NOAA declares weak, likely brief La Niña
NOAA said Oct. 9 that La Niña conditions have formed in the central Pacific, but models suggest the event will stay weak and could fade within months. The pattern can tilt U.S. winter toward wetter conditions in the North and drier in the South and typically lowers wind shear that favors Atlantic hurricanes, yet forecasters say this La Niña is probably too late and too weak to significantly boost storm activity this season.
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📌 Key Facts
- NOAA declared La Niña on Oct. 9, 2025 after central Pacific cooling met the ≥0.5°C threshold.
- NOAA’s Michelle L’Heureux: ~75% chance it remains a weak event and may dissipate within a few months.
- Typical U.S. effects: wetter/snowier North, drier South; globally, wetter Indonesia/Australia and drier parts of East Asia.
- Experts Brian McNoldy and Phil Klotzbach say it appears too late/weak to meaningfully increase late-season Atlantic hurricanes; long-range models show little formation in coming weeks.
- 2025 Atlantic hurricane season has been slightly below average so far despite shear conditions that would normally favor more activity.