PRIVATE - WEATHER

How do you get a preflight weather briefing?
There are various ways to get a preflight weather briefing which include getting a briefing via telephone (1-800-WX-BRIEF), via frequency (122.0 or 122.2), or through the internet (DUATS.com).

What are the three types of weather briefings and what are they used for?
The three types of weather briefings include an abbreviated briefing, an outlook briefing, and a standard weather briefing. The abbreviated briefing is typically used for flights that are departing within the next hour. An outlook briefing is used for when flights are departing more than six hours from the time of the briefing. And a standard briefing is used when the flight will be departing within one to six hours from the time of the briefing.

How do you get an in-flight weather briefing?
To get an in-flight briefing you can contact a flight service station on the FSS frequency found on your VFR chart.

What is HIWAS?
HIWAS is a weather broadcast over selected VORs, which contains information about AIRMETS, SIGMETS, Convective SIGMETS, and urgent PIREPs.

What kind of weather would change your mind about conducting a flight?
This question doesn't have an exact answer since there are so many variables that go into deciding to make a go/no-go decision such as the pilot's experience level, and the pilot familiarity with the routing, among other factors. Regardless, there are certain weather elements that should/must be avoided at all times. These include flying within 20NM of a thunderstorm, flying when winds exceed the crosswind component of the aircraft, flying into icing conditions without deicing abilities, flying through dust-storms/sand-storms/volcanic ash, flying into clouds without an instrument rating, and flying into severe or greater turbulence.

What is a METAR?
A METAR is an aviation routine report, meaning an hourly weather report for an airport.

What is the difference between ATIS and AWOS/ASOS?
ATIS is an hourly report of airport weather found at controlled airports, whereas AWOS and ASOS are minute-by-minute updated weather typically found at uncontrolled airports.

Interpret the following METAR. 
KLGB 140153Z 02006KT 2SM -RA BR BKN004 OVC018 17/16 A3009 RMK AO2 SLP183
Long Beach Airport, 14th day 0153 Zulu, wind 020 at 6 knots, visibility 2 statute miles, light rain, mist, broken clouds at 400 AGL and overcast at 1,800 AGL, temperature 17 degrees and dew-point 16 degrees, altimeter 30.09, and the remarks are indicating the system can detect precipitation and the sea level pressure is 1018.3hPa.

What do these identifiers indicate HZ, BR, RA, SN, FG, FU, and TS?
Haze, Mist, Rain, Snow, Fog, Smoke, and Thunderstorm.

How do you covert Zulu to local time?
This all depends on what time zone you are located in, but for example if you're in California, you would need to subtract 0700 during the summer and 0800 during the winter from Zulu time.

If the ATIS recording says "...temperature 16, dew point 15..."  What does this mean to you?
A temperature/dew point spread of less than 5° will indicate low visibility. The smaller the temperature/dew point spread, the lower the visibility.

How do you convert Celsius to Fahrenheit?
Multiply Celsius by 1.8 and add 32 to get Fahrenheit.

What’s a special METAR?
A special METAR is non-scheduled METAR that is issued when there is a dramatic change in weather conditions at an airport. The conditions that typically prompt a Special METAR include a change from VFR to IFR or IFR to VFR, or a change in winds which cause a change in the runway(s) in use.

What does it mean if the rotating beacon is on during the day?
This means the airport is reporting less than VFR conditions.

What is special VFR?
Special VFR is a clearance that allows a pilot to operate within controlled airspace with less than VFR weather minimums. The minimum weather requirement for SVFR is 1 mile visibility and you must remain clear of the clouds. Keep in mind that SVFR should not be used when you feel that the flight could be unsafe. SVFR is an option when the weather doesn't meet the minimums, but you are certain that the flight would be safe, for example, flying the pattern when the ceiling is 900 feet.

What are the limitations of SVFR?
In order to get a SVFR clearance you must have at least a private pilot certificate, and if you want to get a SVFR clearance at night you must be instrument rated and the aircraft must be instrument equipped.

Can you get SVFR at LAX?
No, many class B airports prohibit SVFR operations. You can determine whether or not the airport allows this by looking at the airport information section on your VFR chart.

Interpret the following TAF
KLGB 031617Z 0316/0418 09005KT P6SM SCT025 OVC120
TEMPO 0316/0318 -SHRA
FM032100 07007KT 5SM SHRA BR BKN015 OVC030CB
FM041000 15004KT 1/2SM FG OVC005
PROB30 0410/0413 -RA FG OVC003
The TAF is for Long Beach airport, it was issued on the third day at 1617Z, the valid times range from the third day of the month at 1600Z to the fourth day at 1800Z, at 1600Z the winds are 090 at 5 knots, visibility is greater than 6 statute miles, clouds are scattered at 2,500 feet, the ceiling is overcast at 12,000  feet, there are temporary conditions of light rain showers between the 1600Z and 1800Z on the third day of the month, from 2100Z wind is 070 at 7 knots, 5 miles visibility, rain showers, mist, ceiling is broken at 1,500, and a cumulus-nimbus overcast layer is at 3,000 feet, from 1000Z on the fourth day, wind is 150 at 4 knots, visibility is 1/2 a statue mile, fog, overcast at 500 feet, and a 30% probability that between 1000 and 1300Z that there will be light rain, fog, and an overcast ceiling at 300 feet.

How often does a TAF come out?
TAFs are issued 4 times a day, and are typically valid for a 24 hour period.

What is an area forecast?  
An area forecast is issued to provide pilots with general flight conditions for a large area.

Below, determine the valid time and what the weather conditions are expected for KLGB. 
Until 2300Z on the 15th day the conditions are OVC010 with TOPS at 020. At 17Z the sky becomes SCT010. At 21Z the sky becomes SKC. After 23Z until 05Z the next day, the OTLK will be VFR.

San Francisco Area Forecast (FA)
FAUS46 KKCI 151045
FA6W 
SFOC FA 151045
SYNOPSIS AND VFR CLDS/WX
SYNOPSIS VALID UNTIL 160500
CLDS/WX VALID UNTIL 152300...OTLK VALID 152300-160500
WA OR CA AND CSTL WTRS
.
SEE AIRMET SIERRA FOR IFR CONDS AND MTN OBSCN.
TS IMPLY SEV OR GTR TURB SEV ICE LLWS AND IFR CONDS.
NON MSL HGTS DENOTED BY AGL OR CIG.
.
SYNOPSIS...ALF...CLSD LOW W CNTRL NV OPENING AND MOVG TO E CNTRL
NV BY 05Z. WK RDG OVR WRN CA AND ADJ CSTL WTRS BY 05Z.
SFC...QSTNRY FNT NWRN WA INTO W CNTRL OR CSTL WTRS THRU PD.
.
SRN CA..VBG-NID-60NNW BIH LN SWD
CSTL SXNS
  CSTLN LAX NWD...SCT010. TIL 16Z VIS 3-5SM BR. 19Z SKC.
    OTLK...VFR.
  CSTL S OF LAX...OVC010 TOP 020. 17Z SCT010. 21Z SKC.
    OTLK...VFR.
  INLAND...SKC. TIL 16Z VIS 3-5SM BR. OTLK...VFR.
INTR MTNS-DESERTS-VLYS...SKC. OTLK...VFR.
.
CSTL WTRS
WA...SCT CI. OTLK...VFR.
OR...OVC010 TOP 030. OTLK...IFR CIG BR.
CA...
  NRN-CNTRL...OVC010 TOP 030. OTLK...IFR CIG BR.
  SRN
    NRSHORE...SCT010. OTLK...VFR.
    OFFSHORE...OVC010 TOP 020. OTLK...IFR CIG.


How often do area forecasts come out?
Area forecasts are issued three times a day.

What does MVFR represent?
Marginal Visual Flight Rules indicate that visibility is between 3-5 statute miles and the ceiling is between 1,000-3,000 feet.

What type of information is provided by a surface analysis chart?
These charts will show pressure systems and frontal locations.

Describe high and low pressure circulation patterns.
High pressure moves downwards, clockwise, and outwards. Low pressure moves upwards, counter-clockwise, and inwards.

Which pressure system is typically associated with bad/good weather?
Low pressure areas typically indicate area of unfavorable weather. This is due to the gathering of moisture and moving it upwards which can produce atmospheric instability and thunderstorm/cumulus type clouds. The opposite is true for high pressure areas. These high pressure areas push down on the atmosphere which creates a resistance to convective activity.

What are isobars?
Isobars are lines that connect equal pressure

What does is mean when isobars are close together on a prognostic chart?
This indicates a strong pressure gradient, meaning a stronger wind velocity for that area.

What are the characteristics of the different types of fronts?
Cold fronts produce gusty winds, thunderstorm clouds, and poor visibility. Warm fronts produce variable winds, steady light cold rain or snow, and improving visibility. Occluded and stationary fronts will include a combination of the weather found in cold and warm fronts.

Does a cold or warm front move faster, and why?
A cold front moves faster since the air is more dense, thus a more narrow, easier to move, frontal band.


What information is presented on a radar summery chart?
A radar summery chart shows areas of precipitation, the type of precipitation, the height of the precipitation, the speed and direction of the precipitation movement, and the intensity of the precipitation.

Sometimes on radar summary charts you will notice an area that is surrounded by thick black lines. What do these indicate?
These are weather watch areas which indicate areas with forecasted tornadoes and severe thunderstorms.

What information is provided by a winds and temperatures aloft forecast?
Wind velocity and direction, as well as temperatures at specific locations at various altitudes.

In regards to a winds and temperatures aloft forecast, other than winds and temperature, what other type of information can you derive from this forecast?
You can determine the stability of the atmosphere by noting the change in temperature with the increase in altitude. If the decrease is more than 2 degrees per 1,000 feet, the atmosphere is unstable.

How often are winds and temperature forecasts published?
Every 12 hours.

Why are some wind information sections blank?
No wind or temperature information will be given when the altitude is within 1,500 feet of the surface.

Why are some wind information sections missing a temperature?
No temperature information will be given when the altitude is within 2,500 feet of the surface.

What is indicated when the winds aloft forecast shows 9900 and 721001?
9900 indicates the wind is calm. 721001 indicates the wind direction is 220 at 110 knots, with a temperature of 1 degree. To get this answer you must subtract 50 from the first two numbers and add 100 to the next two numbers.

What information can be found on a significant weather prognostic chart?
This is a four panel chart. The top two panels show areas of predicted IFR, MVFR, moderate or greater turbulence, and freezing levels. The bottom panels show pressure systems, fronts, precipitation, and thunderstorms.

How often is the SIG WX PROG chart issued?
Every 6 hours.

What type of weather is shown on a convective outlook chart?
You will find areas of predicted thunderstorms or tornadoes.

What are AIRMETs?
AIRMETs are weather advisories issued to pilots about moderate turbulence, IFR conditions, moderate icing, and mountain obscurations.

What are the three types of AIRMETs?
AIRMET Tango for turbulence, AIRMET Sierra for IFR conditions and mountain obscurations, and AIRMET Zulu for icing.

How often is an AIRMET issued?
Every 6 hours.

What is a SIGMET?
SIGMETs provide information about severe or greater turbulence, severe or greater icing, duststorms, sandstorms, and volcanic ash.

How long are SIGMETs valid for?
For 4 hours.

What is a CONVECTIVE SIGMET?
These inform pilots of large areas of thunderstorms, squall line thunderstorms, and embedded thunderstorms.

What are PIREPS?
These weather reports are made by pilots.

Interpret the following PIREP.
LGB UA /OV LGB120010 /TM 1355 /FL030 /TP C172 /SK OVC030 /TB LGT CHOP OCNL MOD /RM DESCENDING TO RWY 30
The pilot report is for the Long Beach area, the specific location of the report was 10 NM away from the airport on the 120 degree bearing, time was 1355Z, flight level 3,000 feet, type of aircraft a Cessna 172, sky condition is overcast at 3,000, turbulence was light chop and occasionally moderate, remarks were that the pilot was on descent to runway 30.

In a PIREP if you noticed LGB UUA, compared to LGB UA, what would this indicate?
This is an indication that there is some type of urgent weather contained in the PIREP, such as severe turbulence, severe icing, or any other type of information that could be considered hazardous.

What is considered standard temperature and pressure?
15 degrees Celsius and 29.92 inches of mercury are standard.

What is the standard temperature lapse rate?
The standard lapse rate is a loss of 2 degrees per each 1,000 foot increase in altitude.

What are cirrus clouds?
These are high altitude clouds that are made of mostly ice crystals.

What is the difference between stratus and cumulus clouds?
Stratus clouds are very smooth looking clouds that indicate areas of stability, whereas cumulus clouds have a puffy appearance and indicate turbulent conditions.

When a cloud is represented as a nimbus cloud, what does this mean?
Nimbus indicates a rain producing cloud.

How does fog form?
By either cooling the temperature to the dew-point, or by adding moisture to the air, thus raising the dew-point to the temperature.

What are the different types fog?
Radiation, advection, precipitation, and upslope fog are a few.

How does radiation fog form?
After sunset with calm winds, the ground cools at a rapid rate, which then cools the moist air above the ground, and then fog begins to form.

How does advection fog form?
When warm, moist air is pushed over a cooler surface, that air begins to cool, and then fog begins to form.

What is a marine layer?
A marine layer is a form of advection fog that forms near coastal regions.

What is precipitation induced fog?
As rain falls into drier air, it begins to evaporate. During the evaporation process, there is a cooling effect which decreases the temperature to the dew-point.

How does upslope fog form?
As moist air is pushed up terrain, it cools adiabatically.

What 3 elements are needed to form a thunderstorm?
There needs to be a lifting force, an unstable atmosphere, and condensation nuclei (moisture). 

What are the 3 stages of a thunderstorm?
The cumulus (updrafts), mature (up and downdrafts), and dissipating stages (downdrafts).

Can you have lightning without a thunderstorm?
No.

What is hail, and why is it a problem for flying?
Hail is large ice pellets that are created by thunderstorms. Hail can dent the aircraft's outer structure, and possibly shatter cockpit windows.

How far away from a thunderstorm is a safe distance?
When flying near a thunderstorm, you should always be at least 20NM away.

What are microbursts, and how do you handle them?
Microbursts are localized areas of intense downdrafts. You should avoid flying in these areas, but if you do encounter one while landing, you should fly a faster and higher approach.

What is wind shear, and how should you prepare for it during landing?
Wind shear is the sudden change in direction and velocity of wind. The best approach to handling wind shear is to fly at a higher approach speed and fly at an altitude slightly higher than normal. As to how much faster you should fly, you should add half the amount of wind shear to your normal approach speed. For example, if the wind shear is 10 knots and your normal approach speed is 65 knots, your corrected approach speed should be 70 knots.

Do thunderstorms form ahead of cold fronts or warm fronts?
Thunderstorms typically form ahead of cold fronts. This is because the cold air pushes the warm air upwards causing the convective activity needed to form a thunderstorm.

What are squall line thunderstorms?
These are lines of thunderstorms that form ahead of a cold front.

What are embedded thunderstorms?
These are thunderstorms which are obscured by clouds.

How would you be able to determine if there are embedded thunderstorms for your route of flight?
You would need to reference a CONVECTIVE SIGMET, a prognostic chart, or a radar summery chart.

The best course of action to take if you accidentally fly into a cloud is?
First, rely on your flight instruments and not on what your body senses. Second, reverse course by using a standard rate turn. And third, notify ATC of your situation and ask to be radar vectored to an area of VMC.

What is a graveyard spiral?
When an untrained pilot flies into IMC or when flying at night without a visual horizon, the pilot begins to lose the ability to control the aircraft due to the confusion between what the pilot's "feeling" and what the pilot's "seeing" on the flight instruments, and ends up flying a turning descent into the ground.

Why is icing a hazard?
Icing can change the shape of the wing causing a reduction in lift and an increase in drag. Icing also increases weight and decreases thrust.

Discuss the three types of airframe icing, and mention which one is most hazardous.
Three types of airframe icing include clear, rime, and mixed. Clear ice is formed from heavy rain and a collecting surface temperature below freezing. Rime ice is formed from light rain or high levels of moisture, and having a collecting surface below freezing temperature. Mixed icing is a combination of the two. Clear ice is the most hazardous because it deteriorates the shape of the airfoil the most.

What is the solution for icing?
Some common solutions for icing include, activating the aircraft's deicing equipment, descending to a warmer altitude or climbing above the icing conditions, and possibly changing course to a more favorable area. Regardless, whenever encountering icing you should always refer to the aircraft's operating handbook for instructions on how to handle these situations.

Discuss all elements related to carburetor icing.
Carburetor icing is typically caused when flying into high moisture and low temperature environments. The first indication will be a progressive reduction in power (RPM). To counteract carburetor ice, you would apply carburetor heat, add maximum allowable power, and lean the mixture for maximum RPM, but always refer to your POH for exact instructions. After applying carburetor heat you will notice a decrease in RPM followed by a rise in RPM. Remain flying with the carburetor heat out until reaching a more favorable environment.

What is clear air turbulence, and how would you avoid it?
CAT is turbulence you cannot see, such as turbulence not associated thunderstorm. CAT turbulence could be caused from thermals, mountain waves, aircraft wake, or jet streams. To best avoid these areas you would need to check if there are any AIRMETs or SIGMETs for your route of flight.

What is a temperature inversion, and what does that mean for you?
A temperature inversion is an increase in temperature with an increase in altitude. When this happens, a stable environment is produced.

Discuss wake turbulence, and how to avoid it.

Wake turbulence is produced when an object creates lift, the more lift that is created, the stronger the wake turbulence. Wake turbulence spreads outwards from the wing tips and moves downwards, and can last up to 5 minutes. If you can visualize where the wake is, you should have no trouble in avoiding the wake turbulence. Also keep in mind that wake turbulence will move with the direction of wind.