{"id":"AIBD-0752","title":"The National Hurricane Center finds that Google DeepMind's ensemble beat its track forecasts for Hurricane Lorena and foresaw the storm's stall","summary":"NHC found that Google DeepMind's ensemble mean beat its official track forecasts for Hurricane Lorena at all lead times. The model also foresaw that the storm would stall off Baja California.","date_observed":"2025-09-02","date_basis":"event","date_precision":"day","benefit_status":"reported","source_collection":null,"source_entry":null,"account":"Hurricane Lorena, a category 1 storm, stayed just off the Baja California peninsula from 2 to 4 September 2025. Its rain flooded parts of Baja California Sur and swept away three homes, and 119 people sought refuge in shelters. No deaths or injuries could be attributed to Lorena. In its tropical cyclone report of 16 January 2026, NHC found that its official track errors exceeded its five-year averages. Some guidance likely kept Lorena strong for too long and steered it into the peninsula. NHC found that GDMI outperformed the official forecasts at all lead times in a homogeneous comparison. It also found that GDMI correctly predicted that the cyclone would stall off the coast. At 12 to 48 hours, GDMI's track errors were 19.0, 36.1, 53.0 and 47.4 nautical miles. The official errors were 23.3, 46.7, 53.9 and 54.2. The comparison rests on eight forecasts at 12 hours and two at 48 hours. GDMI's intensity forecasts were worse than the official ones at 12 and 24 hours. 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Gibbs. Hurricane Lorena (EP122025), 2–4 September 2025. National Hurricane Center Tropical Cyclone Report, 16 January 2026, p. 5 and Table 4b.","title":"Tropical Cyclone Report: Hurricane Lorena (EP122025)","url":"https://www.nhc.noaa.gov/data/tcr/EP122025_Lorena.pdf","date":"2026-01-16","written_by":"deployer","quote":"The Google DeepMind Ensemble Mean (GDMI) was particularly skillful, outperforming the official forecasts at all forecast intervals, and also correctly predicted the cyclone would stall off the coast of Baja California."},{"kind":"press release","citation":"National Weather Service. AI in Hurricane Forecasting at the National Hurricane Center: A Q&A with NHC's Science Operations Officer. 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The model also foresaw that the storm would stall off Baja California.","account":"Hurricane Lorena, a category 1 storm, stayed just off the Baja California peninsula from 2 to 4 September 2025. Its rain flooded parts of Baja California Sur and swept away three homes, and 119 people sought refuge in shelters. No deaths or injuries could be attributed to Lorena. In its tropical cyclone report of 16 January 2026, NHC found that its official track errors exceeded its five-year averages. Some guidance likely kept Lorena strong for too long and steered it into the peninsula. NHC found that GDMI outperformed the official forecasts at all lead times in a homogeneous comparison. It also found that GDMI correctly predicted that the cyclone would stall off the coast. At 12 to 48 hours, GDMI's track errors were 19.0, 36.1, 53.0 and 47.4 nautical miles. The official errors were 23.3, 46.7, 53.9 and 54.2. The comparison rests on eight forecasts at 12 hours and two at 48 hours. GDMI's intensity forecasts were worse than the official ones at 12 and 24 hours. 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Its rain flooded parts of Baja California Sur and swept away three homes, and 119 people sought refuge in shelters. No deaths or injuries could be attributed to Lorena. In its tropical cyclone report of 16 January 2026, NHC found that its official track errors exceeded its five-year averages. Some guidance likely kept Lorena strong for too long and steered it into the peninsula. NHC found that GDMI outperformed the official forecasts at all lead times in a homogeneous comparison. It also found that GDMI correctly predicted that the cyclone would stall off the coast. At 12 to 48 hours, GDMI's track errors were 19.0, 36.1, 53.0 and 47.4 nautical miles. The official errors were 23.3, 46.7, 53.9 and 54.2. The comparison rests on eight forecasts at 12 hours and two at 48 hours. GDMI's intensity forecasts were worse than the official ones at 12 and 24 hours. The model is experimental guidance that NHC helped Google DeepMind develop.","replication":{"produced_by":["NHC included GDMI among the guidance models in its homogeneous comparison for Lorena.","NHC measured each model's track errors against Lorena's best track."],"must_hold":["The sample is small, with eight forecasts at 12 hours and two at 48 hours.","Forecasters draw on other aids for intensity, since GDMI's intensity forecasts at short range were worse."],"echoes":[]}}},"provenance":{"kind":"legacy_record","basis":"Editorial assignment.","record_fields":["account","replication"],"source_refs":[]},"review_state":"record_mapped","coverage":"partial"}},"summary":{"total":91,"addressed":91,"known":29,"reviewed":2,"reviewed_complete":2,"reviewed_partial":0,"record_mapped":27,"review_not_assessed":62,"not_assessed":0,"complete":false,"by_state":{"value_present":29,"not_reported":0,"unresolved":62,"not_assessed":0,"not_applicable":0,"withheld":0,"source_unavailable":0}}},"presentation_version":"d7149efb43c5d450286cdb0e48df18854f46ad01e727dfd23e6a59b74bf462ec"}