't it be growing similarly to its neighbor and thus be identical? Yes, provide that the starting crystal formed at the same moment, and with the same angle (as snow flakes are flat, that means the way they will grow depend on their angle as a function of time). Again the chance two flakes will start growing at the same time, and are at the same angle is essentially non-existent.
95097
If you look at an individual snowflake you will find that the frozen water it contains is quite clear. It is only snow in drifts that looks white. Why? Because snow in drifts is  made up of millions of tiny pieces of ice.\n\n\nEvery time light passes from one substance to another rit changes direction. So when you see something underwater it looks like it’s in a different place to where it is because the light has changed direction moving from the water to the air.\n\nWhen light changes direction like that it also gets split up into different colours  a bit, just like if it had passed through a prism.  It isn’t split as completely as if it has passed through a prism, but the blue light gets split out just a bit more than the red. And every time it changes direction it gets split more and more.\n\n\nWhen light passes through a snow drift it will change direction every single time it shines into every individual snowflake. So light shining on a snowdrift changes direction millions of times. And every time it changes direction it gets split up a bit more. By the time it has shone right through the drift it has changed direction so many times that it has completely split into all the separate colours.\n\nWhen your eyes see an object that is producing light in al the different colours at once it registers that as white. And because the light shining through a snowdrift been split into all the different colours the snow becomes white.\n\nIce on a stream or lake on the other hand is a single block, not millions of pieces like a snowdrift. When light shines through a block of ice it changes direction just twice: once when it enters the ice and once when it leaves it. It doesn’t change direction often enough to get split up very much, so the light coming though looks normal, and not white. The ice appears clear.
857205
Lightning does occur during snowstorms, it is just much rarer.\n(I have personally witnessed it.)\nI believe it does not occur as much, as the theory of lightning is that it builds up electricity from friction at the molecular level. However, in the extreme cold of a snowstorm, it would take a much greater amount of friction to generate enough electricity for lightning to form.
28574
Lightning can happen when it snows.  The reason lighting happens is because the air in the clouds is negatively charged compared to the ground (making the clouds (-) and the gorund (+)).  The clouds usally get this way in dry conditions cause there is less moisture in the air to stop air molecules from rubbing up against one another and creating excess energy (a negative charge).  Well since the clouds are (-) it needs a way of getting rid of some energy so it can be neutral (n).  It does this by passing some energy in to the (+)  ground, which also want to be (n).  This passing of energy rips throught the (n) air in between the (-) clouds and the(+) ground and creats the effect of lightning.  Now the reason it usually doesn't happen when it snow is because of the moisture in the air being so high, but everyonce in a while the air become dry enough when it snow to produce lightning.
19113
It has to do with the 120-degree H20 water molecules (oxygen in the center, one hydrogen on each end) and how they crystalize as they freeze.  Snowflakes always form into 6-pointed stars.
833095
an updraft of cold air freezes water droplets into crystle. All of them are 6 sided, and EVERY ONE of them is different - amazing eh.\n\nyou can go to http://snowflakebentley.com/snowflakes.htm for cool pics and \nhttp://www.kidzworld.com/site/p1587.htm\nto see how snow is formed.
174629
Snow grains are tiny circular bits of snow - i.e., no bigger than a grain of sand (hence the name). What you are probably referring to are snow pellets - larger hard balls of snow. You are not seeing those if you think they might be hail. There are also ice pellets - small balls of ice (frozen raindrops).\n\nWe like to classify things, but sometimes it is ambiguous. E.g., if a snowflake collides with a raindrop and freezes, it may look very much like an ice pellet but with a little white frozen spot inside. That would not be hail, because hail as mentioned requires  the formation of layers from vertical motions in the clouds. You may be seeing hail, but at this time of year I think it more likely is some sort of mixture between and ice and snow pellets.
85299
When it is very cold clouds do freeze. In fact even on a hot summer’s day the high clouds are normally frozen. \n\nThe reason they don’t; fall down is because ice isn’t any heavier than liquid water. When you freeze the droplets that make up a cloud they don’t gain any weight, they just turn from a liquid to a solid. You can prove this your self by  filling an ice cube tray with water and weighing it. After you freeze it solid you can weigh it again and the weight will be EXACTLY THE SAME.\n\nBecause frozen clouds made of ice are no heavier than clouds made of liquid water there is no reason why they should fall down. \n\nClouds are made of billions of tiny droplets of water. You can see this for yourself if you go outside on a foggy night with a flashlight. Fog is nothing but a cloud that has formed very close to the ground, and the flashlight beam will show that the fog cloud is made up of lots of little drops of water floating in the breeze. \n\nA cloud is kept in the sky because the wind is constantly blowing those tinny water drops upwards and preventing them from falling. When those droplets freeze they are still blown around in the wind like tiny little snowflakes (but they are not snowflakes).
1032082
Well, snow is frozen water, like ice cubes, which are sometimes white depending on how they freeze.\n\nWhat you see is white are actually snowflakes or snow crystals all piled up together.  They're white because of the way the sun reflects off of them.\n\nWhen they melt they return to water, which doesn't reflect the sun the same way, so you don't see any more white.
214123
they say no two snowflakes are alike, but they are usually hexagonal in shape, although some can be three sided, 12 sided, or just plain irregular\n\nfor more info into how many shapes check:
242077
The snow holds pockets of air which act as insulation.Because they are low and round the heat circulates lower in the shelter.The heat is provided by the human body and can be regulated by the individual possessing that body.The igloo also shelters from the elements such as wind chill