(2026-08) Bilten chak mwa sou klima ak metyo pou Ayiti, 20 out 2026

FAMINE EARLY WARNING SYSTEMS NETWORK Haiti Monthly Climate and Weather 20 August 2026 Highlights • According to the El Niño Southern Oscillation (ENSO) outlooks, El Niño is strengthening, with a greater than 90% chance of a very strong event during the Northern Hemisphere fall and winter 2026-27. • During July 2026, Haiti experienced below-average conditions. Severe rainfall deficits of 100 mm to 200 mm were observed in most of Artibonite and Centre departments. • In July, northern portions and eastern areas of Haiti observed above-average maximum temperatures, with anomalies ranging from 1°C to 2°C above the mean. Minimum temperatures were near-average in the country. • During September – November 2026 season, the seasonal NMME probabilistic forecast indicate the continuation of below-normal rainfall conditions over Haiti. Moderate probabilities (40–50%) for below-normal rainfall are predicted in most of the country. In terms of temperatures, the NMME forecast indicates high probabilities (60% to more than 70%) above-normal mean temperatures in western regions of Haiti. • For July, the SPI analysis indicates the most severe moisture deficits in Artibonite, northwestern and southwestern Ouest, Nippes, and eastern Grande-Anse departments, as well as most of Sud department, with SPI values ranging from 1.3 to 2 standard deviations below the mean. The SPI forecast suggests that drier-than-average conditions (SPI values ranging from -0.5 to -1.3 standard deviations) will continue in most of Haiti. The FEWS NET Monthly Climate and Weather information bulletin is based on current weather and climate information and monthly and seasonal outlooks from the NOAA CPC. Information on crops, soil moisture, flooding, and evapotranspiration data were produced by FEWS NET, USGS, NASA and USDA. Various sources were used to assess impacts of extreme conditions. Questions or comments about this product may be directed to Dr. Wassila Thiaw, Deputy Director, CPC/NOAA, wassila.thiaw@noaa.gov. Questions about the DOS FEWS NET may be directed to Dr. Kiersten Johnson, Program Manager FEWS NET/DOS, johnsonkb2@state.gov. Haiti seasonal calendar. Source: FEWS NET Current Climate Modes and Teleconnections • • The ENSO outlooks indicate that El Niño strengthened over the past month, with sea surface temperature anomalies exceeding +2.0 °C. Collectively, the coupled oceanatmosphere system reflected a strengthening El Niño. Additionally, El Niño will continue to strengthen through the end of the year (Fig. 1), and there is a 69% chance of a historic event that would exceed the strength of previous El Niño events dating back to 1950 (+2.5 °C or more for a 3-month RONI value) during the October-December 2026 season. For the latest update from the NOAA Climate Prediction Center (CPC) on ENSO, check here. During July 2026, SSTs were warmer than average across the East Pacific, where positive anomalies ranged from 1.0°C to more than 2.5°C. In addition, SSTs in the eastern and western Gulf of America, the northern Caribbean Sea, and the subtropical Atlantic Ocean were above average, with positive anomalies ranging from 0.5°C to 2.0°C. Figure 1. Official ENSO probabilities for the Niño 3.4 relative SST index (5o N−5o S, 170o W−120o W) minus tropical mean (20o N−20o S). Figure updated 13 August 2026. Source: NOAA/CPC • Implications of ENSO conditions: Based on historical records, during El Niño events, drier than average conditions are likely for August to October (ASO) season in most of Haiti (Fig. A1, left panel), while historical El Niño teleconnections indicate warmer than average conditions in eastern and southern portions of Haiti (Fig. A1, right panel). 2 Extreme Events • • Most of Haiti experienced below-average rainfall and above-average temperatures. These conditions have caused a degradation in vegetation, affecting the harvest season in some regions. (Reliefweb, 3 August 2026) There was no report of fire activity in Haiti during July 2026. Rainfall/Precipitation • Climatologically, July is the transition month between the first and the second rainy season of Haiti. During this month, rainfall totals range from 100 mm to 300 mm in central and northern potions of Haiti. Total rainfall values between 25 mm and 100 mm are climatologically observed in the northwestern, portions of northern, and southern Haiti. Past 3 months (May – July 2026): • Totals: Over the three-month period, the largest rainfall totals ranged from 75 mm to 200 mm in eastern Artibonite, Centre, southern Nord, southern Nord-Est, and northern Ouest departments. Southern departments as well as northern departments, including Nord-Ouest, northwestern Artibonite, most of Nord, and most part of Nord-Est, received lower cumulative rainfall totals ranging from 10 mm to 75 mm (Fig. 2a). • Anomalies: Over the last three months, widespread negative precipitation anomalies dominated Haiti. The largest cumulative deficits of 300 mm to 500 mm were concentrated in most of Artibonite, Centre, southern Nord, southern Nord-Est, northern Ouest departments. Elsewhere, negative anomalies from 100 mm to 200 mm were observed (Fig. 2b). Figure 2. Satellite estimates of precipitation (CMORPH) for May – July 2026: (a) 3-month total accumulation and (b) 3-month anomaly. (c) NMME seasonal rainfall probabilistic forecast for September – November 2026. Source: NOAA/NCEP Past 1 Month (July 2026): • Totals: During July 2026, the highest accumulations ranging from 25 mm to 100 mm were concentrated in central and southern portions of Haiti including Artibonite, Centre, Nord, Nord-Est and Ouest departments. On the contrary, the lowest totals of 2 mm to 25 mm 3 dominated northern Haiti as well as Grande-Anse, western Nippes, Sud, southwestern and eastern Sud-Est departments (Fig. 3a). • Anomalies: Haiti experienced below-average conditions in July. Severe rainfall deficits of 100 mm to 200 mm were observed in most of Artibonite and Centre departments. Moderate to substantial rainfall deficits ranging from 10 mm to 100 mm were registered across the rest of the country (Fig. 3b). Figure 3. Satellite estimates of precipitation (CMORPH) for July 2026: (a) 1-month total accumulation and (b) 1-month anomaly. (c) NMME monthly rainfall probabilistic forecast for September 2026. Source: NOAA/NCEP Monthly and Seasonal Forecasts (September 2026 and September – November 2026): • Monthly: The North American Multi-Model Ensemble (NMME) models indicate there is a 40% to 50% likelihood for below-normal rainfall over Haiti during September (Fig. 3c). • Seasonal: The seasonal NMME probabilistic forecast for the September – November 2026 season indicates below-normal rainfall in Haiti. Moderate probabilities (40–50%) for below-normal rainfall are predicted in most of the country. Probabilities for below-normal precipitation between 36% and 40% are expected in northwestern Haiti (Fig. 2c). Temperature Past 3 months (May – July 2026): • Maximums: Seasonal maximum temperatures in northern and eastern regions of Haiti ranged from 30°C to 35°C (not shown). Regarding anomalies, positive anomalies, ranging from 1°C to 2°C above the mean, were observed in central and northern Artibonite, Nord, Nord-Est and Centre departments (Fig. 4a). • Minimums: Seasonal minimum temperatures in most of northern and eastern Haiti were between 20°C to 25°C. Lower values, ranging from 15°C to 20°C, were observed in southeastern regions of Haiti (not shown). The country observed near-average minimum temperatures during May – July season (Fig. 4b). 4 Figure 4. Spatial structure of temperature for May – July 2026: (a) maximum temperature anomaly and (b) minimum temperature anomaly. (c) NMME probabilistic forecast of seasonal 2-m temperature for September – November 2026. Source: NOAA/NCEP Past 1 Month (July 2026): • Maximums: Mean maximum temperatures in northern and eastern regions of Haiti ranged from 30°C to 35°C (not shown). Northern portions and eastern areas of Haiti observed above-average maximum temperatures, with anomalies ranging from 1°C to 2°C above the mean (Fig. 5a). • Minimums: Mean minimum temperatures in northern and eastern portions of Haiti ranged from 20°C to 25°C (not shown). In terms of anomalies, the country experienced nearaverage minimum temperatures during July (Fig. 5b). Figure 5. Spatial structure of temperature for July 2026: (a) maximum temperature anomaly and (b) minimum temperature anomaly. (c) NMME probabilistic forecast of monthly 2-m temperature for September 2026. Source: NOAA/NCEP 5 Monthly and Seasonal Forecasts (September 2026 and September – November 2026): • Monthly: The NMME forecast for September indicates moderate probabilities (50% – 60%) for above-normal mean temperatures in Nord-Ouest, western Nord, and northwestern Artibonite departments. Notably, a higher likelihood (more than 60%) for above-normal conditions is predicted in western portions of Artibonite, northwestern Oueste departments as well as along the coastal regions facing the Canal du Sud in Grande-Anse, Nippes and Sud-Est departments (Fig. 5c). • Seasonal: The seasonal NMME probabilistic forecast for September – November 2026 indicates high probabilities (60% to more than 70%) for above-normal mean temperatures in western regions of Haiti (Fig. 4c). Drought and Dryness The Standardized Precipitation Index (SPI) is used to characterize meteorological drought. SPI compares the precipitation over a specific period of time with the climatology from that same period. Therefore, the SPI values can be thought of as the number of standard deviations the observed anomaly deviates from the climatology. The 1-month SPI values are a good representation of the monthly precipitation anomaly as well as the soil moisture and vegetation health. The 3-month SPI values are a good representation of seasonal precipitation anomalies. The Standardized Precipitation Evapotranspiration Index (SPEI) is similar to the SPI, but it also takes evapotranspiration into account (and therefore the impact of temperatures on water demand). Past 3 Months (May – July 2026): • Dry conditions developed over Haiti during the May – July season due to low rainfall amounts observed during these months. Standardized Precipitation Index (SPI3) values between -0.8 and -1.3 standard deviations were observed in southern Centre, central and eastern Ouest, and eastern Sud-Est departments. Notably, higher moisture deficits with SPI3 values ranging from 1.6 to 2 standard deviations below the mean were registered in most of Haiti (Fig. 6a). Past 1 Month (July 2026): • For July, the SPI analysis indicates the most severe moisture deficits in Artibonite, northwestern and southwestern Ouest, Nippes, and eastern Grande-Anse departments, as well as most of Sud department, with SPI values ranging from 1.3 to 2 standard deviations below the mean. Most of the eastern and southern regions of Haiti negative SPI values ranging from -0.5 to -1.3 standard deviations (Fig. 6b). Current/Forecast (11 August 2026 – 7 September 2026): • The SPI forecast suggests that drier-than-average conditions (SPI values ranging from 0.5 to 1.3 standard deviations below the mean) will continue in most of Haiti. The highest 6 moisture deficits, with SPI values of 1.3 to 1.6 standard deviations below the mean, are expected in southwestern Artibonite and central Gonâve Island (Fig. 6c). Figure 6: Spatial structure of the Standardized Precipitation Index (SPI) for (a) May – July 2026, (b) July 2026, and (c) Spatial structure of SPI constructed from observations for 10 June to 10 August 2026 and 4 weeks forecast ending on 7 September 2026. Source: NOAA/NCEP Water Requirement Satisfaction Index (WRSI) • USGS/EROS crop WRSI: The last WRSI extended product available for the 3rd Dekad of July 2026 indicates mostly ‘Average’ crop conditions in northern Artibonite, Nord, central and southern Nord-Est, Centre, most of southern Ouest, western Nippes, north-central Sud, western and eastern areas of Grande-Anse departments. However, ‘Failure’ to ‘Poor’ crop conditions are indicated in Nord-Est, central-western Artibonite, northern Nord-Est, north-central Ouest departments as well as in other isolated places in southern regions. Elsewhere, WRSI mostly shown ‘Mediocre’’ crop conditions. GEOGLAM Crop Monitor • According to the July 2026 GEOGLAM Global Crop Monitor report, the Maize and rice season are under favorable conditions. The maize harvesting of Printemps season is ongoing, while the harvest of the main-season rice is continuing. Additional Resources - https://protectioncivile.gouv.ht/ - https://www.meteo-haiti.gouv.ht/ 7 Annex Figure A1. ENSO teleconnection for the August – October (ASO) season. El Niño-3.4 composites for precipitation anomaly (mm/day; left panel) and temperature anomaly (°C; right panel), based on MSWEP precipitation and CORe temperature data sets, respectively. Period is 1982-2025. 8