Ground 1 Exam 3

Every physical property of weather is caused by…

heat exchange

When there’s a temperature inversion, what can you expect?

An increase in temperature occurs as altitude increases

What causes the wind direction at the surface to be different from at altitude?

Surface friction

What is the dew point?

The temperature in which the air is completely saturated/wet

What will determine how much water vapor the air can hold?

Temperature

Clouds, fog, and dew will always form when…

Water vapor condenses

Name two processes that add moisture to unsaturated air.

Evaporation and sublimation

How does frost form?

When the temperature meets the dew point and is below freezing

Ice pelts on the ground mean…

there is a temperature inversion

What do we measure to determine if an air mass stable?

Lapse rate

Characteristics of stable air:

bad visibility, straitform, steady rain, steady precipitation

If you take more moist air and force it up slowly, what do you get?

Steady precipitation and stratus clouds

Convergence rate formula

(Temp - dew point)/4.4= answer x1,000

Nimbus means

rain

When you cross a front, what is most likely to occur?

A change in winds or a change in temperature

What weather phenomenon will always occur when flying across a front?

Wind changes

Static precipitation in front of a front normally indicates…

stable, nonturbulant, status clouds

When temperature and dew point are close, what is likely to happen?

Fog and clouds

What causes a sea breeze?

When the land is hotter than the sea, causing low pressure on land and high on the ocean

Lens shaped clouds that denote mountain waves.

Lenticular or a standing lenticular

What clouds have the greatest turbulence?

Towering

What kind of cloud can indicate convective turbulence?

Cumulous

If wind is blowing 40 knots or greater across a mountain, what could you expect to happen?

Mountain waves, but it has to be stable

Where does wind sheer occur?

At any altitude at any time

What do you need for ice to form?

Below freezing temperatures on the surface and visible moisture

What weather phenomenon causes the highest accumulation rate of ice?

Freezing rain

Why is ice considered dangerous?

It adds weight and changes the shape of the airfoil, decreasing lift, and spoils airflow

What are the three things that make a thunderstorm?

Lifting action, unstable air, and moisture

What characteristics are primarily associated with the cumulus stage of a thunderstorm?

Updrafts. Mature stage is ups and down drafts and rain hits the surface.

During the lifestage of a thunderstorm, which stage is primarily characterized by downdrafts?

Dissipating

What two cloud layers constitute a ceiling?

Broken and overcast

If you have not gotten the weather briefing and you leave in an hour, what kind of weather briefing are you gonna ask for from a flight service station?

Ask for standard flight form

What would contain information about severe icing that’s not associated with a thunderstorm?

Sigmet

Moderate icing not associated with a thunderstorm →

Airmet

What is VFR weather?

No more than 1,000 ft ceiling, more than 3 statue miles

If you read it, it’s

true.

If you hear it, it’s

magnetic.

Does a METAR report clouds in an MSL or an AGL?

AGL

So the field of elevation is at an AGL?

1,300

What are the clouds in MSL?

9,300

What’re the two types of taf duration, how long are they valid for?

Posted every 6 hours, valid for 24 to 30.

What does 9900 mean?

Light and variable winds

What is the direction and speed for KWA at 1,000 feet?

110

Temps negative at or above…

24,000 ft