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IR satellite limits

You've heard the old saying that a picture speaks a thousand words? Well, it might, but it also may trigger a thousand questions. For example, if you look at the observed ceilings based on the latest METARs (EZDeparture Advisor must be moved all the way to the left to see observations), you'll notice many stations reporting MVFR, IFR and LIFR ceilings. But to the northwest, there are no ceiling reports at all. What's going on? Missing data? App dropped the ball?

Actually, this ceiling layer shown above on the EZMap in EZWxBrief only adds a marker to the map if there's a ceiling being reported (or forecast). If the sky cover is reported (or forecast) as clear (or clear below 12,000 feet), scattered or few, then no marker is placed on the map since this does not constitute a ceiling. Ceilings can only be reported for a sky coverage of broken, overcast or an indefinite ceiling (vertical visibility). So this leaves a huge void of markers in the northwestern section of this area (on purpose).

Apps such as Garmin Pilot may also at times provide some confusing imagery. Above is the Internet IR color-enhanced IR satellite image also with a ceiling marker overlay that is valid around the same time as the EZMap display in EZWxBrief. At first glance it would appear that there are some very obvious inconsistencies. Where you see the color contours, the satellite depiction is suggesting there are clouds. Areas without contours should be clear?