Why can't the sun shine through the clouds?
534704
the condensation of water in the air as the air cools and consenses packs closely together and it does not allow the direct sunlight to shine through - however on days when it is overcast you are still likley to get burnt - \npeople tend to skip the sunblock when overcast because there is not direct san light/rays - but the sunlight and rays are still fintering thru - and you tend to get burn worse on overcast days then sunny ones!!!
889693
Because you only notice it when it rains on you.  You don't notice when the sun is out or it's just cloudy.
844556
Yes! Of course here in the UK it is not always 'blue' below the clouds! \n\nThe reason for the sky being blue is that as light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air. \n\nHowever, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky. Whichever direction you look, some of this scattered blue light reaches you. Since you see the blue light from everywhere overhead, the sky looks blue. \n\nTo get a fuller explanation (if you can bear it!) see the link below.\n\nGood question!\n\nx
836414
We can not control clouds but we can diver the direction of which it passes.  By using bombs and other chemicals it is possible.  It is used where agriculture lands are dried due to lack of rains.
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Clouds are tiny droplets of water that have condensed on condensation nuclei such as pollen, dust, ash, & pollution in the troposphere.\n\nB/c they are very tiny and independant of each other, they tend to be suspended. This is due to various things such as updrafts, winds, etc. They are very lightweight. Only when they begin to start growing in size will gravity take over & they start to fall as rain.
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You're obviously not looking hard enough!  After it's been raining (not this week) and the sun is coming out again, look at a cloud, a dark one is better than a light one, and you should be able to see how the edge of the cloud appears to be lined with silver
807689
They appear dark because they are very thick clouds and obscure sunlight from getting through. If viewed from above, they appear pure white.
580957
When the light from the sun hits the earth some of the light (The higher frequency or blue light) gets trapped or rather scattered by the smaller molecules in the atmosphere.  This scattering makes the sky blue because these particles reflect this blue light.\nAt night the light we are seeing is  the light of  the sun reflected off of the moon and it is much less intense.
1103987
Rainbows are caused by dispersion of sunlight as it is refracted by (approximately spherical) raindrops. The light is first refracted as it enters the surface of the raindrop, reflects off the back of the drop, and is again refracted as it leaves the drop. The overall effect is that the incoming light is reflected back over a wide range of angles, with the most intense light at an angle of about 40°–42°, regardless of the size of the drop. Since the water of the raindrops is dispersive, the amount that the sunlight is bent depends upon the wavelength (color) of the light's constituent parts. Blue light is refracted at a greater angle than red light, but because the area of the back of the droplet has a focal point inside the droplet, the spectra crosses itself, and thus the red light appears higher in the sky, and forms the outer color of the rainbow.\n\nA rainbow is an optical phenomenon whose apparent position depends on the observer's location. All raindrops refract and reflect the sunlight in the same way, but only the light from some raindrops reaches the observer's eye. These raindrops are perceived to constitute the rainbow by that observer. Its position is always in the opposite direction of the sun with respect to the observer, and the interior is actually a magnified image of the sun, which can be seen to be slightly brighter than the exterior. The bow is centred on the shadow of the observer's head, or more exactly at the antisolar point (which is below the horizon during the daytime), appearing at an angle of approximately 40°–42° to the line between the observer's head and its shadow (this means that if the sun is higher than 42° the rainbow is below the horizon and cannot be seen unless the observer is at the top of a mountain or a similar vantage point).\n\nSometimes, a second, dimmer rainbow is seen outside the primary bow, caused by a double reflection of the sunlight inside the raindrops, and appears at an angle of 50°–53°. Because of the extra reflection, the colours of the bow are inverted compared to the primary bow, with blue on the outside and red on the inside. (The full sequence of colors is red, orange, yellow, green, cyan, blue and violet.)\n\nA triple rainbow is even more rarely seen. A few observers have reported seeing quadruple rainbows in which a dim outermost arc had a rippling and pulsating appearance.
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wikipedia.com\n\n\nA cloud is a visible mass of condensed droplets or ice crystals suspended in the atmosphere above the surface of the Earth or another planetary body. The branch of meteorology that studies clouds is nephology.\n\nOn Earth, the condensing substance is water vapor, which forms small droplets of water (typically 0.01 mm of ice crystals) that, when surrounded with billions of other droplets or crystals, are visible as clouds. Clouds reflect all visible wavelengths of light equally and are usually white, but they can appear grey or even black if they are so thick or dense that sunlight cannot pass through.\nContents\n[hide]\n\n    * 1 Cloud formation and properties\n          o 1.1 "Hot Ice" and "Ice Memory" in cloud formation\n    * 2 Cloud classification\n          o 2.1 High clouds (Family A)\n          o 2.2 Middle clouds (Family B)\n          o 2.3 Low clouds (Family C)\n          o 2.4 Vertical clouds (Family D)\n          o 2.5 Other clouds\n          o 2.6 Cloud fields\n    * 3 Colors of clouds\n    * 4 Global dimming\n    * 5 Global brightening\n    * 6 Clouds on other planets\n    * 7 See also\n    * 8 External links\n\n[edit]\n\nCloud formation and properties\nA variety of cloud formations.\nEnlarge\nA variety of cloud formations.\nGlobal scheme of cloud optical thickness.\nEnlarge\nGlobal scheme of cloud optical thickness.\n\nClouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. This can happen in three ways.\n\n1. The air is cooled below its saturation point. This happens when the air comes in contact with a cold surface or a surface that is cooling by radiation, or the air is cooled by adiabatic expansion (rising). This can happen\n\n    * along warm and cold fronts (frontal lift),\n    * where air flows up the side of a mountain and cools as it rises higher into the atmosphere (orographic lift),\n    * by the convection caused by the warming of a surface by insolation (diurnal heating),\n    * when warm air blows over a colder surface such as a cool body of water.\n\n2. Clouds can be formed when two air masses below saturation point mix. Examples are breath on a cold day, aircraft contrails, and Arctic sea smoke.\n\n3. The air stays the same temperature but absorbs more water vapor into it until it reaches saturation.\n\nThe water in a typical cloud can have a mass of up to several million tonnes. However the volume of a cloud is correspondingly high, and the net density of the relatively warm air holding the droplets is low enough that air currents below and within the cloud are capable of keep it suspended. As well, conditions inside a cloud are not static: water droplets are constantly forming and re-evaporating. A typical cloud droplet has a radius on the order of 1 x 10-5 m and a terminal velocity of about 1-2 cm/s. This give these droplets plenty of time to re-evaporate as they fall into in the warmer air beneath the cloud.\nCumulonimbus cloud\nEnlarge\nCumulonimbus cloud\n\nMost water droplets are formed when water vapor condenses around a condensation nucleus, a tiny particle of smoke, dust, ash, or salt. In supersaturated conditions, water droplets may act as condensation nuclei.\n\nWater droplets large enough to fall to the ground are produced in two ways. The most important is through the Bergeron Process, theorized by Tor Bergeron, in which supercooled water droplets and ice crystals in a cloud interact to produce the rapid growth of ice crystals, which precipitate from the cloud and melt as they fall. This process typically takes place in clouds with tops cooler than -15°C. The second most important process is the collision and wake capture process, occurring in clouds with warmer tops, in which the collision of rising and falling water droplets produces larger and larger droplets, which are eventually heavy enough to overcome air currents in the cloud and the updraft beneath it and fall as rain. As a droplet f
1183383
The sky is beautiful, but clouds are just water vapors. How does a tree grow? Photosynthesis. Knowing how something occurs does make it less beautiful does it?
652845
Why are clouds white, you say? Clouds are white because the rain and sleet inside of the clouds scatters all sunlight equally creating white light. The same is true for White Cloud toilet tissue. White light bounces off of the fibers of the tissue, which scatters light equally and absorbs next to none.
500
A cloud compsition is primarlly just billions of drops of water or ice.  When such a cloud formation has an influx of water/ice, ie it's mass increases to include more water/ice, light finds it hard to pass through the mass, thus making it darker for us to see.\n\nIn a normal cloud, light can pass through the water/ice within the cloud and we see it as a distorted white/bluish/greyish/greenish hue.  But when the cloud is too thick with water/ice, the light doesn't pass through so easily and we see a darker spectrum.
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This question may be interpreted in two ways.  First, why is the sky not blue at night?  The answer for that is that the sky appears blue during the day because it scatters high energy sunlight.  The atmosphere scatters high energy starlight as well, but there isn't enough of that to make the sky appear blue.\n\nThe other interpretation is why is the sky not totally lit by stars?  That is actually a very important question that was pondered by famous astronomers.  It is called the Dark Night Sky Paradox, or Olbers' Paradox, and was contemplated by such notables as Halley and Kepler as well as the eponymous Heinrich Wilhelm Olbers.  If the universe is of infinite age (as was once assumed) and static, and the stars have had eternity to shine, shouldn't the sky be lit?  \n\nSome people hypothesized that the stars did not appear randomly in all directions.  (So the stars are arranged in straight lines with the Earth at the center so that starlight piles into intervening stars, and there are empty gaps?  Even before Hubble proved that "dark sky" is teeming with distant galaxies, that sounded stupid.)  Others said that dust in the way absorbed starlight.  But after an eternity of absorbing starlight, wouldn't the dust glow as well, and light up the night sky?\n\nThe fact that space is dark turns out to be proof in part that the Universe is not infinite, eternal, and static.  That in fact it had a beginning point in time and space and the Universe is changing.
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The sky is blue to us beause of Rayleigh scattering.  From outer space, you don't have that atmosphere effect, so it's black.
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Depends on atmospheric conditions ,small water droplets form into ice crystals in the upper atmosphere. The moon reflects light into these droplets causing refraction of that light, givind a halo effect sometimes even a 'luna rainbow'
50071
The whiteness of clouds is due to the tiny particles of water that make them up refracting the sunlight that enters them to make it appear brighter as it comes out. They are white because all wavelengths are allowed to pass through them; none are absorbed.\n\nThe fluffiness of some clouds is caused by the interactions of winds and pressures that force the water particles into a particular shape.