El Salvador is characterized by a predominantly tropical savanna climate. This means the weather remains warm throughout the year, with little temperature variation. The defining characteristic of the climate is the pronounced difference in precipitation, which separates the year into distinct wet and dry seasons. The country’s weather cycle is governed by rainfall patterns rather than traditional temperature-based seasons.
The Tropical Seasonal Cycle
The climate cycle is divided into two main periods: verano (dry season) and invierno (wet season). The dry season (verano) extends from November or December through April, offering consistent sunshine and lower humidity. This period results in clear skies and minimal rainfall, making it the most popular time for tourism and outdoor activities.
The wet season (invierno) begins in May and continues through October. This period accounts for approximately 75% of the country’s annual rainfall, transforming the landscape into a vibrant green. The wet season rarely involves continuous, all-day rain.
Rain typically arrives as heavy afternoon or evening downpours, sometimes referred to as temporales. Morning hours are often clear and sunny, allowing for daily activities before the intense rainfall. Humidity increases significantly during this season, making the air feel heavier.
Geographic Influence on Temperature
While annual temperature remains stable, elevation is the primary factor determining local conditions. El Salvador’s varied topography creates three distinct climate zones, each offering a different temperature profile.
Coastal Lowlands
The Coastal Lowlands, including the Pacific plain, are the hottest and most humid region. Average annual temperatures range from 25°C to 29°C (77°F to 84°F), with daytime highs frequently reaching 32°C to 34°C (90°F to 93°F).
Central Plateau and Valleys
Moving inland, the Central Plateau and Valleys, where San Salvador is located, experience more moderate conditions due to higher elevation. This region sees an annual average temperature of about 23°C (73°F). Maximum temperatures typically range between 30°C and 33°C (86°F and 91°F) during the hottest months. Nights are noticeably cooler, with minimum temperatures occasionally dropping to 13°C (55°F) during the dry season.
Mountain Highlands
The Mountain Highlands, encompassing the country’s higher volcanic slopes, are the coolest zone. Annual average temperatures range from 12°C to 23°C (54°F to 73°F). Minimum temperatures sometimes approach the freezing point at the highest peaks.
Notable Weather Phenomena
Beyond the regular seasonal cycle, El Salvador is occasionally affected by more extreme weather events, particularly during the wet season. Tropical depressions and storms, although seldom making direct landfall as hurricanes, generate substantial rainfall and strong winds along the Pacific coast. These events can lead to flooding and landslides, especially in mountainous and low-lying coastal regions.
The El Niño-Southern Oscillation (ENSO) climate pattern also has an irregular influence on the country’s weather. The warm phase, El Niño, often leads to a marked reduction in rainfall and prolonged drought. This decrease in precipitation can be severe, sometimes causing agricultural stress and heat waves.
Conversely, the cool phase, La Niña, typically intensifies the wet season. La Niña events are associated with increased overall rainfall totals and a higher frequency of storm activity. These irregular climate drivers can cause weather patterns that deviate from typical seasonal averages.