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8. Weather Phenomena. the Weather As Reported in the METAR Code

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8. Weather Phenomena. the Weather As Reported in the METAR Code 6/17/21 AIM 8. Weather Phenomena. The weather as (e) Obstructions to visibility. There are reported in the METAR code represents a significant eight types of obscuration phenomena in the METAR change in the way weather is currently reported. In code (obscurations are any phenomena in the METAR, weather is reported in the format: atmosphere, other than precipitation, that reduce horizontal visibility): Intensity/Proximity/Descriptor/Precipitation/Ob- FG .......... fog (vsby less than 5/ mile) struction to visibility/Other 8 HZ .......... haze NOTE− FU .......... smoke The “/” above and in the following descriptions (except as PY .......... spray the separator between the temperature and dew point) are BR .......... mist (vsby 5/ − 6 miles) for separation purposes in this publication and do not 8 SA appear in the actual METARs. .......... sand DU .......... dust (a) Intensity applies only to the first type of VA .......... volcanic ash precipitation reported. A “−” denotes light, no symbol denotes moderate, and a “+” denotes heavy. NOTE− Fog (FG) is observed or forecast only when the visibility is (b) Proximity applies to and reported only less than five−eighths of mile, otherwise mist (BR) is for weather occurring in the vicinity of the airport observed or forecast. (between 5 and 10 miles of the point(s) of observation). It is denoted by the letters “VC.” (f) Other. There are five categories of other (Intensity and “VC” will not appear together in the weather phenomena which are reported when they weather group). occur: SQ ........... squall (c) Descriptor. These eight descriptors ap- SS ........... sandstorm ply to the precipitation or obstructions to visibility: DS ........... duststorm TS ........... thunderstorm PO .......... dust/sand whirls DR ........... low drifting FC ........... funnel cloud SH ........... showers +FC ......... tornado/waterspout MI ........... shallow FZ ........... freezing Examples: BC ........... patches BL ........... blowing TSRA ......... thunderstorm with moderate PR ........... partial rain +SN .......... heavy snow NOTE− −RA FG ....... light rain and fog Although “TS” and “SH” are used with precipitation and BRHZ ........ mist and haze may be preceded with an intensity symbol, the intensity still 5 applies to the precipitation, not the descriptor. (visibility /8 mile or greater) FZDZ ......... freezing drizzle (d) Precipitation. There are nine types of VCSH ........ rain shower in the vicinity precipitation in the METAR code: +SHRASNPL .. heavy rain showers, snow, RA .......... rain ice pellets (intensity DZ .......... drizzle indicator refers to the SN .......... snow predominant rain) 1 GR .......... hail ( /4” or greater) GS .......... small hail/snow pellets 9. Sky Condition. The sky condition as PL .......... ice pellets reported in METAR represents a significant change SG .......... snow grains from the way sky condition is currently reported. In IC ........... ice crystals (diamond dust) METAR, sky condition is reported in the format: UP .......... unknown precipitation (automated stations only) Amount/Height/(Type) or Indefinite Ceiling/Height Meteorology 7−1−63 .
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