1、Dont want to fly into unsafe conditionsDont want to attempt to takeoff or land and realize we cantWhy do we need to know about weather? ATIS Automatic terminal information service Online Aviationweather.gov Flightplanning.navcanada.ca Flight service When you file a flight plan you can get a weather
2、briefing 1-866-WXBRIEF (1-866-992-7433) Flight following ATC will tell you if there is bad weather on your routeWhere can we find weather info? METAR TAF Area forecast AIRMET SIGMET PIREP Significant weather prognostic charts Winds aloft Radar summary chart Surface analysis chartWhat kinds of weathe
3、r products do we have?Observation of current weather conditions Tells what the weather is right nowMade approximately every hourMETARAviation routine weather reportWeather observers (either human or automated) interpretation of weather conditions at a given site and time and contains the following i
4、nformation in this order: Type of report Station identifier Date and time Modifier (as required) Wind Visibility Runway visual range (as required) Weather phenomena Sky conditions Temperature Dew point Altimeter Remarks (as required)KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RM
5、K AO2 METAR Type of reportEither a METAR which is routine or a SPECI which is non-routineSPECI for significant deterioration or improvement of conditions A SPECI will be issued if the wind direction changes by more than 45 in less than 15 minutes and the sustained winds are 10 knots or more througho
6、ut the wind shiftIf it says nothing, its a METAR Station identifierIn Canada, its C plus the 3 letter identifier for the airport KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2 METARDate and time 6 digit group with the letter Z to denote zulu time First 2 digits are the date
7、 followed by the hour and minutesKEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2071454Z111853Z240755ZMETARCoordinated Universal Time (UTC)Converts local time into Greenwich,England timeMETAR1437ZZBAA UTC +8 10:37 pm 2114Z 5:14 am0322Z 11:22 amMETARConvert your local time to
8、military time (24 hour clock)Add or subtract the time conversion to the military timeThe new time is UTCMETARValid timesMake sure the time on the weather product matches the time youll be flyingYou want to go flying at 1100 local time on the 8th. Your city is UTC -6. You choose a METAR that is valid
9、 at 080155. Can you use it?No. Get the new oneMETARYoure flying in New York (UTC -5) on the 11th. You plan to take off at 1500 local. You use a METAR that is valid at 111957. Can you use it? YesYoure flying in Sydney (UTC +10) on the 29th. You plan to take off at 2115 local. You use a METAR that is
10、valid at 290455. Can you use it? No METAR Modifier AUTO states that it was automated with no human observer A01 means an automated station without precipitation discriminator A02 is an automated station with a precipitation discriminator Can detect rain and snow COR identifies the report as a correc
11、ted report to replace an erroneous earlier report KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2METAR WindThe average 2 minute wind direction and speed are reported in a 5 or 6 digit format First 3 digits are where the wind is blowing from in 10 degree increments Last 2 or
12、3 are wind speed KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2 22058KT 31099KT 03022KTMETARWind Calm wind is when wind speed is less than 3 knots 00000KT A gust is a variation in wind speed of 10 knots or more between peaks and lulls Reported by the letter G followed by th
13、e highest reported gust 21014G25KTMETARWind Variable wind If the wind speed is less than 6 knots and the direction is varying its coded as VRB and the wind speed VRB04KT If the wind speed is more than 6 knots and the wind direction is variable by 60 or more it will be written as the extremes in dire
14、ction separated by a V 32012 280V350 21018G30KT 170V240 04011G25KT 010V070METAR Visibility The greatest distance at which objects can be seen and identified through at least 180, which need not be continuous Reported in statute miles When visibility is less than 7sm the restrictor will be reported I
15、f visibility is less than sm it will be denoted as M1/4sm Visibility of 10 sm or greater will be denoted as 10sm KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2METAR Weather phenomena Precipitation Any form of water particles, solid or liquid, that fall from the atmosphere a
16、nd hit the ground There are nine typesRA rainDZ drizzleSN snowSG snow grainsGR hail inch in diameter or largerGS small hailIC ice crystalsUP unknown precipitation Precipitation types can be grouped together but obscurations are listed separatelyRASN BRHZMETARRainRA Liquid water drops that fall in th
17、e same directionMETARDrizzleDZ Very tiny water drops that can look like theyre floating like fog but theyfall to the ground like rainMETARSnowSN Precipitation formed by small ice particlesMETARSnow grainsSG Very small grains of iceMETARHailGS/GR Balls of ice that fall GR is hail of 5mm or more in di
18、ameter GS is smaller than 5mm METARIce crystalsIC Symmetrical pieces of ice Cirrus clouds are made out of thisMETAR Obscurations to visibility Any phenomena, other than precipitation, that reduce horizontal visibility There are eight types FG fog (visibility less than 5/8sm) BR mist (visibility 5/8
19、6sm) FU smoke HZ haze PY spray SA sand DU dust VA volcanic ash KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2METARFogFG Collection of water droplets that are suspended in the airMETARMistBR Collection of water droplets that are suspended in the air Made of the same thing as
20、 fog Difference is how far you canseeMETARSmokeFU METARHaze HZ When dust, sand, pollution, or other particles make visibility poor Generally thought to be in dry air Can be blue or brown in colorMETARSpray PY Water that is carried off of waves or other bodies METARSandSA Very tiny pieces of rock and
21、 other particles like shellMETARDustDU Particles in the air that can contain dirt, human skin, human and animal hair, pollen, ash, pollution, and lots of other materials METARVolcanic ashVA Any material thrown out of a volcano during an eruptionMETAR2SM FU3SM HZ6SM DU5SM PYMETARWeather phenomena Int
22、ensity is shown with most precipitation types + heavy No symbol is moderate -light Intensity depends on the type of obscuration or precipitation For snow its visibility For rain its the amount of splashMETAREstimating Intensity of Rain Light.From scattered drops that, regardless of duration, do not
23、completely wet an exposed surface up to a condition where individual drops are easily seen. Moderate.Individual drops are not clearly identifiable; spray is observable just above pavements and other hard surfaces. Heavy.Rain seemingly falls in sheets; individual drops are not identifiable; heavy spr
24、ay to height of several inches is observed over hard surfaces.METAREstimating Intensity of Ice Pellets Light.Scattered pellets that do not completely cover an exposed surface regardless of duration. Visibility is not affected. Moderate.Slow accumulation on ground. Visibility reduced by ice pellets t
25、o less than 7 statute miles. Heavy.Rapid accumulation on ground. Visibility reduced by ice pellets to less than 3 statute miles.METAREstimating Intensity of Snow or Drizzle (Based on Visibility) Light.Visibility more than1/2statute mile. Moderate.Visibility from more than1/4statute mile to1/2statute
26、 mile. Heavy.Visibility1/4statute mile or less.METARProximity is reported only for weather occurring in the vicinity of the airport and denoted by VC Vicinity refers to 5-10 sm from the point of observation No intensity symbol is shown when VC is reported 111751Z 12008KT 10SM VCRA OVC022 19/14 A3011
27、 RMK AO2 NEVER -VCRAMETAR Weather phenomena Descriptor Further identify weather phenomena and are used with certain types of precipitation and obscurationMI = shallow and further describes fog that has little vertical extent (less than 6 ft)BC = patches and describes fog that has little vertical ext
28、ent and reduces horizontal visibilityDR = low drifting and is used when dust, sand, or snow is raised by the wind to less than 6 ftBL = blowing and is used when dust, sand, or snow and/or spray is raised to a height of 6 ft or moreTS and SH are often used with precip but the intensity only refers to
29、 the precipitation, not the descriptor+TSRA-SHSNMETARThunderstorm TS A combination of thunder and lightning, with or without rainMETARShowers SH Can be rain, snow, or hail Can start and end abruptlyMETARWhat kind of precipitation, intensity and descriptor do we have here?KEWR 081111Z 03010KT 5SM -RA
30、 BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2METARSix other weather phenomena SQ squall, a sudden increase in wind speed of at least 16 knots, with the speed rising to 22 knots ore more and lasting 1 minute DS dust storm FC funnel cloud SS sand storm PO well developed dust or sand whirls +FC tornado
31、or waterspoutMETARSquallSQ Sudden, sharp increase in wind speed, usually associated with thunderstorms, showers, or heavy snowMETARDust stormDS When strong wind blows dust from the surfaceMETARFunnel cloudFC Water droplets and wind that come out of the base of a cloud and rotate very quickly If it t
32、ouches the ground, it becomes a tornadoMETARSand stormSSMETARWell developed dust or sand whirlsPO Spinning column of dust or sandMETARTornado or waterspout+FC Violent, rotating column of air that is in contact with both the ground and a cumulonimbus cloud Waterspout forms over water and under a cumu
33、liform cloudMETAR Sky condition Reported in eighths SKC or CLR 0 FEW 1/8-2/8 SCT 3/8-4/8 BKN 5/8-7/8 OVC 8/8 A layer is clouds or obscuring phenomena when the base is at approximately the same level A ceiling is the height of the lowest broken or overcast layer Height is reported in a 3 digit number
34、 in AGL When more than one layer is reported, theyre given in ascending order of height FEW010 SCT025 BRK060 If a towering cumulus or cumulonimbus is present, they are reported after the height for which their base represents SCT030TCU KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002
35、 RMK AO2METARTemperature/dew point Reported in Celsius in 2 digit form separated by a / 13/09 Temps below zero are preceded by an M If the temp is present but the dew point is missing, the temp is reported followed by a / If the temp is missing, the whole line is omittedKEWR 081111Z 03010KT 5SM -RA
36、BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2METARAltimeter Reported in a 4 digit format preceded by an A A2995 means an altimeter setting of 29.95 inches hg Normal range is 28.00 31.00A3076A2944KEWR 081111Z 03010KT 5SM -RA BR SCT006 BKN015 OVC040 19/18 A3002 RMK AO2METARRemarks Included in all observ
37、ations Except for precipitation, all phenomena within 5sm of the point of observation are reported as at the station Distance remarks are in sm except for lightning which is in nm Direction of phenomena is indicated with the 8 points on the compass N, NE, E, SE, S, SW, W, NW Movement of weather is i
38、ndicated by the direction toward which the phenomena is movingMETARKSEA 081053Z 00000KT 10SM CLR 16/10 A3011 RMK AO2 SLP198 T01560100 $KEWR 081351Z 02010KT 10SM OVC007 20/18 A3005 RMK AO2 CIG 005V009 T02000183KATL 081352Z 33014G19KT 10SM SCT014 BKN180 BKN250 17/13 A2996 RMK AO2 SLP141 T01720128METAR
39、KJFK 111651Z 11008KT 10SM -RA FEW017 OVC026 20/14 A3012 KJFK 111851Z 09008KT 10SM FEW018 OVC022 20/15 A3009 RMK AO2 RAE05 T02000150KTPA 120153Z 33003KT 10SM FEW040 SCT110 SCT250 27/22 A3007 RMK AO2 SLP183 FRQ LTG E-SE CB DSNT E-SE T02670222 $ AO2 RAB49METAR Concise statement of the expected meteorol
40、ogical conditions at an airport during a specified period Scheduled 4 times daily at 0000Z, 0600Z, 1200Z, and 1800Z Use the same codes as METARs and the same order of itemsTAFTime elementsTEMPO, temporary Used for temporary fluctuations in wind, visibility, weather or sky condition that are expected
41、 to last not less than 1 hour and to occur less than half of the time period Followed by a 4 digit group giving the beginning and ending hour of the time period for the temporary conditions 5SM BR BKN 030 TEMPO 1316 2SM BR The visibility will temporarily reduce to 2sm between 1300 and 1600TAFTime el
42、ementsFM, from When a rapid and significant change, usually occurring in less than 1 hour is expected Contains wind, visibility, weather, sky condition and windshear Weather and windshear can be omitted if theyre not significant to aviation FM1600 16010KT P6SM SKC From 1600Z wind will be from 160 at
43、 10 knots, visibility is greater than 6sm and sky will be clearTAFTime elementsBECMG, becoming A gradual change is expected over a longer period of time but not longer than 2 hours 4 digit number showing the start and stop time for the conditions Only the changing conditions are reported in BECMG gr
44、oup BECMG 2224 20013G20KT 4SM SHRA OVC020 Between 2200 and 2400Z conditions will become winds from 200 at 13 knots gusting to 20 knots, 4 sm visibility with rain showers and overcast at 2000 ftTAF Time elements PROB, probabilityIndicates the chance of thunderstorms or other precipitation with associ
45、ated weather conditionsPROB40 means theres a 40-49% chancePROB30 means theres a 30-39% chanceIf the chance is 50% or greater its considered prevailing wind and included in the weather or TEMPO sections4 digit number gives start and stop times PROB40 0006 2SM TSRA OVC008CB Between 0000-0600Z theres a
46、 40-49% chance of 2sm visibility, thunderstorms with moderate rain, ceiling of 800 ft overcast cumulonimbusTAF KIAH 081131Z 0812/0918 VRB02KT P6SM SKC FM081500 01008KT P6SM SKC FM090200 VRB02KT P6SM SKC FM091400 01007KT P6SM SKC KORD 081357Z 0814/0918 01012KT P6SM FEW150 OVC250 FM081500 03013G22KT P
47、6SM SCT120 OVC200 FM081900 03015G25KT P6SM SCT050 BKN080 FM090000 04010G18KT P6SM VCSH FEW025 OVC040 FM090600 04009KT 6SM -SHRA FEW007 SCT015 OVC025 FM091200 04012KT P6SM SCT006 OVC015TAFhttp:/www.navcanada.ca/ContentDefinitionFiles/ Services/AWS/AWS_Guide_EN.pdfFor weather that is potentially hazar
48、dous to all aircraftIssued for the following: active thunderstorm areas lines of thunderstorms heavy hail severe turbulence or icing marked mountain waves hurricanes widespread sand or dust storms volcanic ash low level wind shear tornado or waterspoutSIGMET (WS)Active thunderstorm areaLine of thund
49、erstormsSIGMET (WS)Severe turbulence Turbulence that causes large, abrupt changes in altitude and/or attitude. It usually causes large variations in indicated airspeed. Aircraft may be momentarily out of control Occupants are forced violently against seat belts or shoulder straps. Unsecured objects
50、are tossed about. Food Service and walking are impossible. Severe icing The rate of accumulation is such that deicing/anti-icing equipment fails to reduce or control the hazard. Immediate flight diversion is necessarySIGMET (WS)Marked mountain wavesSIGMET (WS)HurricanesSIGMET (WS)Low level wind shea
