| Name |
Symbol |
Description |
| Cold front |
 |
Formed when a cold air mass replaces a warm air mass |
| Warm front |
 |
Formed when a warm air mass replaces a cold air mass |
| Stationary front |
 |
A slow-moving or stalled front between warm and cold air masses |
| Occluded front |
 |
Formed when a cold front overtakes a warm front |
| Surface trough |
 |
An elongated region of relatively low atmospheric pressure |
| Tropical wave |
 |
An atmospheric trough moving from east to west across the tropics |
| Squall line |
 |
A line of continuous or broken active thunderstorms |
| Dry line |
 |
A boundary separating moist and dry air masses |
