| - | Light intensity (precip) |
| + | Heavy intensity (precip) |
| $ | Maintenance required (ASOS) |
| = | End of report |
| +FC | Tornado/Water Spout |
| ABT | About |
| ABV | Above |
| AC | Altocumulus |
| ACT | Active, activated |
| AER | Approach end of runway |
| AFD | Airport Facility Directory |
| AIP | Aeronautical Information Publication |
| AIREP | Plain language form of air report |
| AIREP SPECIAL | Air report of special meteorological observation |
| ALQDS | All quadrants |
| ALT | Altitude |
| AMD | Amend, amended |
| AMD | Amended Forecast (TAF) |
| AO1 | Automated Observation without precipitation discriminator (rain/snow) |
| AO2 | Automated Observation with precipitation discriminator (rain/snow) |
| AS | Altostratus |
| ASDA | Accelerate/stop distance available |
| ASDE | Airport Surface Detection Equipment |
| ASSW | Associated with |
| BASE | Cloud base |
| BA | Braking action (FAIR, POOR, NIL) |
| BC | Patches |
| BECMG | Becoming (expected between 2 digit beginning hour and 2 digit ending hour) |
| BINOVC | Breaks in the overcast |
| BKN | Broken (5-7 octas (eighths) cloud coverage) |
| BL | Blowing |
| BLO | Below clouds |
| BLSN | Blowing snow |
| BLW | Below |
| BR | Mist (Fog with vis greater than 5/8 Mile) |
| BRAF | Braking action fair |
| BRAG | Braking action good |
| BRAN | Braking action nil |
| BRAP | Braking action poor |
| BTL | Between layers |
| BTN | Between |
| BYD | Beyond |
| C | Degrees Celsius |
| CAT | Clear Air Turbulence |
| CAVOK | Ceiling And Visibility OK. More than 1500M & 10K (5000 FT/6 SM). No CB, No Precip. |
| CB | Cumulonimbus |
| CC | Cirrocumulus |
| CHINO [LOC] | Cloud Height Indicator at second location not available |
| CI | Cirrus |
| CLD | Clouds |
| CLR | Clear at or below 12,000 feet (ASOS/AWOS report) |
| CMSND | Commissioned |
| CNS | Continuous |
| COR | Correction to the observation |
| COT | Coast |
| CS | Cirrostratus |
| CTN | Caution |
| CU | Cumulus |
| CUF | Cumuliform |
| DCMSND | Decommissioned |
| DEG | Degrees |
| DMO | Dependent Meteorological office |
| DP | Dewpoint |
| DR | Low Drifting |
| DS | Dust Storm |
| DSNT | Distant |
| DTRT | Deteriorate, deteriorating |
| DU | Widespread Dust |
| DUST | Duststorm |
| DZ | Drizzle |
| EXP | Expect(ed), expecting |
| FBL | Light (to qualify icing, turbulence etc) |
| FC | Funnel Cloud |
| FEW | >0-2 octas (eighths) cloud coverage |
| FG | Fog |
| FL | Flight Level |
| FM | From (4 digit beginning time in hours and minutes) |
| FPM | Foot per minute |
| FRONT | Front |
| FRQ | Frequent |
| FT | Feet |
| FU | Smoke |
| FZ | Supercooled/freezing |
| FZDZ | Freezing drizzle |
| FZRA | Freezing rain |
| FZRANO | Freezing rain information not available |
| GND | Ground |
| GR | Hail |
| GRADU | Gradual(ly) |
| GS | Small Hail/Snow Pellets |
| H | High pressure |
| HAIL | Hail |
| HIBAL | High Altitude Balloon |
| HIWAS | Hazardous Inflight Weather Advisory Service |
| HURCN | Hurricane |
| HVY | Heavy |
| HZ | Haze |
| IAO | In and out of clouds |
| IC | Ice Crystals |
| ICE | Icing |
| IFR | Instrument flight rules |
| IMC | Instrument meteorological conditions |
| IMPR | Improve, improving |
| INC | In Clouds |
| INS | Inches |
| INTER | Intermittent |
| INTSF | Intensify(ing) |
| INTST | Intensity |
| JTST | Jet stream |
| KM | Kilometers |
| KMH | Kilometers per hour |
| KT | Knots |
| L | Low pressure area |
| LAN | Land |
| LDA | Landing distance available |
| LDG | Landing |
| LGT | Light |
| LOC | Locally |
| LSQ | Line squall |
| LSR | Loose snow on runway |
| LTG | Lightning |
| LYR | Layer(ed) |
| M | Meters |
| M | Minus or below zero (temperature) |
| M | Less than lowest reportable sensor value (RVR or vis e.g. M1/4SM) |
| MAX | Maximum |
| MB | Millibars |
| MET | Meteorological, meteorology |
| MI | Shallow |
| MIN | Minutes |
| MNM | Minimum |
| MOD | Moderate (icing, turbulence etc.) |
| MOV | Move, moving |
| MPS | Meters per second |
| MS | Minus |
| MSL | Mean sea level |
| MTW | Mountain waves |
| MU | Runway friction coefficent |
| NC | No change |
| NIL | None, nothing |
| NM | Nautical mile(s) |
| NMRS | Numerous |
| NO | Not available (e.g. SLPNO, RVRNO) |
| NOSIG | No significant change |
| NS | Nimbostratus |
| NSC | No significant clouds |
| NSW | No Significant Weather |
| OBS | Observe(d), observation |
| OBSC | Obscure(d), obscuring |
| OCNL | Occasional(ly) |
| OKTA | Eight of sky cover |
| OTP | On top |
| OTS | Out of service |
| OVC | Overcast 8 octas (eighths) cloud coverage |
| P | Greater than highest reportable sensor value (RVR or vis e.g. P6000FT) |
| P6SM | Visibility greater than 6 SM (TAF only) |
| PAEW | Personnel and equipment working |
| PE | Ice Pellets |
| PJE | Parachute Jumping Exercise |
| PK WND | Peak wind |
| PLW | Plow/plowed |
| PNO | Precipitation amount not available |
| PO | Dust/Sand Whirls |
| PPR | Prior permission required |
| PR | Partial |
| PRESFR | Pressure falling rapidly |
| PRESRR | Pressure rising rapidly |
| PROB | Probability |
| PROB30 | Probability 30 percent |
| PS | Plus |
| PSR | Packed snow on runway |
| PWINO | Precipitation identifier sensor not available |
| Pxxxx | In METAR RMK = xx.xx inch (water equivalent) of precipitation in previous hour |
| PY | Spray |
| R | Runway (in RVR measurement) |
| RA | Rain |
| RAB | Rain Began @ HHMM (RAB 1421) or as Min past hour (RAB 21) [METAR] |
| RADAT | Radiosonde observation addl data (RADAT 87045 = 87 % RH at frzg level of 4500 MSL) |
| RAE | Rain Ended @ HHMM (RAE 1433) or as Min past hour (RAE 33) [METAR] |
| RAPID | Rapid(ly) |
| RASN | Rain and snow |
| RCAG | Remote Center Air/Ground Comm Facility |
| RMK | Remark |
| RVR | Runway visual range |
| RVRNO | RVR not available (ASOS) |
| RY/RWY | Runway |
| SA | Sand |
| SAND | Sandstorm |
| SC | Stratocumulus |
| SCSL | Stratocumulus standing lenticular cloud |
| SCT | Scattered 3-4 octas (eighths) cloud coverage |
| SEC | Seconds |
| SEV | Severe (icing, turbulence) |
| SFC | Surface |
| SG | Snow Grains |
| SH | Shower |
| SHWR | Shower |
| SIGMET | Information from MWO concerning certain meteorological phenomena |
| SIR | Snow and ice on runway |
| SKC | Sky Clear |
| SLP | Sea Level Pressure in 3 digit MB (e.g., 1001.3 reported as 013) |
| SLPNO | Sea-level pressure not available |
| SLR | Slush on runway |
| SLW | Slow |
| SM | Statute Miles |
| SMK | Smoke |
| SMO | Supplementary meteorological office |
| SN | Snow |
| SPECI | Special Report |
| SQ | Squall |
| SS | Sandstorm |
| SSR | Secondary Surveillance Radar |
| T | Temperature |
| TAF | Terminal aerodrome forecast in code |
| TAPLEY | Tapley runway friction coefficient |
| TAR | Terminal Area Surveillance Radar |
| TAIL | Tail wind |
| TCH | Threshold Crossing Height |
| TCU | Towering Cumulus |
| TDO | Tornado |
| TDWR | Terminal Doppler Weather Radar |
| TEMPO | Temporary changes expected (between 2 digit beginning hour and 2 digit ending hour) |
| TEND | Trend or tending to |
| TKOF | Takeoff |
| TMPA | Traffic Management Program Alert |
| TODA | Takeoff distance available |
| TOP | Cloud top |
| TORA | Takeoff run available |
| TS | Thunderstorm |
| TSNO | Thunderstorm/lightning detector not available (ASOS) |
| TURB | Turbulence |
| TWY | Taxiway |
| UFN | Until further notice |
| UNL | Unlimited |
| UP | Unknown Precipitation (Automated Observations) |
| UTC | Coordinated Universal Time (=GMT) |
| V | Variable (wind direction and RVR) |
| VA | Volcanic Ash |
| VC | Vicinity. Not at airfield, but within 5-10 SM of center of runway complex. |
| VER | Vertical |
| VFR | Visual flight rules |
| VGSI | Visual Glide Slope Indicator |
| VIS | Visibility |
| VISNO [LOC] | Visibility Indicator at second location not available |
| VMS | Visual meteorological conditions |
| VOLMET | Meteorological information for aircraft in flight |
| VRB | Variable wind direction when speed is less than or equal to 6 knots |
| VRBL | Variable |
| VSP | Vertical speed |
| VV | Vertical Visibility (indefinite ceiling) |
| WAAS | Wide Area Augmentation System |
| WDSPR | Widespread |
| WEF | With effect from |
| WIE | With immediate effect |
| WIP | Work in progress |
| WKN | Weaken(ing) |
| WR | Wet runway |
| WS | Wind shear (In TAFs, low level and not associated with convective activity) |
| WSHFT | Wind shift at (time in minutes after the hour) |
| WSP | Weather Systems Processor |
| WSR | Wet snow on runway |
| WST | Convective Significant Meteorological Information |
| WTSPT | Waterspout |
| WW | Severe Weather Watch Bulletin |
| WX | Weather |