Table of Contents
- 1 What happens when a cold front is coming?
- 2 What often happens after a cold front passes?
- 3 What weather comes before a cold front?
- 4 How does a cold front occlusion develop?
- 5 What weather happens before a cold front?
- 6 Why does it rain before a cold front?
- 7 How are cold fronts different from warm fronts?
- 8 How are cold fronts represented on weather maps?
What happens when a cold front is coming?
If a cold front is approaching, precipitation is possible just before and while the front passes. Behind the front, expect clearing skies, cooler temperatures, and lower relative humdities. The air cools as it rises and the moisture condenses to produce clouds and precipitation ahead of and along the cold front.
What happens when a cold front passes wind?
As the cold front passes, winds become gusty. There is a sudden drop in temperature, and also heavy rain, sometimes with hail, thunder, and lightning. Atmospheric pressure changes from falling to rising at the front.
What often happens after a cold front passes?
After the cold front passes a point, winds turn to the west, northwest, or north. Since the cold air is very dense it is very effective at displacing the warm air ahead of it. The dense cold runs under the warm air lifting it.
What happens when warm front passes?
When a warm front passes through, the air becomes noticeably warmer and more humid than it was before. An abrupt temperature change over a short distance is a good indication that a front is located somewhere in between. If warmer air is replacing colder air, then the front should be analyzed as a warm front.
What weather comes before a cold front?
| Before Passing | After Passing | |
|---|---|---|
| Temperature | warm | steadily dropping |
| Pressure | falling steadily | rising steadily |
| Clouds | increasing: Ci, Cs and Cb | Cu |
| Precipitation | short period of showers | showers then clearing |
Why is it warm before a cold front?
Diagram showing a cold air front. As the cold front develops the warm air ahead of the front is pushed up over the top of the cold air. This happens because the warm air is lighter (less dense) than the cold air.
How does a cold front occlusion develop?
A cold occlusion occurs when the air behind the occluded front is colder than the air ahead of it. The cold air behind the front is less dense than the even colder air ahead of it, and so it passes over the top of the colder air.
What are the winds behind a cold front?
Development of cold fronts
| Weather phenomenon | Prior to the passing of the front | After the passing of the front |
|---|---|---|
| Winds | Southwest to southeast (northern hemisphere) Northwest to northeast (southern hemisphere) | North to west, usually northwest (northern hemisphere) South to west, usually southwest (southern hemisphere) |
What weather happens before a cold front?
What weather comes after a warm front?
Precipitation ahead of a warm front typically forms into a large shield of steady rain or snow. After the warm front passes, fair and milder weather is typical, however, a cold front is likely not far behind.
Why does it rain before a cold front?
As the warm air is pushed higher, the moisture it carries condenses and falls as rain. This is why a lot of heavy rain is produced along a cold front but once the cold air mass has come in this often abruptly changes to a clear spell of weather.
What happens when a cold front passes through?
When a cold front passes through, temperatures can drop more than 15 degrees within the first hour. Symbolically, a cold front is represented by a solid line with triangles along the front pointing towards the warmer air and in the direction of movement.
How are cold fronts different from warm fronts?
But, air masses aren’t just two-dimensional. They are three-dimensional blobs of air, so when cold air advances at the surface, cold air at higher altitudes also advances on warm air. Therefore, the narrow frontal zone that separates the two contrasting air masses must extend upward from the surface.
Which is the transition zone for a cold front?
A cold front is defined as the transition zone where a cold air mass is replacing a warmer air mass. Cold fronts generally move from northwest to southeast. The air behind a cold front is noticeably colder and drier than the air ahead of it.
How are cold fronts represented on weather maps?
Many backdoor cold fronts move cool, ocean air over warmer land regions. A cold front is easy to find on most weather maps. They are represented by a blue line with triangles popping off the right side of the blue line. The “L” you will see associated with cold fronts is an area of low pressure. Low pressure usually brings stormy weather.