Green Conditions
Energy – Green snow is so cold, and therefore so tough, that it is mostly unresponsive to work or energy input. Grooming it and skiing on it doesn’t do much to break it down and dull the sharp edges of the ice crystals. In short, it doesn’t absorb energy.
Temperature – Generally, Green conditions are found in bitter cold. Snow near the legal racing limit of -20C (-4F) is almost always “green” snow. When conditions are particularly dry and when the snowpack is deep or dense, and well refrigerated by an extended period of cold weather, green conditions can persist in temperatures warming up into the single digits below zero C.
Snow Crystals – Green conditions can occur with just about any type of snow crystals. Very new crystals are more delicate than somewhat transformed crystals, and will reach a point where they are prone to transformation sooner (at lower temperatures) than more transformed snow, so new snow won’t persistently stay “green” at rising temperatures as long as older snow. Fully transformed crystals are generally more prone to releasing moisture, and so they also won’t persistently stay “green” at rising temperatures. The most persistently green snow is fine-grained, partially transformed, dense and sharp snow.
Moisture – By definition, green snow has essentially no free moisture.
Feeling – Green snow feels gritty or sandy, and has very high static frictional qualities.
Skis – Green conditions demand a “cool” and long pressure distribution to help deal with very high static friction
Grinds – Very fine and very smooth grinds are critical. In general, interrupted or crossing structures provide too much mechanical interface.
Waxing Considerations – Very hard surface treatments are necessary to combat the extremely aggressive crystals. Kick wax often involves binder because of the abrasive nature of the crystals. Kick is not hard to find, and is almost always drywax.
Geography – Green snow is most common a long way from the moderating influence of the ocean. The upper Midwest frequently experiences bitter cold conditions, particularly with the introduction of very strong continental polar high pressure which follows an Alberta Clipper storm system. Skiers in the upper Midwest should be sure to have dedicated green conditions skis and grinds. At the coasts, green conditions are much less common, and may not be a priority in fleet set-up.
Energy – Blue snow is typically newer snow which can absorb energy through the initial breakdown of a delicate crystal structure. This snowpack can absorb energy without releasing significant amounts of moisture.
Temperature – Blue conditions occur in moderate cold. They can run down deep into the negative teens Celsius when the snow is new, and was formed at moderate temperatures aloft.
Snow Crystals – The energy state of blue snow is caused by the capacity of the crystals to absorb energy as they break down and transform. Snow crystals that at a range of temperatures from about -3C down to about -12C are often stellar (star shaped) dendrites (branching structure). Stellar dendrites have intricate shapes and a lot of surface area, and are subject to quite a lot of transformation. These crystals are a good bet to provide blue conditions.
Moisture – Blue snow is typically dry, and can absorb moisture into its crystal structure. At the warm end of the range it may be possible to pack a light snowball with a little work. Any glaze in the classic track will break easily.
Feeling – Blue snow feels silky, and is considerably faster than green snow.
Skis – Blue conditions are tolerant of more focused pressure distribution than green conditions, but demand smooth transitions in the shape of the ski.
Grinds – Generally fine grinds built around managing a balance of static and kinetic friction, with shallow, low-angle release points provide good performance.
Waxing Considerations – “Blue” conditions – “Blue” wax. Easy.
Geography – Anyplace that boasts of its frequent “extra blue” skiing is trying to sell you blue conditions. In truth, this is a really nice range of conditions that is relatively common most places on a good snow year. Blue skis and grinds can be considered “universal cold” fleet elements for most of the country.
Temperature – Generally, Green conditions are found in bitter cold. Snow near the legal racing limit of -20C (-4F) is almost always “green” snow. When conditions are particularly dry and when the snowpack is deep or dense, and well refrigerated by an extended period of cold weather, green conditions can persist in temperatures warming up into the single digits below zero C.
Snow Crystals – Green conditions can occur with just about any type of snow crystals. Very new crystals are more delicate than somewhat transformed crystals, and will reach a point where they are prone to transformation sooner (at lower temperatures) than more transformed snow, so new snow won’t persistently stay “green” at rising temperatures as long as older snow. Fully transformed crystals are generally more prone to releasing moisture, and so they also won’t persistently stay “green” at rising temperatures. The most persistently green snow is fine-grained, partially transformed, dense and sharp snow.
Moisture – By definition, green snow has essentially no free moisture.
Feeling – Green snow feels gritty or sandy, and has very high static frictional qualities.
Skis – Green conditions demand a “cool” and long pressure distribution to help deal with very high static friction
Grinds – Very fine and very smooth grinds are critical. In general, interrupted or crossing structures provide too much mechanical interface.
Waxing Considerations – Very hard surface treatments are necessary to combat the extremely aggressive crystals. Kick wax often involves binder because of the abrasive nature of the crystals. Kick is not hard to find, and is almost always drywax.
Geography – Green snow is most common a long way from the moderating influence of the ocean. The upper Midwest frequently experiences bitter cold conditions, particularly with the introduction of very strong continental polar high pressure which follows an Alberta Clipper storm system. Skiers in the upper Midwest should be sure to have dedicated green conditions skis and grinds. At the coasts, green conditions are much less common, and may not be a priority in fleet set-up.
Blue Conditions
Energy – Blue snow is typically newer snow which can absorb energy through the initial breakdown of a delicate crystal structure. This snowpack can absorb energy without releasing significant amounts of moisture.
Temperature – Blue conditions occur in moderate cold. They can run down deep into the negative teens Celsius when the snow is new, and was formed at moderate temperatures aloft.
Snow Crystals – The energy state of blue snow is caused by the capacity of the crystals to absorb energy as they break down and transform. Snow crystals that at a range of temperatures from about -3C down to about -12C are often stellar (star shaped) dendrites (branching structure). Stellar dendrites have intricate shapes and a lot of surface area, and are subject to quite a lot of transformation. These crystals are a good bet to provide blue conditions.
Moisture – Blue snow is typically dry, and can absorb moisture into its crystal structure. At the warm end of the range it may be possible to pack a light snowball with a little work. Any glaze in the classic track will break easily.
Feeling – Blue snow feels silky, and is considerably faster than green snow.
Skis – Blue conditions are tolerant of more focused pressure distribution than green conditions, but demand smooth transitions in the shape of the ski.
Grinds – Generally fine grinds built around managing a balance of static and kinetic friction, with shallow, low-angle release points provide good performance.
Waxing Considerations – “Blue” conditions – “Blue” wax. Easy.
Geography – Anyplace that boasts of its frequent “extra blue” skiing is trying to sell you blue conditions. In truth, this is a really nice range of conditions that is relatively common most places on a good snow year. Blue skis and grinds can be considered “universal cold” fleet elements for most of the country.
Violet conditions
Energy – Violet snow is typically somewhat aggressive snow that cannot absorb high levels of energy into crystal transformation, and will release moisture with significant mechanical work, even at temperatures well below freezing.
Temperature – The moderate cold temperature range of violet conditions is much the same as for blue conditions. This can include very cold conditions, and certainly overlaps the green range on the temperature scale.
Snow Crystals – Violet crystals are duller and less complex than blue crystals. This can be due to duller crystals at formation, or a longer period of transformation including freeze-thaw and the recrystalization of an old snowpack at low humidities.
Moisture – Violet snow is usually dry because of the cold temperatures involved, but moisture is released through work and will form a freezing glaze at the surface relatively quickly.
Feeling – Violet snow is usually extremely fast, even when it feels harsh, abrasive and rough.
Skis – Violet conditions are almost always fast, and ski selection is focused around stability, control and wax pocket cushioning. Typically violet conditions require stiffer skis. In some cases skis with a very hot pressure distribution can be extremely fast.
Grinds – Violet conditions are a good bet to favor heavier structures than the other cold conditions. It is not a surprise to find a wet ski and grind running well in these conditions.
Waxing Considerations – Generally harder & highly fluorinated glide waxes. Kick wax will be a binder or klister cushion under hardwax, or straight cold klister.
Geography – Areas with less than consistent snowfall and temperatures frequently crossing the freezing line are good bets for violet conditions. Manmade snow usually starts off in the violet range. New England and Central Europe are good bets for a good shot of violet conditions in any given season.
Temperature – The moderate cold temperature range of violet conditions is much the same as for blue conditions. This can include very cold conditions, and certainly overlaps the green range on the temperature scale.
Snow Crystals – Violet crystals are duller and less complex than blue crystals. This can be due to duller crystals at formation, or a longer period of transformation including freeze-thaw and the recrystalization of an old snowpack at low humidities.
Moisture – Violet snow is usually dry because of the cold temperatures involved, but moisture is released through work and will form a freezing glaze at the surface relatively quickly.
Feeling – Violet snow is usually extremely fast, even when it feels harsh, abrasive and rough.
Skis – Violet conditions are almost always fast, and ski selection is focused around stability, control and wax pocket cushioning. Typically violet conditions require stiffer skis. In some cases skis with a very hot pressure distribution can be extremely fast.
Grinds – Violet conditions are a good bet to favor heavier structures than the other cold conditions. It is not a surprise to find a wet ski and grind running well in these conditions.
Waxing Considerations – Generally harder & highly fluorinated glide waxes. Kick wax will be a binder or klister cushion under hardwax, or straight cold klister.
Geography – Areas with less than consistent snowfall and temperatures frequently crossing the freezing line are good bets for violet conditions. Manmade snow usually starts off in the violet range. New England and Central Europe are good bets for a good shot of violet conditions in any given season.
Red Conditions
Energy – Red snow responds to energy input or mechanical work by releasing moisture.
Temperature – Moderate, plus/minus zero Celsius temperatures are a good bet to produce red conditions.
Snow Crystals – Red conditions can develop with a wide range of crystal types, but typically involve some finer snow in at least a mixed conglomerate. Snow that is fully transformed and coarse will often go straight from violet conditions to yellow conditions with rising temperatures. Red snow is really good snowball snow.
Moisture – Red snow does not need to start wet, but it is high in moisture and will produce a surface glaze quickly.
Feeling – A high level of available moisture provides constant and ready lubrication at the surface. Red snow is slippery.
Skis – Skis for red conditions want a more focused, “hotter” pressure distribution than blue or green skis, but smoother transitions than yellow skis.
Grinds – Interrupted crossing structures with decent depth and a high density of release points are a good bet. The wide range of crystal types involved with red conditions means that a wide range of specific structures may be applicable.
Waxing Considerations – Like grinds, a wide range of crystal structures means a wide range of waxes. Kick wax can be either warmer hardwax or thin klister. Red conditions are the “cold” end of the hairies or zero ski range.
Geography – Every part of the continent experiences red conditions. Often they come in transition from blue or violet as the day warms and the solar effect comes into play. Red conditions are more prevalent in February and March than in December and January because of the increased solar effect as the season progresses. Red conditions may be really central for an area like the Pacific Northwest. For the rest of the country red skis and grinds can be considered “universal warm”.
Temperature – Moderate, plus/minus zero Celsius temperatures are a good bet to produce red conditions.
Snow Crystals – Red conditions can develop with a wide range of crystal types, but typically involve some finer snow in at least a mixed conglomerate. Snow that is fully transformed and coarse will often go straight from violet conditions to yellow conditions with rising temperatures. Red snow is really good snowball snow.
Moisture – Red snow does not need to start wet, but it is high in moisture and will produce a surface glaze quickly.
Feeling – A high level of available moisture provides constant and ready lubrication at the surface. Red snow is slippery.
Skis – Skis for red conditions want a more focused, “hotter” pressure distribution than blue or green skis, but smoother transitions than yellow skis.
Grinds – Interrupted crossing structures with decent depth and a high density of release points are a good bet. The wide range of crystal types involved with red conditions means that a wide range of specific structures may be applicable.
Waxing Considerations – Like grinds, a wide range of crystal structures means a wide range of waxes. Kick wax can be either warmer hardwax or thin klister. Red conditions are the “cold” end of the hairies or zero ski range.
Geography – Every part of the continent experiences red conditions. Often they come in transition from blue or violet as the day warms and the solar effect comes into play. Red conditions are more prevalent in February and March than in December and January because of the increased solar effect as the season progresses. Red conditions may be really central for an area like the Pacific Northwest. For the rest of the country red skis and grinds can be considered “universal warm”.
Yellow Conditions
Energy – Yellow snow starts fully saturated, and energy input or mechanical work will generally cause it to break down and soften.
Temperature – Warm, above freezing conditions.
Snow Crystals – Yellow conditions can occur with any type of crystals. Typically new snow will melt and transform quickly at these temperatures, and starts out very wet. New snow yellow conditions may be some of the most difficult and frustrating, not to mention slow, of the entire range of skiable snow conditions.
Moisture – Wet – copious amounts of free moisture.
Feeling – The dominant feeling of yellow snow is “sucky”, in greater or lesser degrees.
Skis – The specifics of bridge action and pocket shape are brand-specific, but pressure distribution and glide surface shape must be focused on limiting surface area contact with the snow.
Grinds – Sharp, aggressive, and hopefully dirt resistant.
Waxing Considerations – Soft waxes, sticky kick waxes and hairies.
Geography – The colder parts of the country may not see yellow snow until the Spring. In the Northwest and the Northeast it’s a good bet that there will be some yellow days during the mid-season. Anybody who plans to race into March ought to have some yellow skis and grinds in the bag.
Temperature – Warm, above freezing conditions.
Snow Crystals – Yellow conditions can occur with any type of crystals. Typically new snow will melt and transform quickly at these temperatures, and starts out very wet. New snow yellow conditions may be some of the most difficult and frustrating, not to mention slow, of the entire range of skiable snow conditions.
Moisture – Wet – copious amounts of free moisture.
Feeling – The dominant feeling of yellow snow is “sucky”, in greater or lesser degrees.
Skis – The specifics of bridge action and pocket shape are brand-specific, but pressure distribution and glide surface shape must be focused on limiting surface area contact with the snow.
Grinds – Sharp, aggressive, and hopefully dirt resistant.
Waxing Considerations – Soft waxes, sticky kick waxes and hairies.
Geography – The colder parts of the country may not see yellow snow until the Spring. In the Northwest and the Northeast it’s a good bet that there will be some yellow days during the mid-season. Anybody who plans to race into March ought to have some yellow skis and grinds in the bag.
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