Exam 12: Middle-Latitude Cyclones

Divergence (or convergence)is a difficult task to measure with any degree of accuracy using upper-level wind information. Therefore, meteorologists must look for ____, something that can be measured and, at the same time, can be related to regions of diverging (and converging)air.

Vorticity refers to the ____.

Where maritime arctic air and colder continental arctic air meet, the boundary separating them is called a(n)____________________.

The entrance region occurs ____ of a jet streak, while the exit region occurs ____ of the jet streak.

Like hurricanes, polar lows normally have a warmer central core, strong winds (often gale force or higher), and heavy showery precipitation that unlike a hurricane, is in the form of snow.

When the wavelength of an upper-level wave is on the order of many thousands of kilometers, the wave is called a(n)____________________.

What does cyclogenesis mean, and where does it commonly occur?

Since the Northern Hemisphere's polar jet stream is strongest and moves farther south in ____, we can see why mid-latitude cyclonic storms are better developed and move more quickly during the ____ months.

In polar front theory, the region of warm air between the cold and warm fronts is known as the warm sector. Here, the weather tends to be ___________________.

When a deep upper-level trough is located to the east of a surface anticyclone, the surface anticyclone will tend to move toward the ____.

The Colorado Low forms (or redevelops)on the eastern side of the Canadian Rockies in Alberta, then rapidly skirts across the northern tier of US states.

As westerly winds blow over a north-south oriented mountain range, the airflow is deflected in such a way that a trough forms on the ____ side of the mountain.

A surface low pressure area with a deep upper-level trough to the west will tend to move toward the ____.

If we assume that the absolute vorticity of flowing air is conserved, air moving northeastward will bend ____ to compensate for the ____ in Earth's vorticity.

The development or strengthening of a middle latitude storm system is called ____.

Divergence aloft causes a(n)____________________ in the cyclonic (positive)vorticity of surface cyclones, which usually results in ____________________ and upward air motions.

Describe, in words or with a sketch, a wind flow pattern that will result in upper-level divergence.

Divergence aloft means that within this region, more air is entering than is leaving.

Rossby waves are also known as ____.

Another term for frontal wave is ____.