Mode 4 Testing for both GOES-16 and GOES-17
GOES-17 Data shown in this post are preliminary and non-operational.
Continuous Full Disk (Mode 4) Testing is occurring on October 1 2018. Mode 4 is the highest data flow rate for the ABI and results in a Full Disk image every 5 minutes. No mesoscale sectors are produced during Mode 4 operations. Five-minute CONUS imagery can be produced by subsecting the 5-minute Full-Disk Imagery. This testing started at 0000 UTC on 1 October and will end at 0000 UTC on 2 October.
The animation above shows GOES-17 Full-Disk imagery for the upper-level water vapor imagery (6.19 µm) with a 5-minute cadence. The GOES-16 animation for the same time and location is below.
Careful inspection of the imagery from the two satellites might reveal differences in brightness temperatures between the two instruments. This difference is due to view-angle differences. When the satellite is scanning near the limb, computed brightness temperatures will be cooler because more information detected by the satellite comes from the upper part of the atmosphere. Compare, for example, brightness temperatures just west of former Pacific Hurricane Rosa just west of Baja California. GOES-17, at 89.5 W Longitude, sees warmer temperatures than GOES-16 at 75.2 W Longitude. GOES-16’s view is more oblique, and is through more of the colder upper atmosphere.
(Update: GOES-16 returned to Mode-3 scanning at 1549 UTC on 1 October. Continuous Full Disk scanning on GOES-16 lead to degradation of derived products).