Chapter 18: Upper Winds and the Jet Stream

Question 1

Jet Stream

How created? When is it a jetstream? What direction?

Answer 1

2 circulation cells (warm air high P, cold air low P)
Coriolis deviates air
Jet stream = wind > 60 kn
All travel east except tropical easterly

Question 2

Jetstreams (N Summer)

Answer 2

N Polar Front Jet (60° N, 150kn, FL300)
N Sub Tropical Jet (40° N, 70kn, FL400)
Tropical Easterly (10 - 20° N, 80kn, FL500)
S Sub Tropical Jet (30° S, 90kn, FL400)
S Polar Front Jet (50° S, 150, FL300)

Question 3

Jetstreams (N Winter)

Answer 3

Artic Front Jet (50 - 70° N, 80kn, FL200)
N Polar Front Jet (50° N, 200kn, FL300)
N Sub Tropical Jet (30° N, 90kn, FL400)
S Sub Tropical Jet (40° S, 70kn, FL400)
S Polar Front Jet (50° S, 120, FL300)

Question 4

Jetstream Dimension

Answer 4

2 nmi high
200 nmi wide
2000 nmi depth
1:100:1000

Question 5

CAT

Answer 5

CAT1: between jetstream and where cells meet
CAT2: above jetstream

Question 6

SIGWX Jetstreams
Elements noted (4)

Answer 6

> 80kn reported
core height stated
if large area > 80 kn -> noted
\ = change of 20kn or 3000’