explanation:
high and low pressure systems produce opposing weather conditions. high pressure systems are generally associated with fair weather, while low pressure systems bring clouds, precipitation and sometimes stormy conditions.
fair vs. stormy conditions
high and low pressure systems produce opposing weather conditions. high pressure systems are generally associated with fair weather, while low pressure systems bring clouds, precipitation and sometimes stormy conditions. while just sunshine and fair-weather clouds typically accompany high pressure systems, a range of conditions, ranging from mild drizzle to heavy snow to intense lightening, occur under areas of low pressure. additionally, high pressure systems usually produce only light winds, while the storminess associated with low pressure systems can produce strong, sometimes even damaging winds.
sinking vs. rising air
high pressure systems entail sinking air, while lows entail rising air. high pressure systems form where air converges in the higher levels of the atmosphere. the converging air has nowhere to go and is forced to sink toward the ground. this sinking effect inhibits cloud formation and therefore precipitation. in contrast, low pressure systems form where air near the ground converges. with no place else to go, it rises. in doing so, water vapor cools and condenses into tiny water droplets or ice crystals, producing clouds and precipitation.
clockwise vs. counterclockwise wind flow
due to the rotation of the earth -- precisely, the coriolis effect -- winds spiral around high and low pressure systems in a circular pattern. but they do so in opposite directions, and these directions are reversed in the earth’s two hemispheres. in high pressure systems, the air flows clockwise in the northern hemisphere and counterclockwise in the southern hemisphere. with low pressure systems, winds blow counterclockwise in the northern hemisphere and clockwise in the southern hemisphere.
