Cyclones/ Fronts

Question 1

What are cyclones?

Answer 1

are low pressure cells

Question 2

What are the three types of cyclones?

Answer 2

1. Mid-Latitude (MLC)
2. Tropical
3. Tornado

Question 3

What are the characteristics of all cyclones?

Answer 3

• areas of surface LOW Pressure
• surface convergence of winds
• ascending air
• clouds and PPT
• counterclockwise in N. Hemi, opposite in S

Question 4

What are the characteristics of anticyclones?

Answer 4

• High Pressure
• descending air
• surface divergence of winds•clockwise flow in N. Hemisphere•clear weather—High and Dry!

Question 5

Where do air masses form?

Answer 5

1. Over oceans
2. Large snow surfaces, like Canada & Siberia in winter
3. Sometimes over big, dry deserts

Question 6

What is the flow for cyclones and anticyclones?

Answer 6

Air flows into Low pressure out of High pressure.

Question 7

What is the flow of cyclones and anticyclones in the northern hemisphere?

Answer 7

In high pressure, anticyclonic divergent clockwise flow

In Low pressure, cyclonic convergent counterclockwise flow

Question 8

What is the flow of cyclones and anticyclones in the southern hemisphere?

Answer 8

In high pressure, anticyclonic divergent counterclockwise flow

In Low pressure, cyclonic convergent clockwise flow

Question 9

Where do these cyclones occur?

Answer 9

The two larger phenomena, Tropical and MLCs occur in different places on earth. Tornadoes also occur mainly in the mid-latitudes (and sometimes subtropics)

Question 10

What are the properties of air masses?

Answer 10

1. LARGE -may be>600 mi. across
2. nearly UNIFORM air in terms of temperature, moisture, pressure-The air mass is distinct from surrounding air
3. The Air mass moves as a UNIT

Question 11

Where do air masses form and where do they move to?

Answer 11

Are formed in 60 degree latitude and move to equator

Question 12

What are the four main air mass types?

Answer 12

• cP–continental Polar
• mP–maritime Polar
• cT–continental Tropical
• mT–maritime Tropical

Question 13

How do the air masses types get their names?

Answer 13

From their source regions! Like winds we name them from where they come

Question 14

What does the latitudinal position do for air mass types?

Answer 14

Latitudinal Position –determines temp.Polar or Tropical (P or T)

Question 15

What does underlying surface do for air mass types?

Answer 15

Underlying Surface—Water or Land?–determines the amount of moisture associatedMaritime or Continental (m or c)

Question 16

What air masses are most important to weather here in blacksburg?

Answer 16

cP and mT

Question 17

Do air masses mix?

Answer 17

No!

Question 18

What is a front?

Answer 18

The boundary between air masses

Question 19

What are fronts a component of?

Answer 19

Mid-latitude cyclones (MLCs)

Question 20

What are MLCs?

Answer 20

MLCs are areas of low pressure that move across the earth

Question 21

What is some classic weather associated with fronts?

Answer 21

A –Modified cool air mass. Lowering clouds. Nimbostratus near front, light, steady rain poss. as front approaches, Winds-NE-E-SE
B –Warm air sector (mT). Fair, Humid, Warm/hot
Winds S
C –Cumulonimbus along cold front,Heavy rain, Severe weather possible along the front
D -Cold air sector (cP)Clear, Cool/cold Dry, H press Winds W-N

Question 22

How does air flow in cyclones and anticyclones?

Answer 22

Look at powerpoint, page 38

Question 23

What happens in MLCs?

Answer 23

• 3 air masses involved
• Warm front leads
• Warm air rises over cold at both fronts

Question 24

What is a classic warm front?

Answer 24

Warm air moves into area occupied by cooler air—slides up over cold

Question 25

What are some characteristics of a classic warm front?

Answer 25

• Note the LOW ANGLE that stretches out clouds far from front
• CIRRUSand LOWERING CLOUDS way out ahead, signal the arriving front
• WIDE BANDsteady precip, STRATUSclouds at front

Question 26

What is a classic cold front?

Answer 26

FRONTCold air advances into area occupied by warm air—pushes up warmer air, sometimes VIOLENTLY

Question 27

What are some characteristics of a cold classic cold front?

Answer 27

• Steep slope, rapid movement, passes quickly
• Narrow band of precip, cumulo-type clouds
• sometimes severe weather, T-storms, tornados

Question 28

What is some classic weather associated with fronts?

Answer 28

A –Modified cool air mass. Lowering clouds. Nimbostratus near front, light, steady rain poss. as front approaches, Winds-NE-E-SE
B –Warm air sector (mT). Fair, Humid, Warm/hot
Winds S
C –Cumulonimbus along cold front,Heavy rain, Severe weather possible along the front
D -Cold air sector (cP)Clear, Cool/cold Dry, H press Winds W-N

Question 29

What is a classic mid-latitude cyclone?

Answer 29

“comma”shape and heavy cloud cover all around the center of the lowcP

Question 30

What is the life cycle of a mid-latitude cyclone?

Answer 30

About four days

Question 31

How does a mid-latitude cyclone begin and end?

Answer 31

Begins with cold front “chasing” warm front. It ends with occluding, cold front (the faster front) catching the warm front.

Question 32

What does the zone of westerlies do in the n. hemisphere winter?

Answer 32

Zone of Westerlies(belt where ML Cyclones occur) moves equatorwardduring N. Hemi winter

Question 33

What are special storms?

Answer 33

Onshore flow (NE) of Atlantic moisture meets cold air from H press system

Question 34

What are some effects of special storms?

Answer 34

• Lots rain
• Lots snow & ice
• HIGH winds-Waves
• Coastal flooding