Update #2:  Infrared Atmospheric Sounding Interferometer (IASI) retrievals for the Metop-C Hyper-Spectral Enterprise Algorithm Package (HEAP) are scheduled to resume at 1600 UTC on May 15, 2026. Please note that channels 4 and 8 will continue to be inactive at this time.

Update #1: Due to the ongoing AMSU-A channel 4 problem, Metop-C HEAP IASI retrievals are no longer suitable for operational use. Consequently, the HEAP_IASI_EDR will be disabled at 1430 UTC on April 7, 2026, while the science team works to resolve the issue.

Topic: Metop-C HEAP IASI Retrieval degradation

Date/Time Issued: May 15, 2026 1518 UTC

Product or Data Impacted: Metop-C HEAP IASI Temperature/Moisture Profiles and Trace gases (PDA Shortname - HEAP_IASI_EDR)

Date/Time of Initial Impact: Mar 17, 2026 0100Z

Date/Time of Expected End: TBD

Length of the Outage/Event:  TBD

Details/Specifics : Metop-C HEAP IASI temperature/moisture and trace gas retrievals have failed quality check potentially due to AMSU-A channel 4 noise level reached to a certain level that the number of good retrievals algorithm can make has significantly dropped. The science team has been contacted. A resolution is yet to be determined.

Metop-C HEAP IASI OLR is not affected.

Contact Information for Further Information and Feedback: 

SPSD User Services (spsd.userservices@noaa.gov) and HEAP Product Area Lead (Shuang.Qiu@noaa.gov) 

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