Aviation Meteorological Services TAF, TTF & METAR/SPECI Reference Card

This reference card contains selected TAF , TTF & METAR /SPECI information to help users gain a better understanding of aerodrome forecasts and reports.

TAF (Aerodrome Forecast) is a statement of Sample TAF & TTF METAR meteorological conditions expected for the speci- TAF AMD YPPH 020328Z 0203/0306 fied period of time in the airspace within 5 nauti- 01010KT 9999 -SHRA SCT030 cal miles of the aerodrome reference point. FM020400 25014KT 9999 -SHRA SCT030 METAR (Meteorological Aerodrome Report) FM030300 28020G30KT 9999 -SHRA SCT025 is a routine aerodrome report issued at INTER 0203/0208 25015G25KT 4000 SHRA SCT015 half hourly time intervals. INTER 0208/0212 25015G25KT 6000 SHRA SCT020 INTER 0304/0306 28025G35KT 4000 SHRA BKN015 SPECI (Special Meteorological Report) is a spe- RMK cial aerodrome weather report issued only when T 11 15 15 13 Q 1019 1017 1018 1019 meteorological parameters meet specific criteria. TTF SPECI YPPH 020500Z 27007KT 9999 FEW016 TTF (Trend Forecast) is a three hour trend SCT035 13/11 Q1018 forecast appended to some METAR/SPECI. It RMK RF00.4/006.2 HAZE. supersedes the TAF for its period of validity. INTER 0500/0800 25015G25KT 4000 SHRA SCT015

Elements of TAF, TTF and METAR/SPECI AUTO will be included when a METAR/SPECI eight points of the compass) from the observing contains only automated observations. station, e.g. 8000 2000NE. is given in the format DDDSSKT where DDD Air (and dewpoint temperature in is the mean direction in degrees True rounded to METAR/SPECI) are given in degrees Celsius in the nearest 10 degrees and SS is the mean speed a two-digit group, rounded to the nearest whole in knots (KT). degree. Negative values are preceded by M (minus), e.g. M03. In TAF, air temperature values are The maximum gust will be given after the letter G if preceded by the letter T. In METAR/SPECI, the air it is forecast or observed to exceed the mean by 10 temperature and dewpoint are given knots or more, e.g. 33028G40KT gives a mean wind in the format TT/T T , where T is the air temperature direction of 330 degrees True, with a mean speed of d d and T is the dewpoint temperature, e.g. 22/15. 28 knots and a maximum gust of 40 knots. d QNH is given in hectopascals in a four figure group, At selected aerodromes, an additional wind variation e.g.1008, or 0998. QNH values are preceded by the group may also be included in METAR/SPECI when letter Q. QNH values in METAR/SPECI are rounded the varies by sixty degrees or more down to the whole hectopascal. during the sampling period used for the wind report. For example, 150V220 indicates that the wind has TAF issue time and METAR/SPECI report time varied between 150 and 220. is given in the format DDHHMMZ. For example, 171655Z indicates an issue time of 1655UTC on the is given in metres, in a four-figure group 17th day of the month. (e.g. 0500 = 500m, 2000 = 2000m) with 9999 being used to indicate visibility of 10 kilometres or more. A TAF is normally issued half an hour to two hours prior to the start of the validity period. In METAR/SPECI, two groups may be reported when visibility is not the same in different Validity period for a TAF is given in the format directions; the prevailing visibility first, then the DDHH/DDHH, e.g. 1718/1900 indicates a validity of minimum visibility and its direction (using one of the thirty hours from 1800UTC on the 17th. Weather Information Weather is included in a forecast Did You Know? or report using the abbreviations Prefix Weather Intensity In TAF, the four temperature in the table (left). Examples are: and QNH values are point + Heavy BCFG for patches. forecasts for HH, HH+3, no SHRA for moderate showers Moderate HH+6 and HH+9 where HH prefix of . is the commencement of the – Light Intensity is indicated for TAF validity. Code Weather Descriptor , dust storms, Users should use a linear sandstorms and funnel BC Patches interpolation to determine the (tornados and water spouts), by forecast value between these BL Blowing prefixing the weather groups as points. DR Drifting shown in these examples: DL Distant +TSRA for Information FZ Freezing with heavy rain showers. MI Shallow DZ for moderate . Code Cloud Amount -RA for light rain. PR Partial FEW Few (1 to 2 ) SH Showers SCT Scattered (3 to 4 oktas) Common Abbreviations TS Thunderstorm BKN Broken (5 to 7 oktas) VC in the Vicinity BECMG Becoming OVC Overcast (8 oktas) Code Weather Phenomenon CAVOK Cloud and visibility and NSC Nil Significant cloud BR weather ok NCD Nil cloud detected (in AUTO reports only) DU Dust FM From DS Duststorm INTER Intermittent variations – Cloud amount is forecast or DZ Drizzle periods < 30 mins in a hour reported using the abbreviations FC Funnel cloud MOD Moderate above. FG Fog PROB30 30% chance of forecast Cloud information in TAF and FU Smoke conditions occurring METAR/SPECI is given in the GR order of lowest to highest in PROB40 40% chance of forecast GS Small hail/ pellets accordance with the following conditions occurring HZ Haze rules: RMK (remark) in TAF precedes 1st group is the lowest layer PL pellets information on temperatures and regardless of amount. 2nd group PO Dust devil QNH, and turbulence if forecast is the next layer covering more RA Rain SEV Severe than two eighths of sky. 3rd SA Sand group is the next layer covering TEMPO Temporary variations – more than 4 eighths of sky. SG periods of 30 mins to < 60 mins SN Snow Extra groups - cumulonimbus Z Appended at the end of issue (CB) and towering cumulus (TCU) SQ and validity times to signify UTC when not included in the above. SS Sandstorm (Coordinated Universal Time) Cloud type is not given except for VA Volcanic ash More abbreviations can be found CB and TCU. UP Unidentified precipitation in the AIP Book

The information in this publication is provided for reference only to assist in the interpretation of TAF, TTF METAR/SPECI. Comprehensive educational resources can be found at www.bom.gov.au/aviation/knowledge-centre. For flight planning purposes, users should refer to Airservices Australia’s Aeronautical Information Publications (AIP). © Commonwealth of Australia, 4 November 2019