Garmin HTAWS User Guide - Page 19

Part Two: Section 2 XM Weather • Winds Aloft (WINDS). The Winds Aloft selection provides the pilot with wind speed and direction. The winds at a given altitude are selected in the Winds Aloft Alt below the WINDS selection. The selected altitude is shown along with the product time. • Textual Meteorological Aerodrome Reports (METARs). When you zoom in to show the airport symbol associated with the colored flag for a graphical METAR, and move the Map Pointer to highlight that airport, you can then press ENT to see the Textual METAR page for that airport. The Textual METAR page is one of the airport pages of the WPT page group. • Graphical Meteorological Aerodrome Reports (METARs). The XM Weather page (in the NAV page group) can show colored flags to indicate the level of current weather conditions at those airports for which textual METAR reports are available. The flags are color-coded to indicate the severity of the current weather at the airport: cyan for VFR conditions, green for Marginal VFR conditions, yellow for IFR conditions, or magenta of Low IFR conditions. • Terminal Aerodrome Forecast (TAFs). A TAF page is added among the airport pages of the WPT page group. The TAF page differs from the Textual METAR page in that it describes forecast future weather conditions rather than current conditions. • Temporary Flight Restrictions (TFRs). The boundaries of areas with TFRs are outlined in yellow on the Map and XM Weather pages of the NAV page group. In the 500W-series, TFR boundaries are also shown on the NAV main page. You can obtain more information about a TFR by bringing up the map cursor, moving the map cursor to within the yellow outlined area, and pressing the ENT key. Weather Product Age The age of the displayed weather product-or the effective time of Winds Aloft predictions-is shown in the upper right corner of the display. For example, if NEXRAD is displayed, "0:05" indicates that the data are five minutes old. If Winds Aloft predictions are being displayed, "10:00" indicates the effective time for the displayed prediction is 10:00 AM. The data for each XM Weather product are updated regularly from the GDL 69/69A. XM Weather products expire after the following intervals: Product METARs NEXRAD/Radar Coverage TFRs TAFs Lightning SCITs Winds Aloft Predictions Expiration Interval 90 minutes 30 minutes 60 minutes 60 minutes 30 minutes 30 minutes 90 minutes When the age of the displayed XM Weather product reaches one half of its expiration time, the color of the displayed time changes from green to amber. Expired XM Weather products are never displayed. In the unlikely event that the data should expire before a fresh update is received, the time will be dashed out and the data removed from the display. XM NEXRAD Weather The National Weather Service's network of WSR88D Doppler weather surveillance radars-also called NEXRAD, for Next Generation Radar-has greatly improved the detection of meteorological events such as thunderstorms, tornados, and hurricanes. An extensive network of NEXRAD weather radars provides 190-00356-30 Rev H 13