Meteorology Lab 9 1) On a weather map, you may see these fronts. …

Meteorology Lab 9

1) On a weather map, you may see these fronts.  Identify each.  Define them.

2) Here is a cross-section view of a particular front.  What type of front could be pictured here?  Explain why in the box below.  

3) There is a second type of front that can appear to look like the above picture.  What is the other type of front?  Explain in the boxes below.

4) Here is a cross-section view of another front.  What type of front could be pictured here?  Explain why in the box below.  

5) In general, cold fronts are known for more severe weather.  A typical springtime cold front, where the air coming in from the north is still quite cold but the air coming in from the south has had a chance to warm up a lot, is known for a  large contrast in temperatures.  This creates severe conditions.  The clouds in this cold front are mostly of what type?

6) A steep boundary (see picture in problem 2) between the cold and warm air in the cold front means that the cold front creates a relatively narrow line of clouds.  See the satellite image below.  The symbol for the cold front is drawn on the image.

In the satellite image, which way is the cold air moving?

7) The warm front is known for a gentler (not as steep) boundary between warm and cold air (see picture in problem 4).  This leads to a more spread out cloud coverage.  The dominant clouds in this front are layered and called (name the basic type of cloud)

If these clouds are producing rain, they are called

The mid-latitude cyclone

Remember that a cyclone looks approximiately like the following.  Isobars are shown.  Low pressure is in the middle.  The surface wind direction spirals inward as shown (for the Northern Hemisphere).

On a map, if this cyclone is in the middle latitudes (not in the tropics near the equator), it is called a mid-latitude cyclone.  It is a large system.  So that you get a feel for the scale of this system, one is drawn in on the map below.  The cyclone pulls in air from all around, such as cold, dry air from the north (middle of Canada) and warm, humid air from the south (Gulf of Mexico), and cool, humid air from the east (Atlantic Ocean).

Because of how cold air is brought in from the north (cP air mass), there will be a cold front.  Warm air is brought up from the south (mT air mass), so there is a warm front.  Air is also pulled in from the east (mP air mass)

Remembering that a cold front gives us a fairly narrow band of clouds (usually with severe weather) and a warm front gives us spread-out layered clouds, the cloud coverage will be approximately like this:

These mid-latitude cyclones migrate across the country from west to east.

Day 1 Day 2     Day 3

We will now try to predict the weather day by day.  You will need to visualize the clouds and cloud types based on the pictures and information on previous pages of this lab.

Day 1:  What is happening at each location?

Day 2:  What is happening at each location?

Day 3:  What is happening at each location?