- Visibility of 10 km or more, and the lowest visibility is not reported(Note 1: In local routine and special reports, visibility refers to the value(s) to be reported in accordance with International Civil Aviation Organization (ICAO) Annexes 3 22.214.171.124 and 126.96.36.199; in METARs and SPECIs, visibility refers to the value(s) to be reported in accordance with ICAO Annex 3 188.8.131.52.)(Note 2: The lowest visibility is reported in accordance with ICAO Annex 3 184.108.40.206.);
- No cloud of operational significance; and
- No weather of significance to aviation as given in ICAO Annexes 3 220.127.116.11, 18.104.22.168, and 22.214.171.124;
ICAO, 2007: Meteorological Service for International Air Navigation. Annex 3 to the Convention on International Civil Aviation. 16th ed., International Civil Aviation Organization, 187 pp. Accessed 18 November 2020. Available at https://www.wmo.int/pages/prog/www/ISS/Meetings/CT-MTDCF-ET-DRC_Geneva2008/Annex3_16ed.pdf.
Term edited 30 December 2020.
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