Question 166-1 : The following statements deal with precipitation turbulence and icing select the list containing the most likely alternatives for ns cloud ? [ Formation assignment ]

Question 166-2 : From what type of cloud does drizzle fall ?

Stratus.

Stratus does not usually produce precipitation but when it does occur it is in the form of minute particles such as drizzle ice crystals or snow grains

Question 166-3 : What type of clouds are associated with rain showers ?

Towering cumulus and cumulonimbus.

Shower rainsnow towering cumulus cumulus and cumulonimbuscontinuous rainsnow nimbostratusshower rain short duration rain

Question 166-4 : What type of clouds are associated with snow showers ?

Cumulus and cumulonimbus.

Shower rainsnow towering cumulus cumulus and cumulonimbuscontinuous rainsnow nimbostratusshower rain short duration rain

Question 166-5 : Which of the following phenomena should be described as precipitation at the time they are observed ?

Dz.

Question 166-6 : Which of the following phenomena should be described as precipitation at the time they are observed ?

Shsn.

Shsn snow showerva volcanic ashbr mistmifg shallow fog

Question 166-7 : Solid precipitation which is transparent or translucent and has a diameter of 5mm or less formed by the freezing of raindrops or refreezing of melted snow and usually bounces off hard surfaces is a description of ?

Ice pellets.

Question 166-8 : During flight in clouds which of the following means is the best one to identify the position of embedded cbs ?

Weather radar.

Question 166-9 : Which of the following statements concerning airborne weather radar is correct ?

It shows on a plan position indicator the areas of precipitation of rain snow andor hail.

Cqb15 august 2011

Question 166-10 : Snow grains ?

Fall from stratus or supercooled fog.

Stratus does not usually produce precipitation but when it does occur it is in the form of minute particles such as drizzle ice crystals or snow grains

Question 166-11 : Which of the following statements is true concerning the bergeron findeisen process ?

It only takes place in clouds with supercooled water droplets and ice crystals.

The bergeron findeisen process can be summarized as such the air reaches saturation and some of the resulting droplets will come in contact with freezing nuclei assuming they have reached the activation temperature we will now have a combination of ice crystals and supercooled water droplets from the perspective of the supercooled droplets the air is in equilibrium at saturation but from the perspective of the ice crystals the air is supersaturated therefore water vapor will sublimate on the ice crystals since the amount of water vapor in the air has decreased and from the perspective of the supercooled water droplet the air is subsaturated the supercooled water will evaporate until the air once again reaches saturation the process then continues in short summary the ice crystal grows through sublimation at the expense of the supercooled water droplet

Question 166-12 : Which of the following statements is true concerning the coalescence process ?

In the mid latitudes this process produces only drizzle or very light rain.

Cloud droplets are carried by air currents within the cloud if they bump into each other it is called a collision however if they collide then stick together that is called coalescencethis process is important especially in the tropics and in increasing the size of raindrops it falls short of being the primary mechanism for the formation of raindropsthe collision coalescence process is of relatively little importance in middle and high latitudes where even in the summer precipitation begins high in the clouds where temperatures are well below freezing and the dominant precipitation producing mechanism is the so called ice crystal or bergeron process

Question 166-13 : The processes andor effects which cause clouds to release precipitation are ?

Coalescence process and bergeron findeisen process.

Quick overview of precipitation formation processes click here to open the video in a new window

Question 166-14 : State the code used to indicate moderate precipitation in the form of snow flakes from a cumulonimbus cloud ?

Shsn.

Ecqb03 july 2016

Question 166-15 : The size of a drizzle droplet ?

Less than 05 mm.

Ecqb03 july 2016drizzle is a slowly falling precipitation in the form of tiny water droplets with diameters less than 05 millimeters it falls from stratus clouds and is often associated with low visibility and fog stratus does not usually produce precipitation but when it does occur it is in the form of minute particles such as drizzle ice crystals or snow grains

Question 166-16 : The presence of ice pellets at a height of 8000 ft indicates ?

Freezing rain at heights above 8000 ft.

Ecqb03 july 2016

Question 166-17 : The weather most likely to be experienced at position 'q' is 414 ?

Showery with generally good visibility.

Question 166-18 : Which statement best describes coalescence ?

Droplets velocity increases with their radius those who have grown faster will fall faster than others and will sweep smaller droplets.

Question 166-19 : Which of the following is typical for the passage of an active cold front in the summer ?

Mainly towering clouds.

An active cold front is pushing warm moist air up from underneath producing some layered cloud but almost always cumulus cloud and turbulent weather 639when the front has passed through the air is now cold and therefore more dense and dense air is higher pressure

Question 166-20 : Examining the pictures on which one of the tracks dashed lines is this cross section to be expected 250 ?

Track b d.

Only one dashed line crosses two fronts a cold front and a warm front

Question 166-21 : Frontal depressions can be assumed to move in the direction of the 2000 feet wind ?

In the warm sector.

508the isobars in the warm sector tend to be parallel and straight and give an indication in the direction of the system until it occludesisobars indicate the direction of the wind at least at 2000 ft above the surface the free stream unaffected by surface friction

Question 166-22 : What types of cloud will you meet flying towards a warm front ?

At some 800 km cs later as and at some 300 km ns until the front.

505when approaching an active warm front at medium to low level you can expect a low cloud base poor visibility and rain

Question 166-23 : The polar front is ?

The boundary between polar and tropical air masses.

The polar front is the boundary between polar air and tropical air 595

Question 166-24 : What are the typical differences with regard to the temperature and humidity between an air mass with its origin in the azores and an air mass with its origin over northern russia ?

The air of the azores is warmer and more humid than the north russian air.

Question 166-25 : Where is the source of continental tropical air that affects europe in summer ?

The southern balkan region and the near east.

Question 166-26 : Where does polar continental air originate ?

Siberian landmass.

Question 166-27 : What type of fronts are most likely to be present during the winter in central europe when temperatures close to the ground are below 0°c and freezing rain starts to fall ?

Warm fronts warm occlusions.

Freezing rain is associated with warm fronts and warm occlusions in a warm front the freezing level is lower than behind in the warm sector and the slope means that freezing rain will be falling on anything underneath so if you are flying towards a warm front or warm occlusion watch out supercooled water droplets from above will freeze onto your cold airframe once you see ice pellets expect freezing rain next 505

Question 166-28 : Which of the following conditions are you most likely to encounter when approaching an active warm front at medium to low level ?

Low cloud base and poor visibility.

505when approaching an active warm front at medium to low level you can expect a low cloud base poor visibility and rain

Question 166-29 : During a cross country flight at fl 50 you observe the following sequence of clouds nimbostratus altostratus cirrostratus cirrus which of the following are you most likely to encounter ?

Decreasing temperatures.

The cloud types described will be found in a warm front 506you are flying from the warm sector through the warm front in direction of the cold sector the outside temperature will be decreasing

Question 166-30 : What cloud formation is most likely to occur at low levels when a warm air mass overrides a cold air mass ?

Nimbostratus.

a warm air mass overrides a cold air mass this is a warm front 505at low levels you will have stratus and nimbostratus

Question 166-31 : The approximate inclined plane of a warm front is ?

Is 1150.

628the slope of a warm front 1150 is lower than the one of the cold front 150

Question 166-32 : What type of low pressure area is associated with a surface front ?

Polar front low.

An area of low pressure found together with a surface front is a 'frontal depression'frontal depressions are mid latitude weather systems formed due to differences in temperature and pressure of adjacent or converging air masses those frontal depression born on the front between polar and temperate air masses create a warm front where the warmer air rises over the colder one then trail a cold front behind it

Question 166-33 : In which approximate direction does the centre of a non occluded frontal depression move ?

In the direction of the warm sector isobars.

A question uses the following annex and asks where will move the frontal depression 507answer is n°3 508the isobars in the warm sector tend to be parallel and straight and give an indication in the direction of the system until it occludes

Question 166-34 : Where is the coldest air to be found in an occlusion with cold front characteristics ?

Behind the front.

Question 166-35 : What type of front occlusion usually moves the fastest ?

Cold front.

621

Question 166-36 : What weather conditions are prevalent during the summer over the north sea approximately 300 km behind a quickly moving cold front ?

Cloud cover mostly scattered isolated showers.

Question 166-37 : What is the surface visibility most likely to be in a warm sector of maritime tropical air during a summer afternoon in western europe ?

Moderate several km .

The warm sector is invariably tropical maritime air mass warm moist and stable visibility is generally not good but on a warm summer afternoon the air becomes less stable the relative humidity decreases and visibility improves

Question 166-38 : After passing at right angles through a very active cold front in the direction towards the cold air what will you encounter at fl 50 in the northern hemisphere immediately after a marked change in temperature ?

A veering in the wind direction.

In the northern hemisphere the air flows anti clockwise around a depression 509if you are flying through the cold front from the warm sector to the cold sector at right angles the wind which was previously from the left of your nose becomes from the right of your nose that means the wind direction has increased in heading so that is veering

Question 166-39 : Which one of the tracks dashed lines is represented by the cross section shown on the left 258 ?

Track d a.

Track d a corresponds to a warm occlusion 628with a warm occlusion cold front rides up and over the warm frontif the line of the occlusion is approximately along the same line as the warm front then we have a warm occlusion 512

Question 166-40 : Which cross section of air mass and cloud presentation is applicable to the straight line a b 259 ?

N°3.

N°1 cold front and n°4 warm front are out line a b is an occlusionn°3 is a warm occlusion and n°2 a cold occlusioncold front rides up and over the warm front 512if the line of the occlusion was approximately along the same line as the warm front then we have a warm occlusion n°3