Garmin GNC 420W Pilots Guide - Page 225

SECTION 11 ADDITIONAL FEATURES Ceiling and Visibility - Flight Rules VFR Marginal VFR IFR Low IFR (green bars) (green bars) (yellow bars) (yellow bars) Table 11-15 Ceiling and Visibility Graphics Ceiling Precipitation Data Age Visibility Station Identifier Figure 11-48 METAR Symbol Winds Wind Vector - The wind vector indicates the direction of the surface wind to the nearest 30˚ increment (e.g. 30˚, 60˚, 90˚, 120˚, etc.). Wind Speed - In general, the sum of the wind barbs (see Table 11-16) is the sustained surface wind speed. Wind Speed (Blank) Short Barb Long Barb Unknown 5 kts 10 kts ≥ 37 kts Table 11-16 Wind Speed Graphics (Blank) G10 (Green) G11+ (Yellow) Gust Offset Gusts are unknown or < 5 kts above sustained wind speed. Wind is gusting 5 - 10 kts more than sustained speed. Wind is gusting 11 kts or more above its sustained speed. Table 11-17 Gust Offset Graphics To interpret wind speed, add the values of each of the wind speed barbs. In Figure 11-49, there are two long barbs (10 knots each) and one short barb (5 knots each). Thus, the total wind speed is 25 knots. Adding the gust offset to this figure gives winds gusting to 36 knots. Thus, the symbol in Figure 11-49 indicates the surface wind at KFRM is coming from a direction of 300° at a speed of 25 knots, gusting to 36 knots or greater. The data age is 11-20 minutes old. Gust Offset Wind Speed Wind Vector Data Age Figure 11-49 Wind Symbol Temperature - Dewpoints The Temperature-Dewpoint Range symbols (Table 11-18) display the difference between the reported temperature and dewpoint. Differences are shown in degrees Fahrenheit. 190-00140-20 Rev. K GNC 420(A) Pilot's Guide and Reference 11-35