Significant Weather

Question 1

Prognosis and Analysis charts look the same, what does each chart show?

Answer 1

Prognosis forecasts the most probable weather conditions in the future, an analysis chart shows the actual conditions at a given time.

Question 2

Canadian Significant Weather (SIG WX) charts are for which range flights in Canada?

Answer 2

Mid to long range flights.

Question 3

Mid level charts covers what pressure and height range?

Answer 3

700 - 400 hPa and 10 000 - 24 000 ft

Question 4

What are the spatial coverages of convective cloud areas called and how much do they cover?

Answer 4

ISOLD: < 1/8 coverage
OCNL: 1/8 - 4/8 coverage
FRQ 5/8 - 8/8 coverage
RISK <50% of occurrence

Question 5

True or False?

Unlike the GFA charts, SIG WX charts depict freezing level at 2500’ increments.

Answer 5

False, SIG WX charts depict freezing levels with 5000’ increments. GFA use 2500’.

Question 6

World Area Forecast Centre (WAFC) SIG WX charts are for which range flights?

Answer 6

Long range flights.

Question 7

A WAFC SIG WX chart depicts weather from what flight level range?

Answer 7

FL 250 - 630

Question 8

WAFC SIG WX charts show the height of the tropopause in a closed box. What is the significance of the tropopause height?

Answer 8

It is the:

Level of max winds
Turbulence usually stops just above the tropopause
It is the top of most weather

Question 9

True of False?

SIG WX charts:

a) Often indicate trends or motions of clouds
b) They do not provide landing weather like a TAF does
c) Significant weather charts are amended if necessary

Answer 9

a) False, they do not often
b) True, they do not
c) False, they are not amended

Question 10

What is a FACN31 CWHF?

Answer 10

A text version of a GFA for the Dip Sector area off the coast of Shearwater.

Question 11

In the FACN31 XWHF, is the freezing height AGL or ASL?

Answer 11

ASL

Question 12

Forecasted upper winds and temperatures are from the surface to which height?

Answer 12

6000 ft