MET General

Question 1

What is the rule of thumb for altimeter error with changes in temperature

Answer 1

4% change per 10deg variation of ISA
Eg if temperature increases to ISA20 would mean altimeter underreads by 8%

Question 2

HPA at FL445

Answer 2

150

Question 3

HPA at FL385

Answer 3

200

Question 4

HPA at FL340

Answer 4

250

Question 5

HPA at FL300

Answer 5

300

Question 6

HPA at FL235

Answer 6

400

Question 7

HPA at FL185

Answer 7

500

Question 8

Validity of a SIGWX PROG

Answer 8

3 hours either side of the validity time stated

Question 9

Issue times GAF

Answer 9

4 times daily
2300Z -0500Z
0500Z - 1100Z
1100Z - 1700Z
1700Z - 2300Z

Question 10

GPWT Low level heights and issues

Answer 10

FL140
10000
7000
5000
2000
1000

Issue 4/times daily 2 hours before validity time starts. Starting from 0000Z and valid for 3 hours each

Question 11

RSWT Height format

Answer 11

FL
445
385
340
300
235
185

Question 12

ELR less than SALR

Answer 12

Absolutely stable

Question 13

ELR greater than DALR

Answer 13

Absolutely unstable

Question 14

ELR more than SALR but less than DALR
Eg ELR 2deg

Answer 14

Conditionally stable
Dry is stable
Saturated is unstable

Question 15

ELR and DALR is the same

Answer 15

Neutrally stable. It will remain at the same height once lifting force is moved

Question 16

Why does SE trades limit vertical buildup

Answer 16

Large scale subsidence over subtropical ridge creating a widespread inversion the the equatorial trough

Question 17

Drizzzle producing clouds

Answer 17

Stratus
Strataculumlus

Question 18

Shower producing cloud

Answer 18

Cumulus
Cumulinimbus

Question 19

Rain or virga associated cloud

Answer 19

Altostratus

Question 20

Continuos rain or snow cloud

Answer 20

Nimbostratus

Question 21

Cold front characteristic

Answer 21

Temperature drop
Backing wind
Pressure rise

Question 22

Warm front characteristics

Answer 22

Temperature rise
Backing wind
Pressure fall decreases

Question 23

What do warm airstreams cause

Answer 23

May generate inversions and stable conditions

Question 24

Cold airstreams characteristics

Answer 24

Results in steep ELR and instability

Question 25

Sub tropical jet location

Answer 25

30 deg south

Question 26

Low level jet in great dividing range

Answer 26

Western side in winter early morning with surface inversion, hazard is strong windshear

Question 27

Rime ice clouds and temperature

Answer 27

-10 to -20deg Strataform except Ns

Question 28

Clear ice clouds and temperature

Answer 28

0 to -15deg in cumuliform and thick As and Ns and orographic cloud

Question 29

What are microbursts associated with

Answer 29

Squall lines, TS and virga

Question 30

GAF cloud bases are amsl or agl

Answer 30

Amsl

Question 31

What are isotachs

Answer 31

Joins points of equal wind strength

Question 32

Shear thunderstorm

Answer 32

With enough vertical build a thunderstorm can survive a shear layer. The shear will make storm wider. Reducing friction between up and down drafts therefore increasing velocuty inside storm and greater turbulence

Question 33

Frontal or squall thunderstorms

Answer 33

Form as result of instability at boundary between two air masses they are closely spaced, low bases and fast moving. Also can have roll clouds form with frontalnactivity

Question 34

Air mass thunderstorms (orographic, cold stream, night equatorial)

Answer 34

More isolated than frontal/squall thunderstorms

Question 35

What conditions will a cold front bring

Answer 35

A fast moving cold front generates unstable conditions in the air ahead of it and can result in thunderstorms ahead of the front

Question 36

Weather associated with warm fronts

Answer 36

Generally stable resulting in stratiform clouds with rain from nimbostarus