Fronts
A warm front marks the leading edge of warm air advancing over cold air. It brings a gradual deterioration: high cirrus cloud, then lower cloud, steady rain, poor visibility, and a rise in temperature as the front passes. Wind typically veers at the front.
A cold front marks cold air undercutting warm air. It passes more quickly with heavier rain, squally winds, and a sharp drop in temperature. Visibility improves dramatically after a cold front passes. An occluded front combines features of both.
Key Points
- Warm front: gradual deterioration, steady rain, poor vis, temp rises, wind veers
- Cold front: sharper change, heavy rain, squally, temp drops, vis improves after
- Occluded front: combined features of warm and cold fronts
- Warm sector: between warm and cold fronts, often overcast with drizzle