Cook Islands
Narrative updated. “Cook Islands flags El Niño weather split as region braces for water and food strain”
SPREP has confirmed El Niño conditions and is urging a coordinated regional response, with Cook Islands representatives highlighting a marked weather split across the Pacific at a regional meeting. Measured data for 9 July–6 October 2026 show rainfall 27% below the 1991–2020 normal and mean temperatures 0.9°C below average, though that window is the climatological dry season when totals are normally under 20 mm, so the real test lies in the coming wet season. Regional reporting warns that El Niño is putting water and food supplies under pressure, and the Polynesian Voyaging Society has already added a year to its Moananuiākea Voyage in response to the updated climate outlook.
165 mm vs 227 mm normal
Measured rainfall for 9 July–6 October 2026 ran 27% below the 1991–2020 normal, though this window falls in the climatological dry season when totals are normally under 20 mm, so the meaningful signal is the outlook for the coming wet season rather than the percentage itself.
News source22.27°C mean vs 23.15°C normal
Mean temperature for the same window came in 0.9°C below normal, a cooler-than-average dry season that sits oddly against the strong El Niño signal and the warming discussed in regional coverage.
The dry-season agricultural calendar (May–October) is proceeding on schedule, but regional reporting warns that El Niño-driven water and food pressure could delay or reduce planting once the wet season (November–April) begins.
NASA POWER (MERRA-2) reanalysis, 9 Jul 2026 – 6 Oct 2026, sampled at the country centroid (-21.2°, -159.8°). Normals are 1991–2020. How this is computed
When it matters
Agricultural calendar for Cook Islands and where the El Niño impact window falls
Last 12 months vs normal
Observed monthly rainfall against the 1991–2020 climatology
Sector by sector
Dry-season planting is on schedule, but El Niño-driven rainfall deficits could cut yields and delay wet-season crops if the coming rains underperform.
Below-normal rainfall and regional warnings of El Niño pressure on water supplies raise the risk of household and agricultural water shortages in the outer islands.
Water scarcity and food-supply pressure could worsen nutrition and increase waterborne disease risk, with cooler-than-normal temperatures limiting heat stress for now.
Reduced rainfall may lower hydropower and rainwater catchment yields, increasing reliance on diesel generation and raising electricity costs.
Shifting El Niño ocean temperatures are expected to alter tuna and coastal fish distribution, potentially disrupting local catches and nearshore food sources.
What happened last time
Past El Niño episodes and how Cook Islands responded. See the full ENSO timeline →
2023-24
El Niño conditions contributed to below-normal rainfall and water security concerns in the Cook Islands, prompting regional monitoring and response coordination.
unsourced background2015-16
Strong El Niño conditions again produced drought stress across the Pacific, with Cook Islands and neighbouring states reporting reduced rainfall and pressure on food and water resources.
unsourced background1997-98
One of the strongest El Niño events on record brought severe drought and water shortages to the Cook Islands and wider South Pacific, straining freshwater supplies on atolls.
unsourced backgroundLatest coverage
RSSPolynesian Voyaging Society adds one year to Moananuiākea Voyage due to updated climate outlook
Pacific Region Update 1: El Niño Monitoring - Regional Summary (As of 22 September 2026)
El Niño Confirmed: Cook Islands Braces for Water and Food Pressure as Region Coordinates Response
SPREP has confirmed El Niño conditions and is urging a coordinated regional response, with Cook Islands representatives highlighting a marked weather split across the Pacific at a regional meeting. Me
El Niño puts water and food supplies in the Pacific under pressure
Cook Islands highlights El Niño weather split at regional meeting
Nearby
Other countries in Polynesia