Aviation Weather: Weather Charts

Question 1

What is Mean Sea Level (MSL)

Answer 1

your true altitude or the average height above standard

sea level

Question 2

What is Above ground level ( AGL)

Answer 2

the height above the ground over which you are flying

Question 3

Define SIGMET - Significant Meteorological Information

Answer 3

a weather advisory that
contains information about weather events like thunderstorms and severe
turbulence

Question 4

Define AIRMET - Airmen’s meteorological information

Answer 4

a weather advisory that
contains information about weather events that are potentially unsafe
- moderate turblulance
-high wind
-restricted visibility

Question 5

Visual Flight Rules (VFR)

Answer 5

basic VFR is defined as an airport having at

least a 1,000 foot ceiling and 3 statute miles of visibility

Question 6

Instrument flight rules (IFR)

Answer 6

is defined as an airport having less than

a 1,000 ceiling and/or less than 3 statute miles of visibility

Question 7

What is a the difference between Statue mile and Nautical mile?

Answer 7

Statute mile – legal definition of a mile (5280 feet)

Nautical mile - A unit of length used in sea and air navigation, based on the
length of one minute of arc of a great circle, especially an international and US
unit equal to 1,852 meters (about 6,076 feet)

Question 8

ASOS

Answer 8

primary surface weather observing system for the U.S. and

the data source for METARs and other aviation weather information

Question 9

AWOS

Answer 9

a weather reporting system that consists of various sensors and a transmitter to broadcast weather data

Question 10

What is a cloud ceiling

Answer 10

the altitude at the base of a cloud layer

FAA defines it as height of the lowest layer of clouds of the surface that are either broken or over cast but not thin.

Question 11

How do you calculate the cloud base?

Answer 11

Find the difference between the surface temperature and the dew point.

Divide result by 4.4 (if F) or 2.5 (if Celsius) am multiply by 1000

((Surface temp- dewpoint )/4.4 )* 1000

Question 12

Octals- how to figure out cloud coverage

Answer 12

Dive skydome into 8 parts. The observer is in the middle looking up.
number of sections with clouds determines cloud cover. Clear, few, scattered, broken, overcast.

Question 13

Types of Clouds: Cumulonimbus

What part of atmosphere?

Answer 13

Stretches from low to high altitude/ atmosphere. Big puffy cloud

Question 14

Types of Clouds: Cirrocumulus

What part of atmosphere?

Answer 14

High altitude/atmosphere.

Question 15

Types of Clouds: Cirrostratus

What part of atmosphere?

Answer 15

High altitude/ atmosphere

Question 16

Types of Clouds: Cirrus

What part of atmosphere?

Answer 16

High altitude

Question 17

Types of Clouds: Altocumulus

What part of atmosphere?

Answer 17

Mid altitude

Question 18

Types of Clouds: AltoStratus

What part of atmosphere?

Answer 18

Mid altitude

Question 19

Types of Clouds: Nimbostratus

What part of atmosphere?

Answer 19

Mid and low altitude

Question 20

Types of Clouds: Cumulus

What part of atmosphere?

Answer 20

Low

Question 21

Types of Clouds: Stratocumulus

What part of atmosphere?

Answer 21

Low

Question 22

Types of Clouds: Stratus

What part of atmosphere?

Answer 22

Low

Question 23

Cumulous Clouds
What are they like?
What kind of weather?
sUAS ranking?

Answer 23

Cumulus clouds are probably the most well-known of the
cloud types

generally form from convection, with air rising vertically into the and condensing
into the puffy, cotton-like clouds

Typically, cumulus clouds are associated with pleasant weather

Good for flying sUAS

Question 24

Cumulonimbus
What are they like?
What kind of weather?
sUAS ranking?

Answer 24

If updrafts become stronger, cumulus clouds may grow
taller into what we call cumulonimbus clouds

These are the towering clouds (up to 60,000 feet) mainly observed during the summer
months

Can be indicative of developing thunderstorms, including lightning, hail, heavy rain and
even tornadoes

Indicators that it might be time to call it a day; effects of weather from these
clouds can extend many miles from their center

UAS ranking: BAD!
If you see mammatus cloud development you should land your vehicle immediately
and be aware of rapidly changing and severe weather developments

Question 25

Stratus
What are they like?
What kind of weather?
sUAS ranking?

Answer 25

These clouds form when warm air is lifted over cold air, allowing for
uniform water vapor condensation

Looks like a layer blanketing the sky

Generally associated with wet conditions

Can last for days, bring cool temperatures, persistent rain, drizzle, or even snow

Great for imagery because the diffuse sun’s rays light all things evenly

UAS ranking:
Bad for flying if they are too low: ceiling and VLOS
Bad for flying from wet conditions

Question 26

Cirrus
What are they like?
What kind of weather?
sUAS ranking?

Answer 26

high, thin and wispy clouds very high up in the atmosphere
made up of tiny ice crystals.

Form out ahead of warm fronts and can be indicative of upcoming precipitation

Also develop as part of outflow from large scale storms including thunderstorm
complexes

Not bad for imagery because they filter sunshine

Can be bad for VLOS

Question 27

What is Airmass

Answer 27

An air mass is a large body of air

When air masses stay over a an area that has generally uniform temperature
and moisture characteristics from one day to the next the mass takes on those
same characteristics

Air masses form in places like polar regions, tropical regions and dry
deserts and are characterized by their temperature and moisture
content

When an airmass passes over a warmer surface convective currents
form creating unstable air with good visibility, increased turbulence,
cumulus clouds and potentially rain showers

When an airmass passes over a cooler surface convective currents do
not form creating stable air with poor visibility, low stratus clouds, fog
and/or steady precipitation

Question 28

What is a front?

Answer 28

The boundary air layer between two air masses or two areas of
pressure as they get nearer to one another is a front

Approaching fronts always means a change in the weather is
imminent preceded by changes in wind direction, speed and
temperature

Question 29

When does a Warm Front occur?

Answer 29

Warm fronts occur when a mass of warm air replaces a body of cooler air

Typically slow moving (10-25 mph) and can take days to approach and move on providing
advanced warning

Brings low ceilings, decreased visibility and

Question 30

When Does a Cold Front occur?

Answer 30

Occur when cold, dense, stable air replaces and body of warmer air

Typically fast moving, almost twice the speed of a warm front, at 25-30 mph

Bring violent weather

Question 31

What is a stationary Front?

Answer 31

When the force of two airmasses are equal the boundary remains
stationary

Can influence weather along the boundary for days

Weather generated along a stationary front can be a mixture of both warm and
cold front characteristics

Question 32

Occluded Front

Answer 32

Occurs when fast moving cold air catches up with slow moving warm air

Question 33

What are Isobars?

Answer 33

They are lines of constant pressure and the area inside the lines depict areas of equal pressure.