Update #3: The S-NPP VIIRS-DNB-GAIN-RATIOS and VIIRS-DNB-DN0 LUTs have been ingested to IDPS operations at 22:13z today (July 7, 2022). These have addressed the degraded status of the DNB products for S-NPP with all VIIRS products now meeting operational requirements. This will be the final update for this notice. 

Update #2: After analysis by Cal/Val teams, VIIRS reflective and thermal bands (M1-M16 and I1-I5) have returned to their nominal operational status. DNB (Day Night Band) products remain degraded and will be corrected once IDPS has ingested a LUT (Look-up Table) developed based on the DNB calibration activities today. This LUT is expected to be in operations within the next 1-2 weeks. An update will be posted once this LUT is in operations and all VIIRS products have returned to operational status. 

Update #1: As of 16:38:36z (June 28, 2022), engineering was able to successfully execute all commanding activities to restore the S-NPP VIIRS instrument to a nominal state. Please note that while Science and telemetry data may be available from the VIIRS instrument, tuning and product quality checks could take up to two days. Direct Broadcast users should be aware that while this data may be available on HRD, it should not be used operationally until it is verified by the Cal/Val teams. An update will be posted once all verification activities are completed.

Topic:  S-NPP VIIRS Instrument issue during Rev 55272


Date/Time Issued:  July 07, 2022 2318Z


Product(s) or Data Impacted: All S-NPP VIIRS products 


Date/Time of Initial Impact:  June 28, 2022 03:41Z 


Date/Time of expected end Time: June 28, 2022 06:57z


Length of Outage: 3 hours 16 minutes


Details/Specifics of Change:  During Rev 55272 (AOS 04:43:32Z), Operations received multiple VIIRS YH alarms indicating S-NPP VIIRS experienced an anomaly and the instrument entered an anomalous state (single board computer lockup suspected). Engineering has been contacted and is investigating. All science and telemetry data will not be available until the instrument is restored to an operational state. All missed data will not be recoverable. The NOAA-20 VIIRS instrument will continue to provide all the primary VIIRS data needs.