Met Office puts the Pacific 3C above normal, and puts 2027 into next year's budget

The distance between the observation and the forecast is where the work is. NOAA's July reading for the Nino 3.4 region was 1.4 degrees Celsius above normal, with anomalies above 2 degrees in waters farther east ^[7]. The figure drawing attention is the Met Office's: more than 3 degrees above normal in a key equatorial Pacific region late this year, as reported by the BBC on 22 August ^[1][13]. That is at least another 1.6 degrees to be delivered in roughly four months ^[14][15]. The two numbers are not quoted for identical patches of ocean, so the arithmetic is an order of magnitude rather than a gap to track to the decimal.

What keeps it plausible is subsurface. Water in some areas was running as much as 10 degrees above normal below the surface, and if it rises it can strengthen the event over the following months ^[8]. Zeke Hausfather of Berkeley Earth pointed to that stored heat as the factor raising the odds of a record El Nino ^[9]. The mechanism is not exotic: weakening trade winds let warm western Pacific water move east, and the ocean vents heat into the atmosphere ^[4].

Adam Scaife, who runs long-range forecasting at the Met Office, said the signal is stronger than anything he has seen in forecast data ^[3]. Read that precisely. It is a statement about what the models are producing now, measured against a forecast archive, not a measurement of the ocean in December. The comparison against official records since 1950 and against 19th-century reconstructions ^[2] covers 76 years of instrumental record ^[17], which is the reason the claim is interesting and also the reason it has no close analogue to calibrate against.

The calendar is the usable part. El Nino peaks in winter and does most of its work on global average temperature the year after ^[6], which is why Nick Dunstone of the Met Office says there is a very strong chance 2027 beats 2024 as the hottest year on record ^[5]. A record set in 2024 and broken in 2027 has stood three years ^[16]. At that turnover rate the headline ranking tells an operator almost nothing. The regional split does more: elevated drought and wildfire risk in Australia and Indonesia, heavier rain and flooding in Peru, Ecuador and the southern United States ^[10]. Those are opposite hazards requiring separate positions, and they are named a year and a half ahead of the exposure.

The FAO's warning is conditional and should be quoted as such: if drought and flooding damage crop and livestock production, tens of millions of people in vulnerable countries could face severe food shortages ^[11]. Conditional is not the same as speculative when the condition is a forecast this specific.

One caution against extrapolation. The WMO's position is that there is not yet sufficient evidence that climate change increases the frequency or intensity of El Nino, though it accepts that a strong event on a warmer planet can magnify the damage ^[12]. This is a single event with a long lead time, not a new baseline to plan around permanently.