Lesson 22 - Meteorological Info

Question 1

Where are the two World Area Forecast Centres?

Answer 1

London and Washington

Question 2

What info will meteorological offices issue?

Answer 2

Terminal Area Forecast
- TAF (Rumour)

Question 3

What info will meteorological stations issue?

Answer 3

METAR (Truth)

Question 4

Name the three warnings that meteorological watch offices might issue

Answer 4

SIGMET
AIRMET
ASHTAM

Question 5

VAAC stands for what?

Answer 5

Volcanic Ash Advisory Centres

Question 6

TCAC stands for what?

Answer 6

Tropical Cyclone Advisory Centres

Question 7

World Area Forecast Centres provide what type of forecast?

Answer 7

Upper-air gridded forecast

Question 8

How often do WAFCs issue significant weather charts?

Answer 8

6-9 hours

Question 9

Meteorological Offices issue TAFs how often and how long are they valid for?

Answer 9

3 or 6 hours

Valid between 6-30hours

Question 10

How often is a METAR produced?

Answer 10

30 or 60mins

Question 11

What is a SPECI

Answer 11

interim METAR due to significant change

Question 12

What is a TREND?

Answer 12

Mini forecast valid for 2 hours. Also known as LANDING FORECAST

Question 13

What is a SNOWTAM?

Answer 13

Warning of airfield condition due to snow/slush/ice valid for up to 8 hours

Question 14

What is an AERODROME WARNING (ADW)?

Answer 14

Warning of conditions affecting aircraft such as vehicles, debris and facilities on ground etc.

Question 15

What is a SIGMET?

Answer 15

Significant level of change in the upper level valid for 4-6 hours, produced by met watch office (MWO). 4hours generally, 6 only if volcanic or cyclone activity also present.

SIGnificant METeorological change

Question 16

What is an AIRMET?

Answer 16

Report of weather produced by pilots at low level FL100/150 valid for 4 hours

Question 17

What is an ASHTAM?

Answer 17

Report of volcanic activity & ash clouds valid up to 24h

Question 18

What conditions will a SIGMET report on?

Answer 18

Thunderstorms (TS)
Tropical Cyclone (TC with +34kt crosswinds)
Severe Turbulence
Severe Icing (inc SEV due FZRA)
Severe Mountain Waves
Heavy Sand or Dust storm (SS, DS)
Volcanic Ash (VA)
Radioactive Cloud (RDOACT)

Question 19

Who is responsible for issuing a SIGMET?

Answer 19

Meteorological Watch Office (MWO)

Question 20

What does a TREND do?

Answer 20

Supersedes any current TAF for 2 hours, known as landing forecast. Found at end of METAR or SPECI (TEMPO)

Question 21

What conditions must exist for a CAVOK to be issued?

Answer 21

No cloud below 5000ft or 1000ft above highest obstacle MSA (minimum safe altitude), whichever is greater
Visibility 10km or more
No CB or TCU at any height
No significant weather phenomena eg blowing snow, tornadoes etc.

Question 22

What is a jet stream?

Answer 22

Bands of strong winds that generally blow from east to west and are found at the top of the troposphere

Question 23

When the maximum speed of a jet stream core is in excess of 120kt additional information indicating the flight levels between which the wind is equal to or in excess of ____ is given

Answer 23

80kt

Question 24

If there is insufficient space on the jet stream to display a full wind symbol, a change bar is (—//—) used whenever the jet stream changes by_____

Answer 24

+/-20kt or +/-3000ft

Question 25

What is the okta scale for clouds (except CB)?

Answer 25

FEW - 1/8 to 2/8
SCT - 3/8 to 5/8
BKN - 5/8 to 7/8
OVC - 8/8

Question 26

Winds reported by the control tower and in ATIS reports are averaged over the previous how many minutes?

Answer 26

30 min

Question 27

Surface wind measurements contained in METAR and SPECI reports are averaged over the previous how many minutes?

Answer 27

10 mins

Question 28

The ATS unit gives instantaneously winds at airports used by traffic with a MTOM greater than how many kg?

Answer 28

5700kg