El Niño Update: What Changed While You Were Sweating
In July we wrote about a super El Niño forming in the Pacific and what a wet winter could mean for San Diego food and beverage. One paragraph near the end told readers not to skip past the next three months, because a hot, muggy late summer would arrive well before any storm did, and it would change cold-chain math, walk-in loads, patio comfort, and staff safety.
That was August, and nobody in this county needs to be told it happened.
The forecast has changed since we published, and so has the timeline for the work we recommended.
The heat, by the numbers
A ridge of high pressure parked over the Southwest for most of the second half of August and refused to move. Temperatures ran 5 to 15 degrees above normal for days at a stretch. The National Weather Service had a Heat Advisory on the coast and an Extreme Heat Warning for the inland valleys, mountains, and deserts, extended twice, finally expiring the evening of Friday, August 28. Inland highs ran 95 to 107 and the deserts sat between 110 and 117. Ramona tied its daily record at 102 and was forecast to break it the next day, while Chula Vista, Escondido, Vista, Campo, and Palomar Mountain all flirted with records of their own.
The overnight numbers got less coverage and did more damage. Lows on the coast and inland never dropped out of the 70s. Normally cold water upwells along the coast and cools the air overnight, which is what keeps San Diego summers livable without air conditioning. That process stalled. NWS meteorologist Philip Gonsalves told KPBS the upwelling has been weak or nonexistent.
The water shows it too. Sea surface temperatures off San Diego this month were among the warmest ever observed here for this time of year, and the global average sea surface temperature set an all-time record on August 22, months after oceans normally peak.
Monsoon moisture came along with the heat and added humidity on top of it. That is also why the Tijuana River Valley odor problem got noticeably worse during the worst of it, since higher humidity drives up hydrogen sulfide emissions. South Bay operators know exactly what that week smelled like.
Relief arrived the weekend of August 29 and 30. Coastal highs are back in the upper 70s as of this week.
The forecast: the odds went up, a lot
When we published in July, NOAA put the chance of this El Niño reaching "very strong" at 67 percent. The Climate Prediction Center's August 13 diagnostic discussion raised that to greater than 90 percent for fall and winter 2026–27, with sea surface temperature anomalies in the eastern equatorial Pacific already exceeding +2.0°C. It also added a figure that wasn't on the table before: a 69 percent chance of a historic event during October through December, stronger than any El Niño ever recorded.
The near-term outlook calls for more of what August delivered before anything changes. Predictive Services expects above-normal temperatures across Southern California through September with precipitation near to below normal, then a flip to below-normal temperatures and near-to-above-normal precipitation in October and November. The same outlook expects fewer Santa Ana wind events than usual through those two months.
What the heat cost the food and beverage side
Cold chain took the hit nobody logs. Walk-ins and reach-ins are sized around a nightly recovery period that never came. When ambient temperatures stay above 75 overnight, compressors run continuously for a week and a half, condensers clog faster, and equipment that was already marginal tends to fail on the hottest day rather than a convenient one. Any unit that struggled in August is now a unit running on borrowed time.
Demand moved before it dropped. Beach-adjacent businesses had a strong stretch. Inland patios and midday dayparts did not. The pattern repeats in every California heat event, with coastal operators picking up inland refugees while inland dining rooms go quiet and takeout climbs. If August looked bad in aggregate, split it by daypart and location before drawing conclusions from it.
Energy became a real line item. Sustained triple digits inland means every compressor, HVAC unit, and ice machine in the county pulling at once during peak-price windows. On a time-of-use rate, a heat wave costs more than the extra kilowatt-hours suggest.
Growers are in the worst of it. Avocado trees struggle above 100 degrees and drop fruit once temperatures moderate, so the damage gets counted after the heat ends rather than during. That lands on top of a decade-long contraction. San Diego County has gone from roughly 25,000 acres of avocados to about 14,000, driven mostly by water costs, and Escondido alone lost a quarter of its acreage between 2014 and 2022. Every heat event now hits a grower base that is smaller and thinner-margined than the one before it.
The ocean is a sourcing variable. Water this warm changes what gets caught locally and what comes off the boats. Warm-water species move north, cool-water species move deep or move out, and the local seafood mix in September may not match what your menu assumed in June. Talk to your fish purveyor before printing anything.
What changes about the winter plan
The advice from July holds. Check your flood coverage, diversify produce sourcing away from single-source local supply, weatherproof the revenue model for a compressed outdoor season, and stay close to growers and fishermen. What's changed is the confidence behind it and the amount of runway left.
Three things worth moving up:
Service your refrigeration now. Every operator in the county just ran their equipment at maximum for two weeks. HVAC and refrigeration techs are about to be booked solid. Get in that line before the first storm turns it into an emergency call.
Have the produce conversation in September. Growers know what the heat did to their trees long before it appears in a market price. That conversation costs nothing and it's the earliest signal available.
Assume a short window. Anything that requires dry weather and roof access, including drainage, sealing, patio structures, and awnings, has about four weeks.
The August heat was a preview of the extreme weather that’s possible with a historic El Niño event. We’ll continue to track the weather and, more importantly, its impacts on San Diego’s food and bev scene over the coming months. Stay tuned!
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