El Niño Guatemala 2026: NOAA Advisory and What It Means for Rain, Drought, and Hurricanes

UPDATE — September 10, 2026: El Niño strengthened again. The September 10 ENSO Diagnostic Discussion holds the El Niño Advisory, puts August’s Niño-3.4 at +1.8°C, Niño-3 at +2.5°C and Niño-1+2 at +3.4°C, with eastern-Pacific SST anomalies now exceeding +3.0°C, and keeps the greater than 90% chance of a very strong event during the Northern Hemisphere fall and winter of 2026-27. The number that moved is the historic-event one: NOAA now puts the chance of an October-December event that “would exceed the strength of previous El Niño events dating back to 1950” at 75%, up from 69% in August, at a three-month RONI value of +2.5°C or more. One index went the other way — Niño-4 fell to +0.1°C in August. The next discussion is October 8, 2026; NOAA publishes on the second Thursday of each month.

For Guatemala, this is the most consequential climate signal of the year. El Niño does not just nudge the weather — it shifts the entire rainy season, the canícula, hurricane risk, hydropower output, and the food security of farmers across the corredor seco.

This post explains what NOAA actually said, what El Niño typically does to Guatemala, and what to watch through 2026-27. It does not predict a specific drought or specific damage. The science does not support that level of specificity. What it does support is a clear picture of risk and a list of things to track.

Quick summary: NOAA has held an El Niño Advisory since June 11, 2026, and its September 10, 2026 discussion has the event strengthening further. August index values: Niño-3.4 +1.8°C, Niño-3 +2.5°C, Niño-1+2 +3.4°C, Niño-4 +0.1°C, with eastern-Pacific SST anomalies exceeding +3.0°C. NOAA gives a greater than 90% chance of a very strong event across the Northern Hemisphere fall and winter, and a 75% chance of a historic October-December event (+2.5°C or more on a three-month RONI value) that would exceed every El Niño back to 1950. For Guatemala this historically means below-average rain in the corredor seco, a longer canícula, fewer Atlantic hurricanes, and pressure on hydropower reservoirs — and in 2026 that is now measured, not forecast: INSIVUMEH told Congress on August 26, 2026 that rainfall is running 29% below normal in the Pacífico and Altiplano Central and 17% below in the Occidente. Figures here are the September 10 NOAA reading; the next discussion is October 8, 2026 (second Thursday of each month).

Explore the data: The Guatemala Weather Hub shows live rainfall accumulation for 22 departments versus the 30-year normal, plus the current ENSO state pulled directly from NOAA. As the season progresses, the hub will show whether the corredor seco and the Pacific lowlands are running wet or dry compared to a normal year — which is the single best leading indicator of El Niño impact on the ground.

What Is El Niño / La Niña?

El Niño and La Niña are the two opposite phases of the El Niño-Southern Oscillation (ENSO) — a natural climate cycle driven by sea-surface temperatures in the central and eastern equatorial Pacific Ocean. Scientists measure it through the Niño-3.4 index, the temperature anomaly in a defined patch of ocean roughly between 5°N-5°S and 170°W-120°W.

• El Niño: Niño-3.4 runs warmer than +0.5°C for an extended period. The warmer ocean shifts atmospheric circulation, weakening trade winds and changing rainfall patterns across the tropics.
• La Niña: The mirror image. Niño-3.4 runs cooler than -0.5°C. Trade winds strengthen. Rainfall patterns shift the opposite way.
• Neutral: Niño-3.4 sits between -0.5°C and +0.5°C. We left this zone in early June 2026 — the index crossed the El Niño threshold, reached +0.7°C by June 11, was +1.4°C for July, and reached +1.8°C for the month of August in NOAA’s September 10 reading.

For Central America, the practical effect of El Niño is that rainfall over the Pacific side of the isthmus tends to decrease, while parts of the Caribbean and South America see different shifts. Guatemala sits right in the zone where El Niño’s drying signal is strongest.

The 2026 Forecast: What NOAA Just Said

The September 10, 2026 ENSO Diagnostic Discussion from NOAA’s Climate Prediction Center is the official basis for everything below. The June, July and August columns are kept so you can see the four-month trajectory — this is moving fast, and every column is the reading NOAA published on that date:

Three things are worth pulling out:

One: The question NOAA is answering has changed. In June the open question was whether this would be a very strong event; from August onward NOAA has treated that as settled at greater than 90% and moved on to a different one — whether October-December produces a historic event, one that “would exceed the strength of previous El Niño events dating back to 1950”. In the September discussion NOAA puts that at 75%, up from 69% in August, and defines it precisely: a three-month RONI value of +2.5°C or more.

Two: Those two probabilities measure different things and must not be read as one trend. June’s 63% and September’s 75% are not the same quantity — 63% was the chance of a very strong event over November-January on the Niño-3.4 index, while 75% is the chance of a historic event over October-December on a three-month RONI value. Read each row on its own: very-strong ran 63% → 81% → greater than 90% → greater than 90%, and the historic-event row ran 69% → 75% across the two discussions that have carried it.

Three: NOAA’s own caveat, carried again in the September text: “With an event of this magnitude, the chances of experiencing impacts consistent with El Niño are larger, though not guaranteed”. (In June the same caveat read: “Even very strong El Niño events do not lead to the expected impact everywhere, but stronger events can more significantly tilt the odds in favor of expected outcomes.”) For Guatemala, the expected outcomes are an extended canícula, corredor seco rainfall deficits, and a suppressed Atlantic hurricane season.

The observational side of the September discussion is just as pointed: sea-surface temperature anomalies exceeding +3.0°C in the eastern equatorial Pacific, subsurface anomalies in excess of +10.0°C at depth against a deeper-than-average thermocline, low-level westerly and upper-level easterly wind anomalies stretching from the western to the east-central equatorial Pacific, enhanced convection from the central to the eastern Pacific with convection suppressed over Indonesia, and both the traditional and the equatorial Southern Oscillation indices still negative. That is a fully coupled ocean-atmosphere signal, not a marginal one.

Source: NOAA Climate Prediction Center, ENSO Diagnostic Discussion, September 10, 2026 (archive copy: enso_disc_sep2026), read at the source on 21 September 2026; prior issues: August 13, 2026, July 9, 2026 and June 11, 2026.

How El Niño Affects Guatemala’s Rainy Season

The typical El Niño signature for Guatemala has been documented across multiple decades. It is not uniform across the country, and it is not uniform across the rainy season.

• Total rainfall: Tends to run below average over most of the country, with the strongest reductions on the Pacific side and in the eastern dry corridor. The western highlands and the Caribbean side are less affected.
• Canícula: The mid-season dry spell (see our canícula guide) often extends and intensifies during El Niño years.
• Onset and end: El Niño rainy seasons can start later than normal and end earlier, compressing the wet window. Farmers who plant on the traditional first-rains signal can lose seed if the rains pause.
• Rainfall intensity: When rain does fall during El Niño years, it sometimes arrives in shorter, more intense bursts — which produces flooding even in a “drier” overall season. Dry soil sheds heavy rain rather than absorbing it.
• Regional differences: The Caribbean lowlands (Izabal) and the western highlands sometimes see near-normal rainfall even when the corredor seco is in severe drought. El Niño is geographically uneven across Guatemala.

The single number that matters most for Guatemala is canícula length. A two-week canícula is normal and even welcome. A six-week canícula in an El Niño year is a humanitarian emergency for subsistence farmers.

What the 2026 season has actually done so far

This is no longer forecast. On August 26, 2026, INSIVUMEH’s director Edwin Rojas and subdirector Mario Mejía briefed the Congress Agriculture, Livestock and Fisheries Commission on observed conditions (INSIVUMEH). What the institute reported:

• Rainfall deficit, national: 29% in the Pacífico and Altiplano Central regions and 17% in the Occidente. Chiquimula, Santa Rosa, Jutiapa and Sololá carry the largest average deficits.
• El Niño probability, August 2026 to March 2027: 95% to 100%.
• August-October outlook: rainfall below the expected climatological values, “especially during the second part of the rainy season” (our translation).
• Temperature: +0.5°C to +1°C above normal across most of the country in August and September, potentially widening to +1°C to +2°C in October.

Coverage of the same session by Infobae (August 27, 2026) reports further figures from the presentation that INSIVUMEH’s own summary does not include — treat these as press-reported: a 33% reduction in first-rainy-season rainfall nationally; a January-June deficit of 29% on the Pacífico, 24% on the Altiplano Central, 17% in the Occidente and over 30% in the Valles de Oriente against the 1991-2020 average; 75% of the 54 days analysed during the canícula in the Valles de Oriente passed without rain; 30-35% lower river flows across all three of the country’s drainage basins; and soil moisture around 20% in the top 30 cm, falling below 10% at depths down to three metres.

Two things that are not in any of those sources, and which this page therefore does not claim: an official 2026 canícula start and end date, and a stated canícula duration. The “54 days” is the analysis window INSIVUMEH used, not a published length.

Historical El Niño Years and What They Did

The following major El Niño events are the reference cases. Each had different intensity and different Guatemala-specific impacts. The strength categories below are NOAA’s official classifications based on the Oceanic Niño Index (ONI).

The pattern to notice: Strong El Niños tend to produce real humanitarian impact in Guatemala. Weak ones often pass with limited damage. The 2014-16 event is the most relevant recent benchmark because it was strong, it persisted, and its effects are still being studied in food-security data published by FAO, the World Food Programme, and the Famine Early Warning Systems Network (FEWS NET).

Source for 2014-16 impact: UN OCHA, Central America Dry Corridor situation reports, 2016 and FEWS NET Guatemala food security reports.

El Niño and Hurricane Season

This is the upside for Guatemala. El Niño years suppress Atlantic hurricane activity through a well-understood mechanism: warmer Pacific water increases upper-level westerly winds over the Caribbean and Atlantic, which produces vertical wind shear. Wind shear tears apart developing tropical storms before they can organize.

NOAA’s seasonal hurricane outlooks consistently forecast below-normal Atlantic hurricane seasons when El Niño is active. For Guatemala this matters in three specific ways:

• Fewer Caribbean-side rainfall surges. Tropical-storm remnants moving across the Caribbean into Izabal and Alta Verapaz are less common in El Niño years.
• Lower probability of major flood disasters. Events like Hurricane Stan (2005, neutral year) and the Eta-Iota double-strike (2020, La Niña year) tend to occur when ENSO is neutral or La Niña, not during El Niño.
• Pacific hurricane season can be more active. NOAA Climate.gov says El Niño favors stronger hurricane activity in the central and eastern Pacific basins.

The trade-off is real: less risk of a single catastrophic flood event, more risk of a slow-grinding drought. Neither is automatically better than the other. They produce different humanitarian and economic consequences.

Source: NOAA, ENSO and Atlantic Hurricane Activity.

What to Watch Through 2026-27

The forecast is not a fixed schedule. It is a probability distribution that updates monthly. Here is the calendar of what matters:

• June 11, 2026: Happened — and it delivered. NOAA declared the El Niño Advisory: Niño-3.4 crossed +0.5°C (to +0.7°C), the atmosphere coupled, and the strength forecast jumped to 63% very strong.

• July 9, 2026: Happened. Niño-3.4 rose to +1.2°C, the very-strong probability climbed to 81% and the window moved to October-December, and NOAA added a 97% chance the event persists through early spring 2027.

• August 13, 2026: Happened — and it escalated the question. Niño-3.4 at +1.4°C for July, very-strong probability above 90%, and a new 69% probability of a historic October-December event exceeding every El Niño since 1950.

• July-August 2026: The canícula window has closed. It was the first on-the-ground test with El Niño actually present, and the result is in the section above: rainfall running 29% below normal on the Pacific side and the central highlands, and — press-reported from INSIVUMEH’s Congress briefing — 75% of the 54 canícula days analysed in the Valles de Oriente with no rain at all. INSIVUMEH has not published a formal canícula retrospective with start and end dates.

• September 10, 2026: Happened — both questions answered the same way: yes. The historic-event probability for October-December rose from 69% to 75%, and Niño-3.4 climbed past +1.4°C to +1.8°C for August, with Niño-1+2 at +3.4°C and eastern-Pacific SST anomalies exceeding +3.0°C. Niño-4 was the single index that fell, to +0.1°C.

• October 8, 2026: Next NOAA ENSO Diagnostic Discussion, and the last one issued before the October-December historic-event window is half over. Watch whether the 75% holds and whether Niño-3.4 keeps climbing past +1.8°C.

• September 2026: Peak rainy-season month, and the last chance for the second half of the wet season to close the gap. INSIVUMEH’s director told Congress it will not — second-season convective rain, however torrential, “will not compensate the deficit accumulated since the start of the season” (our translation of his Spanish).

• October-December 2026: NOAA’s historic-event window — the 75% figure is for this season specifically, measured as a three-month RONI value of +2.5°C or more.

• November 2026-January 2027: The window NOAA used in June for its very-strong forecast, and still inside the “fall and winter” span the August discussion gives a greater than 90% chance of a very strong event.

• Dry season 2026-27: El Niño dry seasons tend to be drier and longer than normal. Reservoir levels, dust, and air quality all get worse.

• April-June 2027: The most economically dangerous window. The 2025-26 corn harvest already happened before El Niño peaked, but the 2026-27 planting cycle will face whatever residual dryness El Niño leaves behind. The corredor seco’s “first hunger season” lands here in bad El Niño years.

The site’s Weather Hub pulls fresh ENSO state from NOAA and, when that source is available, daily rainfall from Visual Crossing, so the actual data — not predictions — is visible as the season unfolds.

Practical Implications

Agriculture

For corredor seco subsistence farmers (Zacapa, Chiquimula, Jutiapa, El Progreso), an extended canícula is the single biggest risk. The first corn harvest (primera) is the most vulnerable. Recommended mitigations historically promoted by FAO and Guatemala’s MAGA include drought-tolerant seed varieties, water-harvesting infrastructure, and staggered planting dates. Coffee is less immediately at risk in the first year of El Niño but is affected by cumulative dry-season dryness in highland production regions like Huehuetenango and San Marcos.

Water Supply

Guatemala City and Antigua draw water from a mix of groundwater, springs, and reservoirs. Dry-season water rationing is already common in normal years. Households on rooftop-tank supply (most of Guatemala City) should expect more frequent municipal shutoffs in early 2027 if El Niño peaks at moderate strength or above.

Hydroelectric Power

Reservoir levels at Chixoy and other major dams are sensitive to multi-month rainfall deficits, and 2026 shows it in the grid’s own numbers. In August 2026 — a rainy-season month — hydropower supplied only 24.5% of Guatemala’s generation, behind coal at 33.2%, and hydro output was 25.5% (110.20 GWh) lower than in August 2025; bunker (fuel-oil) generation rose 151.6% over the same comparison (the wholesale-market operator’s August 2026 market analysis, published September 18, 2026).

Update — September 22, 2026: an energy-emergency alert, not a declaration. Energy and Mines Minister Erwin Barrios said the ministry (MEM) received a note from the Administrador del Mercado Mayorista (AMM), the body that operates Guatemala’s power system, about the possibility of declaring an estado de emergencia energética. The official Diario de Centro América gives the cause as the “Super Niño”, which joined two dry seasons into a severe drought that “significantly reduced hydroelectric generation and affected the Chixoy reservoir” (our translation). As of September 22 no emergency had been declared: Prensa Libre reported that the minister was analyzing whether one is warranted. According to the Diario de Centro América, the measure would speed up the entry of other generators to cover demand and ensure that costs are recognized. Meanwhile thermal plants, other technologies and imports over the interconnection with Mexico and the region have been covering the hydro shortfall.

On electricity bills, Barrios said a declaration would have little or no impact on the tariff paid by regulated users, because distributors must hold long-term contracts (currently 15 years or more): “We hope little to nothing is passed on to the user, depending on what the market reality is” (Publinews, our translation). The CNEE’s current quarterly tariffs run from August 1 to October 31, 2026; they held EEGSA and DEORSA unchanged and cut DEOCSA by 0.5% (CNEE communiqué, July 31, 2026).

The 2024 precedent. In March 2024, also because of El Niño, the MEM moved to declare an emergency in the national interconnected grid (SNI). Prensa Libre reported on March 18, 2024 that it would take effect on the day the ministerial agreement was published in the Diario de Centro América (expected that day) and would last until May 31, 2024, extendable if the dry conditions persisted. The AMM had requested it at the end of February 2024, and the AMM’s manager said hydro generation that February was 17% below the historical average.

What to watch: whether the MEM publishes an acuerdo declaring the emergency in the Diario de Centro América (in 2024 the emergency was set to take effect on that publication), and the CNEE’s tariffs for the quarter that starts November 1, 2026. Our power outages guide covers the distributor side.

Insurance and Planning

ENSO state is the single best leading indicator for what kind of disaster year is coming. If you are planning major outdoor construction, travel, agricultural investment, or food-supply contracts for 2026-27, the probability distribution above is the correct starting point.

Tourism

Tourism is the least affected sector. El Niño tends to mean fewer “rainy day washout” travel impacts — the rainy-season pattern of clear mornings and afternoon showers usually holds, just with slightly fewer afternoon showers and a longer canícula. For travelers, El Niño rainy seasons can actually be slightly better. The trade-off is that the dry season immediately after tends to be hotter and dustier than normal.

Related Reading

• Guatemala Rainy Season 2026 — month-by-month rainy season guide, daily rain pattern, regional differences.
• Canícula 2026 in Guatemala — the mid-season dry spell, when it hits, and how El Niño can stretch it from 2 weeks to 6.
• Drought in Guatemala 2026 — the El Niño drought risk, where it bites hardest, and the metrics to watch through the canícula.
• Guatemala’s Corredor Seco — the semi-arid dry corridor that becomes the country’s most drought-vulnerable region in El Niño years.
• Corn and Bean Prices 2026 — how drought feeds through to the price of Guatemala’s two staple grains.
• Hurricane Season Guatemala 2026 — Atlantic vs Pacific seasons, suppression mechanism, historical impact comparison.
• Guatemala Weather Hub — live ENSO state, rainfall accumulation vs 30-year normal, 22-department forecast.
• Safety Data — regional flood, landslide, and drought risk by department.

Where to Track 2026 El Niño in Real Time

• NOAA Climate Prediction Center ENSO page — the official source. Updated monthly on the second Thursday.
• INSIVUMEH — Guatemala’s national meteorological institute. Issues seasonal forecasts that incorporate ENSO state, and daily weather alerts.
• FEWS NET Guatemala — food security outlooks for the corredor seco. The first place humanitarian impacts show up in data.
• Guatemala Weather Hub — live ENSO state pulled from NOAA, rainfall accumulation for 22 departments.
• Guatemala coffee price — the ICE “C” contract and the ICO Other Milds indicator. The ICO’s own August 2026 market report attributed that month’s mid-month coffee rally to expectations of a strong El Niño on top of historically low certified Arabica stocks, so this is where ENSO shows up as a price.

El Niño is here, it is strengthening, and as of the September 10 discussion NOAA gives it a greater than 90% chance of finishing the year very strong — with a 75% chance that October-December sets a record going back to 1950. Those are probabilities, not certainties, and NOAA is explicit that even an event of this magnitude does not guarantee the expected impacts everywhere. But the first ground-truth signal for Guatemala has already arrived: the canícula window closed with rainfall running roughly a third below normal in the worst-hit regions, and INSIVUMEH is telling Congress the second half of the rainy season will not make it up. The next forecast refinement lands October 8, 2026. The right posture is informed attention — not alarm, not dismissal.