Weather

• Weather elements


  • Temperature
  • Air pressure
  • Humidity
  • Wind
  • Clouds

  
• Temperature


  Hotness or coldness, or the amount of heat stored in an object
• Thermometer


  • Used to measure temperature in degrees Fahrenheit or Celsius
  • Most temperature measurements are expressed in degrees Celsius (°C)
  • Must be shaded from sunlight and subjected to proper ventilation to match the ambient air temperature

  
• Air particle movement


  The higher the temperature, the faster the air particles travel
• Temperature and elevation


  Air temperature is cooler at higher elevations above ground
• Air pressure


  The level of force applied by the air in a given air mass
• Barometer


  • Used to measure air pressure

  
• Altitude and air pressure

  The higher you are, the less air is pressing on you, and hence the pressure is lower
• High-pressure and low-pressure areas

  High-pressure conditions are warmer and drier, while low-pressure conditions are cooler and cloudier
• Humidity


  The amount of water vapor in the atmosphere

  
• Absolute humidity


  The amount of vapor present within a packet of air or the pressure exerted by the water vapor

  
• Relative humidity


  Obtained by comparing the actual mass of vapor in the air to the mass of vapor in saturated air at the same temperature

  
• Dew point


  The temperature at which condensation forms

  
• Hygrometer


  An instrument used to calculate different humidity measures

  
• Wind


  Air in motion, created by changes in pressure or temperature between two points on the Earth's surface
• Wind


  • Defined by speed and direction
  • Direction is expressed by the compass point from which the wind is blowing
• Anemometer


  An instrument used to measure wind speed
• Clouds


  Noticeable arrays of water droplets and/or ice crystals held in the atmosphere
• Clouds


  • Classified into four major classes: cumulus, stratus, cirrus, and nimbus
  • Further categorized by cloud base height: high-level (cirr-), middle-level (alto-), and low-level
• Cloud types


  • Cumulus
  • Stratus
  • Cirrus
  • Nimbus
• PAGASA cloud description


  • Sky condition definitions

  
• Cirrus clouds


  The highest of all clouds
• Cirrus clouds


  • Cirrus clouds, El Calafate, Argentina
• Nimbus clouds


  Can be beautiful but often bring with them heavy rain and lightning

  
• Nimbus clouds


  • Nimbus clouds
• Cloud names with prefix 'cirr-'


  Found at high levels
• Cloud names with prefix 'alto-'

  Found at middle levels
• Cloud Classification

  • High level clouds
  • Middle level clouds
  • Low level clouds
• PAGASA Cloud Description


  • Sunny
  • Partly cloudy
  • Cloudy
  • Rainy
  • Stormy

  
• Air pressure


  Air blows from high atmospheric pressure regions to low atmospheric pressure regions
• High-pressure environment


  Air pressure is greater than in the surrounding areas
• Winds


  Blow into low-pressure areas when air travels from higher pressure areas to lower pressure areas
• Winds blowing into low-pressure areas

  Uplift the air, resulting in the formation of a depression with clouds and rain
• Air increases

  It expands, resulting in cooling and a drop in temperature
• Temperature drops


  Humidity in the air increases until it reaches 100%
• Air becomes saturated

  Water vapor begins to condense as tiny water droplets, resulting in the formation of a cloud
• Warm air


  Capable of holding more vapor than cold air
• Weather forecasts are scientific predictions of future weather patterns

  
• Weather data obtained during observations is analyzed before a forecast is generated and released to weather stations throughout the country

  
• By making observations in different ways, there are endless questions to be answered, numerous discoveries to be made, and limitless knowledge to be known