Cold Front-Cross Section
- warm air ahead of front is lifted up and over
- can get intense showers/thunderstorms at frontal boundary
- Cs and Ci clouds are blown ahead of the front by upper level winds
- cloud base is generally lower behind the front.... why???
- further behind the front, the air is quite dry, few clouds
- steep frontal boundary, slopes backward into the cold air
- frontal speed averages 15-25 knots
- temperature and wind profiles on either side of cold front???
- fronts can weaken with time - frontolysis
- fronts can strengthen with time - frontogenesis
- what processes can lead to frontogenesis? ANSWER
| from Meteorology Today by D. Ahrens | Before Passing | While Passing | After Passing | |||
|---|---|---|---|---|---|---|
| Winds | south-southwest | gusty; shifting | west-northwest | |||
| Temperature | warm | sudden drop | steadily dropping | |||
| Pressure | falling steadily | minimum, then sharp rise | rising steadily | |||
| Clouds | increasing: Ci, Cs and Cb | Cb | Cu | |||
| Precipitation | short period of showers | heavy rains, sometimes with hail, thunder and lightning | showers then clearing | |||
| Visibility | fair to poor in haze | poor, followed by improving | good, except in showers | |||
| Dew Point | high; remains steady | sharp drop | lowering |
