Kingston, the capital of Jamaica, is defined by its Tropical Savanna climate (Köppen Aw). Unlike the lush, rain-drenched north coast, Kingston sits in a unique geographic position that makes it one of the driest and hottest parts of the island.
The Blue Mountain Rain Shadow
Kingston’s weather is fundamentally shaped by the Blue Mountains to the north. As northeast trade winds carry moisture across the island, they hit these peaks, dumping the majority of their rain on the windward side (Portland and St. Mary). By the time the air reaches Kingston, it is significantly drier. This creates a "rain shadow" effect, resulting in Kingston receiving roughly 30-35 inches of rain per year, compared to the 130+ inches seen in other parts of Jamaica.
Seasonal Patterns
Kingston does not have four seasons, but rather a cycle between dry and wet periods:
- The Dry Season (December – April): This is the most popular time for visitors. January and February are the driest months, often seeing less than an inch of rain. Humidity is at its lowest, and skies are consistently clear.
- The First Rainy Peak (May – June): A brief "spring" rainy season occurs, characterized by shorter, intense convectional showers in the afternoons.
- The Mid-Summer Dry Spell (July – August): Despite being in the peak of the hurricane season, July often sees a dip in rainfall. However, temperatures and humidity peak during this time, often pushing heat indices into the high 90s °F (mid-30s °C).
- The Main Rainy Season (September – November): October is historically the wettest month. Rainfall during this time is more frequent and can be associated with tropical waves or depressions.
Diurnal Rhythm (The Daily Cycle)
In Kingston, the weather follows a very predictable daily clock:
- Morning (7 AM – 11 AM): Bright and clear with a gentle land-to-sea breeze. The air feels relatively fresh compared to mid-afternoon.
- Afternoon (12 PM – 4 PM): The temperature peaks, typically reaching between 88°F and 92°F (31°C–33°C). In the wet season, this is when convectional clouds build up over the mountains and may drift over the city to provide a 20-minute "cool-down" downpour.
- Evening (6 PM onwards): As the sun sets, the Doctor’s Breeze (a cooling sea breeze) typically dies down and is replaced by the Undertaker’s Breeze (a cooler land breeze blowing from the mountains toward the sea), which provides natural cooling for the city at night.
Unique Phenomena
- "Northers": Between December and March, cold fronts from the North American mainland can reach Jamaica. While they don't bring "cold" weather to Kingston, they cause a noticeable drop in humidity and