reporting conditions above the alternate minima were released for Mildura within 30 minutes of the previous report compared to Adelaide. Figure 107: Distribution and cumulative percentage of type meteorological reports by time since previous release at Mildura Airport 2009 to 2013 Figure 108: Distribution and cumulative percentage of SPECI type meteorological reports by time since previous release at Adelaide Airport 2009 to 2013 Appendix C Data validation and assumptions supporting data – 9: Assumed visibility and ceiling in the absence of explicit values for elements in TAF, TTF, METAR and SPECI weather products Applicable Nominal value of Value Weather weather preference Category Element Visibility Ceiling products Visibility METAR, As reported Reported 1 Explicit or cloud TAF, TTF cloud layers data SKC METAR, N/A 9999 TAF, TTF NSC METAR, N/A 4999 Weather TAF, TTF 2 condition flags NCD METAR N/A 4999 CAVOK TAF, 9999 4999 TTF Vertical As reported As reported 3 Explicit visibility CLD:SKY METAR As reported 3 degree and MAY BE or 999 visibility 4 visibility OBSC height sensor anomaly Remarks METAR As reported As reported 5 Explicit section data Average METAR Average of Average of 6 Average between surrounding surrounding reports reports reports Table 10: Number of weather reports by type of visibility value used, 2009 to 2013 Visibility Number of METARs and SPECIs Mildura Adelaide Explicitly reported in body text 14,581 51,895 Flags used: CAVOK (Set to 9999) 35,982 40,035 Sky Obscured: Set to 999 36 0 Visibility explicitly extracted from remarks section (VIS: XXXX) 40,603 251 No estimation - exclude record from analysis (Set visibility to NULL) 1 2
reporting conditions above the alternate minima were released for Mildura within 30 minutes of the previous report compared to Adelaide. Figure 107: Distribution and cumulative percentage of type meteorological reports by time since previous release at Mildura Airport 2009 to 2013 Figure 108: Distribution and cumulative percentage of SPECI type meteorological reports by time since previous release at Adelaide Airport 2009 to 2013 Appendix C – Data validation and assumptions supporting data 9: Assumed visibility and ceiling in the absence of explicit values for elements in TAF, TTF, METAR and SPECI weather products of preference Value Category Weather Element Applicable weather products Nominal value Visibility Ceiling 1 Explicit Visibility or cloud data METAR, TAF, TTF As reported Reported cloud layers 2 Weather condition flags SKC METAR, TAF, TTF N/A 9999 NSC METAR, TAF, TTF N/A 4999 NCD METAR N/A 4999 CAVOK TAF, TTF 9999 4999 3 Explicit Vertical visibility As reported As reported 4 and visibility sensor anomaly CLD:SKY MAY BE OBSC METAR As reported or 999 3 degree visibility height 5 Explicit Remarks section data METAR As reported As reported 6 Average Average between reports METAR Average of surrounding reports Average of surrounding reports Table 10: Number of weather reports by type of visibility value used, 2009 to 2013 Visibility Number of METARs and SPECIs Mildura Adelaide Explicitly reported in body text 14,581 51,895 Flags used: CAVOK (Set to 9999) 35,982 40,035 Sky Obscured: Set to 999 36 0 Visibility explicitly extracted from remarks section (VIS: XXXX) 40,603 251 No estimation - exclude record from analysis (Set visibility to NULL) 1 2
ar-2013-200-final.docx