Synoptic Charts Flashcards
Isobars
Joins places of equal air pressure, closer isobar means windier weather.
High pressure system
Anti-cyclone, air is moving towards the surface, air rotates in anti-clockwise directions (H).
Low pressure system
Cyclone, air rotates in a clockwise direction (L).
Wind direction/speed
Arrow that shows the direction of the wind and speed, measured in knots, tail end = direction of the wind.
Low air pressure
Less air (air moves away from the Earth’s surface/up as it condenses, higher altitudes have lower air pressure due to less air above.
Generally overcast/cloud weather, rainfall, and strong winds.
High air pressure
More air (air is moving towards the Earth’s surface, lower altitudes have a higher air pressure as more air above).
Generally stable conditions and clear skies.
Cold front
Line of cool air moving, cold air is denser so it wedges under warm air when moving (causes warm to to rise, making rain droplets).
Indicates change in temperature or wind direction.
Spikes, sometimes blue
Warm front
Line of warm air moving, can mean humid conditions.
Bumps, sometimes red.
Trough
Large area of low pressure, separates moist from dry air (line of sometimes blue dashes).
