Weather Flashcards

Question

Precipitation/weather type Surface analysis chart valid 3 hrs

Answer 1

Heavy Rain

Answer 2

First symbol Freezing Rain Second symbol is Drizzle

Answer 3

Humidity, Temperature, and Altitude affect density altitude

Answer 4

* provides a forecast of aviation hazards * covers the CONUS * Depicts: Flying categories, Turbulance, Freezing Levels * Snap Shot issued 12 hrs and 24 hr prog * 4x/day

Answer 5

Rain Shower

Answer 6

Rain/Snow shower

Answer 7

Sky Coverage Info Missing

Answer 8

Total sky obscuration (fog)

Answer 9

* Light Snow * Moderate Snow * Heavy Snow

Answer 10

Breaks in Overcast

Answer 11

Moderate Rain

Answer 12

Light Rain

Answer 13

1) Wind from Northwest @ 10 knots 2) Wind from South @15 knots 3) WInd from Northeast @ 65 knots

Answer 14

1) areas with shading indicate IFR conditions 2) Contoured areas without shading indicate MVFR 3) No count ours or shading indicate VFR conditions

Answer 15

Add half the gust factor to speed gust factor: 18-8 = 10 half of 10 = 5 Normal approach speed = 70 + 5 = 75 kts

Answer 16

Standard = Contains 7 elements: 1) Adverse Conditions 2) Synopsis 3) Current Conditions 4) Enroute forecast 5) Destination Forecast 6) winds aloft 7) Notams Abbreviated = Request an Abbreviated Briefing when you need information to supplement other electronically acquired data (e.g., TIBS or DUATs), update a previous briefing, or when you need only one or two specific items. Outlook = For future flights in 6 hours. This type of briefing is provided for planning purposes only. You should obtain a Standard Briefing as close to departure as possible in order to obtain the latest current conditions, forecasts, and NOTAMs.

Answer 17

RAIM (Receiver Autonomous Integrity Monitoring) is also used to establish if the GPS receiver can depend on the position. RAIM only deals with the horizontal position and not the vertical. RAIM works by using 4 satellites to obtain a position. If a fifth satellite is available, RAIM can be calculated by the GPS receiver by substituting the fifth satellite in place of each of the other satellites, replacing one at a time. This provides 5 positions. The closer all the positions are to one another, the more you can depend on the position. This can also be done with additional satellites and can be augmented by the barometric altitude as an input to the algorithm. Sometimes, the geometry of the satellites don’t allow for determining a good position or the number of satellites in view can cause this as well. RAIM is used by the standard GPS and WAAS HPL/VPL is used by a WAAS GPS. If for some reason, the WAAS signal can’t be received, the WAAS GPS defaults to a non WAAS mode of operation and RAIM is used. But for the vast majority of the time, WAAS is available and it is used instead of RAIM.

Answer 18

Convective SIGMETs are issued in the conterminous U.S. if these conditions are occurring or expected to occur: Line of thunderstorms at least 60 miles long with thunderstorms affecting 40% of its length. Area of thunderstorms covering at least 40% of the area concerned and exhibiting a very strong radar reflectivity or a significant satellite or lightning signature. Embedded or severe thunderstorms expected to occur for more than 30 minutes. Special issuance criteria include: tornado hail greater than or equal to 3/4 inches in diameter wind gusts greater than or equal to 50 knots Any convective SIGMET implies severe or greater turbulence, severe icing, and low level wind shear. A convective SIGMET may be issued for any convective situation which the forecaster feels is hazardous to all categories of aircraft. Bulletins are issued hourly at Hour+55. The text of the bulletin consists of either an observation and a forecast or just a forecast. The forecast is valid for up to 2 hours.

Answer 19

Terminal Aerodrome Forecasts (TAFs) are concise statements of the expected meteorological conditions within a 5 SM radius from the center of an airport's runway complex TAFs can be found on the National Oceanic and Atmospheric Administration's (NOAA's) website at http://www.aviationweather.gov/adds/tafs or through use of the java tool here TAFs can be retrieved in the raw coded format or a translated (decoded) format [Figure 1] TAFs and Routine Aviation Weather Reports (METARs) are very similar but deviate as wind shear, temperature, icing, and turbulence groups are added to the TAF, when applicable There are two types of TAF issuances: Routine forecast issuance (TAF), and; Amended forecast (TAF AMD) An amended TAF is issued when the current TAF no longer adequately describes the on-going weather or the forecaster feels the TAF is not representative of the current or expected weather Corrected (COR) or delayed (RTD) TAFs are identified only in the communications header which precedes the actual forecasts

Answer 20

* Low clouds go from SFC - 6500 = Stratus, Stratocumulus, Nimbostratus * Middle Clouds go from 6500 AGL - 20,000 Alto Stratus, Alto Cumulus * High Clouds go higher than 20,000 ft AGL: Cirrostratus, CIrrocumulus, Cirrus * [https://www.cfinotebook.net/notebook/weather-and-atmosphere/clouds](https://www.cfinotebook.net/notebook/weather-and-atmosphere/clouds) Cumulonimbus are the most dangerous. Classified by the height of their bases

Answer 21

1013.2 15 degrees Celsius 29.92 altimiter

Answer 22

Wind shear is the rate of change of wind velocity (Direction and or speed) per unit distance. Expressed as vertical or horizontal windshear. Can occur at any level in atmosphere but special concerns toward: 1. Windshear with low level temperature inversion 2. Wind shear in frontal zone/T-storm 3. Clear air turbulence @ high levels with Jet stream or strong circulation

Answer 23

Routine Amended and Corrected

Answer 24

Terminal Radar Service area * Delimited area - airspace in which radar and ATC services are made available to pilots flying IFR/VFR for maintaining Separation * Depicted as Gray shaded area * Radar Sequencing and Separation Service: Implemented at certain terminal locations Service is advertised in the Chart Supplement U.S. Provides separation between all participating VFR and all IFR aircraft operating within the airspace defined as Terminal Radar Service Area (TRSA) Pilot participation is urged but not mandatory If an aircraft does not want this service then state "Negative TRSA Service" on initial contact or as appropriate VFR aircraft will be separated from VFR/IFR aircraft by one of the following: 500' vertical separation Visual separation Target resolution (a process to ensure that correlated radar targets do not touch) when using broadband radar systems Participating aircraft must maintain an altitude when assigned, ATC may assign altitudes that do not conform with 91.159 (VFR cruising altitude or flight level) When altitude restriction no longer applies ATC will advise "Resume Appropriate VFR Altitudes" Pilots must then return to appropriate 91.159 altitudes as soon as practicable When not assigned an altitude, the pilot should coordinate with ATC prior to any altitude change

Answer 25

1. Structural: Ice accumulating on aircraft itself 2. Induction: on the system, carburator icing 3. Instrument: Pitot/Static ports. Pitot gets cold= pitot heat. Static has alternate static source on 172S

Answer 26

* Is an aviation warning for us by aircrews to anticipate & avoid adverse weather conditions * 2 hour period * 2 hour valid peirod *

Answer 27

* Aviation routine weather report * Rapidly changing weather conditions aircraft mishaps or critical information * Meteorological Terminal Aerodome Report of current weather information released every hour

Answer 28

Potential hazardous to all aircraft. Issued when necessary and valid for 4 hours Severe Icing Severe Turbulance Dust

Answer 29

* TAF * METAR * LLWAS * Sigmet & Convective Sigmet * PIREPS

Answer 30

Amount of moisture available, the degree of stability forced upward, speed of the front & Upper wind flow.

Answer 31

Forcast for specific locations issued 4 times a day winds are not issued for altitudes within 1500ft of a location

Answer 32

Observation & Forecast valid for 2 hours Severe thunderstorms due to: * Surface winds greater than 50 kts * hail 3/4” * Tornadoes * Embeded Thunderstorms * Squal Line * TS Affecting 40% area 3,000 square miles

Answer 33

* Occur in the troposphere which extends from surface to 36,000 ft * 15 degrees Celsius - 56.5 degrees Celsius

Answer 34

* Ability to resist vertical motion * stable atmosphere makes vertical movement difficult * unstable atmosphere small vertical air movement tends to become larger: leads to turbulence, extension vertical clouds, severe weather.

Answer 35

Occurs when a mass of cold dense and stable air advances and replaces a body of warmer air. * Fast moving 30mph * cumulus clouds * thunderstorm * gust * turbulance * 25-30 mph * hail * tornadoes *

Answer 36

visible moisture in the form of clouds, dew or fog

Answer 37

The stability of the atmosphere

Answer 38

Plot of weather conditions at selected METAR stations * IFR * MVFR * VFR * LIFR

Answer 39

* Stable Lapse Rate of 2degrees Celsius per 1,000 ft * Unstable more than 2 degrees Celsius per 1000 ft ex: 3degrees Celsius 1,000 ft Warm & moist air

Answer 40

1. Clear Air Turbulence CAT normally occurs outside of clouds at altitudes above 15,000 feet MSL, and its caused by strong wind shears in the jet stream. 2. Thermal Turbulence Localized columns of convective current (picture a rising column of warm air) result from surface heating or cold air moving over warmer ground. For every rising current, there is a compensating downward current usually slower in speed, since it covers a broader area, causing turbulence. 3. Temperature Inversion Turbulence Even though a temperature inversion produces a stable atmosphere, inversions can cause turbulence at the boundary between the inversion layer and the surrounding atmosphere. 4. Mechanical Turbulence When the air near the surface of the Earth flows over obstructions, such as bluffs, hills, mountains, or buildings, the normal horizontal wind flow is disturbed and transformed into a complicated pattern of eddies and other irregular air movements. 5. Frontal Turbulence Frontal turbulence is caused by lifting of warm air, a frontal surface leading to instability, or the abrupt wind shift between the warm and cold air masses. The most severe cases of frontal turbulence are generally associated with fast-moving cold fronts. 6. Mountain Wave Turbulence As air flows over the tops of mountains, traveling down the leeward side, a standing mountain wave is formed and air currents oscillate between altitudes. Mountain waves and turbulence can extend for hundreds of miles downwind of the mountain range. 7. Thunderstorm Turbulence The storm cloud is only the visible portion of a turbulent system in a thunderstorm. But updrafts and downdrafts often extend outside the storm, with severe turbulence possible as much as 15 to 30 miles downwind.

Answer 41

* FSS * ATIS * HIWAS * ATC

Answer 42

Pilot Report or PIREP is a report of the actual weather conditions as encountered by an aircraft in flight. Traditionally, these reports are transmitted by radio to an appropriate ground station for dissemination but, when necessary, they can be made by telephone after landing. FSS ATC Aviation Wx.gov Weather Briefer

Answer 43

The temperature at which air can no longer hold moisture ## Footnote Once the relative humidity of a mass of air becomes 100%, then if the temperature falls it cannot hold all of the water vapour within it. The excess water vapour will then condense into cloud or fog or, if in contact with objects on or near the ground, will form dew or hoar frost. When observing successive weather reports (METARs), a reducing gap between the actual temperature and the Dew Point temperature gives an indication of impending low visibility conditions and the posibility of fog.

Answer 44

because unexpected changes in wind speed & direction can be potentially hazardous to aircraft operation at low altitudes on approach to and departing from airports

Answer 45

Automatic Terminal Information Service: recording that some airports broadcast in order to reduce frequency congestion. Current weather information, active runway information, NOTAMs, and other useful pieces of information are included in the ATIS. The ATIS is usually updated every hour or when there is a sudden weather change at the airport. ATIS is how pilots get the latest information about an airport over the radio and this is simulated in VATSIM.

Answer 46

* Increase in headwind: * As a tailwind shears to a constant headwind an increase in airspeed and altitude occurs along with a pitching tendency * reaction is to pull power and reduce pitch but the situation calls for the exact opposite * Sudden decrease * Add power and higher pitch attitude to continue * Climb to remain on the glideslope

Answer 47

1. Sierra: IFR & Mountain Obscuration 2. Tango: Moderate turbulance or low level wind shear 3. Zulu: Moderate Icing

Answer 48

1. Sigmet 2. Convective Sigment 3. Airmet 4. Center Weather advisories

Answer 49

ceiling 500 to \< 1,000 feet AGL and/or visibility 1 to 3 s.m.

Answer 50

Manual Observation Reports made from airport locations staffed AWOS: Computer generated voice weather data updated minute to minute ASOS: minute to minute observation necessary to generate METARS and other aviation weather information

Answer 51

The boundary area formed when a warm air mass contacts and flows over a colder air mass (google a picture) * Slow moving * Warm moist air * Low Ceiling * Poor visibility * light moderarte precipitation * Stratiform clouds * Drizzle * Rise in temp *

Answer 52

VFR: Ceiling greater than 3000 feet and visibility greater than 5 miles (includes sky clear). VFR = \>3000′ and \>5 miles

Answer 53

Marginal VFR (MVFR): Ceilings 1,000 to 3,000 feet and/or visibility is 3-5 miles inclusive. MVFR = 1000-3000′ and/or 3-5 miles

Answer 54

The direction of airflow with respect to an airfoil. It is parallel and opposite the path of the airfoils movement.

Answer 55

* Surface Analysis Charts are computer-generated charts with frontal and pressure analysis issued from the Hydro-meteorological Prediction Center (HPC). Locations of High, Low, Trough, ridges, Fronts, Sea Level Pressure * Issued every 3 hours Valid Time (VT) of the chart on the lower left corresponds to the time of the observations Valid time is given in UTC Information is about 2-3 hours old Information is all observed data

Answer 56

occurs when a fast moving cold front catches up with a slow moving warm front. Warm front prevails but immediately followed by a cold front weather

Answer 57

When the force of two air masses are relatively equal. The boundary or front that separates the remains stationary and influence the local weather for days

Answer 58

* Standard Briefing: Anytime planning a fight & you’ve not received previous brieing * Abbreviated: Info to supplement mass data & update a previous briefing * Outlook: Prposed time of departure is six or more hours from the time of briefing * In Flight Briefing: Update a previous flight briefing

Answer 59

Elongated area of relatively high atmosphere pressure Decending air Dissipation of cloudiness Good weather

Answer 60

Elongated area of low atmosphere pressure rising air Conductive to cloudiness and precipitation hence bad weather

Answer 61

The rate of wind velocity per unit, it occurs * Low Level temperature inversion * Frontal zone or thunderstorm * Clear air turbulance

Answer 62

The actual amount of moisture in the air compared to the total amount of moisture it can hold at that temp EX. Relative humidity at 65%. Means 65% of the moisture the air can hold at that pressure and altitude

Answer 63

Cumulus Unstable Showery precipitation Good visibility

Answer 64

9900 and less than 5 knots when the forecast speed is less than 5 knots, coded group is 9900

Answer 65

* MVFR = Ceilings 1,000-3,000 feet and or 3-5 am visibility * Maintain VFR cloud clearance when in class E * Blue Dot also means minimum

Answer 66

Convective currents (Upward and downward motion) and winds (horizontal motion)

Answer 67

- Surface, upper air, radar, satelite Observations gather data from surface and upper altitude to from the basis of all weather forecasts advisories and briefings

Answer 68

the changing of ice directly to water vapor bypassing the liquid stage

Answer 69

* Thermosphere = 280,000 ft and up * Mesosphere = 160,000 ft - 280,000 ft * Stratosphere = 20,001 - 160,000 ft * Troposphere = sfc - 20,000ft * Tropopause = Traps moisture and weather

Answer 70

78% Nitrogen, 21 % Oxygen, 1% Trace gas

Answer 71

Surface friction Slows the winds and the coriolis effect/pressure gradient force to not be equal since slow winds are less affecte by coriolis

Answer 72

Decreases at a rate of 2 Degrees Celsius per 1000 ft of altitude gain ex 15 degrees = sea level 13 degrees = 1000 ft 11 degrees = 2000 ft 9 degrees = 3000 ft

Answer 73

An AIRMET, or Airmen's Meteorological Information, is a concise description of weather phenomena that are occurring or may occur (forecast) along an air route that may affect aircraft safety. ... NOTE: The definition has changed and no longer says "light aircraft"; AIRMETs are intended for all aircraft. Covers 3,000 plus miles, good for 6 hours 1. Sierra: Mountain Obscuration IFR, ceilings less than 1,000 feet and/or visibility less than 3 sm over 50% 2. Tango: Turbulance, light moderate turbulance, sustained surface winds 30 kts or more 3. Zulu: Icing Light - moderate icing/freezing levels

Answer 74

Watch YouTube

Answer 75

Cirrus = very high Stratus: Flat, formed in layers typically low Cumulus= Stacked on top of one another, puffy, flat base puffy rounded towers

Answer 76

Cool, dense air moving inland over the water

Answer 77

* Cumulus: fluffy low but build up and bring rain * Stratus: long, total cloud cover, can bring rain * Cirrus: high, above 20,000 ft indicate a change in weather is coming

Answer 78

* Derived/Generated from METARS * Includes information on visibility, current weather (rain, snow, fog, etc) sky coverage, and ceiling * Broadly characterizes IFR, MVFR, VFR

Answer 79

* SFC occur on clear, cool nights when the air close to the ground is cooled but he lowering temp of the ground * Frontal inversions occur when warm air spreads over a layer of coooler or cooler air is forced under a layer of warm air

Answer 80

* Increase in 20 degrees F doubles the amount of moisture air can hold * Decrease of 20 degrees F cuts the amount of moisture the air can hold in half

Answer 81

* Location of fronts: location type, speed, direction * Cloud layers: location of clouds base/ceilings, for determining if you can climb above icing layers or decend beneath. * Freeziing levels: Important to avoid icing conditions * Air temperature/Pressure: ice tends to be found in low pressure are at temps at or around freezing

Answer 82

* Dry adiabatic lapse rate is 3degrees C per 1,000 ft * Wet/moist adiabatic lapse rate varies 1.1-2.8 degreesC per 1,000 feet

Answer 83

* Trough: an elongated area of relatively low atmospheric pressure * Ridge: an elongated area of high atmospheric pressure

Answer 84

Low pressure: inward, upward, counter clock High pressure: outward, downward, clockwise

Answer 85

1” mercury per 1,000 feet

Answer 86

Analyzed charts of surface weather observations. The chart depicts the distribuition of several items including sea level pressure, position of highs, lows, ridges, troughs, the location of fronts, and various boundaries such as dry lines, outflow, sea-breeze, fronts, and convergence lines Every three hours, high, low pressure, fronts, temp, DP, wind, speed direction, local weather, and obscurations

Answer 87

* Sigmets * Convective sigmets * Airmets * Cennter weather advisory

Answer 88

* 7545 (always 75) Subtract 100 from speed and add 50 to coded direction * 7799 (always 77) winds 200+ kts are indicated as forecast speed of 199 kts

Answer 89

Radiation (Ground) Fog Advection Fog Upslope Fog Evaporation Fog Ice Fog

Answer 90

Radiation (Ground) Fog: Radiation, also know as ground fog, forms over low-lying flat surfaces on clear, calm, humid nights [Figure 1] Typically extends less than 20' off the ground As the surface cools by radiation, the adjacent air also is cooled to its dew point Cloudy nights reflect terrestrial radiation back to the death reducing cooling through a "blanket" effect would prevent formation Radiation fog actually occurs when the max temperature is reached Winds 5 to 10 knots result in dense fog while just 5 knots is shallow fog Fog will dissipate due to winds greater than 10 knots or solar heating Surface temperature must rise in order for the fog to clear and so thick layers will last longer as it takes longer to heat the ground

Answer 91

Advection Fog: Advection fog occurs when a low layer of warm, moist air moves over a cooler surface [Figure 2] Some wind velocity is required for formation and in fact, the fog becomes thicker and denser as wind speed increases up to about 15 knots Stronger winds lift moisture into low stratus clouds Fog can stay over water for weeks, moving over land late in the day and back over the water the next morning Generally, there are two scenarios which lend to the formation of advection fog: Cold water rising from the depths to the surface cooling the air above it (i.e., the pacific) Tropical air moving over cold ground (i.e., the gulf coast) Solar radiation generally cannot penetrate the thickness to warm the Earth sufficiently and so wind is required to push air from a cold surface to a warm surface, reversing the saturation process Especially due to the high specific heat of water

Answer 92

Upslope Fog: Forms when moist, stable air is forced up a sloping land mass to a level where the air becomes saturated and condensation occurs [Figure 3] Requires wind for formation This type of fog usually forms a good distance from the peak of the hill or mountain and covers a large area Upslope fog occurs in all mountain ranges in North America This usually occurs during the winter months, when cold air behind a cold front drifts westward and encounters the eastward facing slopes of the Rocky Mountains As the cold, moist air rises up the slopes of the mountains, condensation occurs and extensive areas of fog form on the lower slopes of the mountains

Answer 93

Evaporation Fog: This type of fog forms when sufficient water vapor is added to the air by evaporation and the moist air mixes with cooler, relatively drier air There are two common types of evaporation fog: Steam Fog: Steam or, steaming fog, forms when cold air moves over warm water When the cool air mixes with the warm moist air over the water, the moist air cools until its humidity reaches 100% and fog forms This type of fog takes on the appearance of wisps of smoke rising off the surface of the water giving it the nickname "seasmoke" [Figure 4] Frontal Fog: This type of fog forms when warm raindrops evaporate into a cooler drier layer of air near the ground Once enough rain has evaporated into the layer of cool surface, the humidity of this air reaches 100% and fog forms

Answer 94

Ice Fog: Occurs in cold weather when the temperature is much below freezing and water vapor sublimates directly into ice crystals [Figure 5] Conditions for formation are the same as radiation fog except for cold temperature, 25°F and colder Occurs mostly in arctic regions Can be blinding to someone flying into the sun