Update #2: Critical Weather Day has been updated to start on Sunday, June 1, 2025 at 1000Z  due to geomagnetic storm category G4 earlier than expected.

Update #1: Critical Weather Day has been updated to start on Sunday, June 1, 2025 at 1200Z  due to the earlier onset of geomagnetic storm activity. 

Topic: Critical Weather Day Has Been Declared

Date/Time Issued: May 31, 2025 2030Z

Product(s) or Data Impacted: NWS IT Enterprise

Date/Time Initial Impact: June 01, 2025  1800Z J/DAY 152

Date/Time Expected End: June 03, 2025 1800 J/DAYZ 154

Length of Event: 30 Hours

Requester: NCEP, NCF

Details/Specifics: Geomagnetic Storm Category G4 or greater predicted.

Pause all operational changes. Request Regional or Center management approval prior to moving forward with any operational change. Managers should consider the critical resources outlined in the NWS IT Playbooks prior to authorizing any operational system, data, or application changes. Please visit the CWD status page for more information:

https://www.nco.ncep.noaa.gov/status/cwd/

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