Jeddah Weather Guide: Red Sea Humidity & Desert Heat

Jeddah, known as the "Bride of the Red Sea," occupies a unique geographical position where the vast Arabian Desert meets the deep blue of the Red Sea. This placement creates a climate characterized by intense heat, staggering humidity, and a lifestyle dictated by the sun’s daily cycle.

Typical Weather Patterns

Jeddah experiences a hot desert climate (Köppen BWh), but unlike the bone-dry heat of Riyadh in the interior, Jeddah is defined by its relationship with the water. The sea acts as a massive thermal regulator, preventing temperatures from dropping significantly at night but also infusing the air with relentless moisture. Sunshine is nearly constant, with the city averaging over 3,500 hours of sun annually.

Seasonal Trends

The Scorching Summer (May to September)

Summer in Jeddah is an endurance test of heat and humidity. Daytime temperatures regularly exceed 40°C (104°F), while the "RealFeel" or heat index can soar toward 50°C (122°F) due to humidity levels that frequently hover between 60% and 80%.

• The Coastal Fog: High humidity often creates a heat haze during the day and a warm, low-lying fog at night, reducing visibility and making the air feel thick and heavy.
• Sea Breezes: In the late afternoon, a moderate northwesterly sea breeze often kicks in, providing the only natural relief from the oppressive inland heat.

The Mild Winter (December to February)

This is the most celebrated time of year in Jeddah. Daytime highs settle into a pleasant 25°C to 28°C (77°F to 82°F). Nights are cool and refreshing, occasionally dipping to 15°C (59°F), particularly when cold air masses blow down from the north.

The Transition Months (March–April and October–November)

These "shoulder seasons" are short and unpredictable. Temperatures climb quickly in the spring and descend slowly in the autumn. Most of Jeddah’s rare rainfall occurs during these windows, often in the form of sudden, intense thunderstorms.

The Daily Rhythm

In Jeddah, the climate dictates the clock. During the hotter months, the city effectively "sleeps" during the day. Locals adapt by moving their social lives to the nighttime.

• Morning (6 AM - 10 AM): A brief window for outdoor activity before the sun takes full command.
• Midday (11 AM - 5 PM): The streets empty as most residents seek the "blessed AC" of homes and malls.
• Evening (7 PM - Late): As the sun sets, the city comes alive. The Corniche (waterfront) fills with families enjoying the sea breeze, and shopping districts stay vibrant well past midnight.

Weather Phenomena and Historical Context

• Flash Floods: While it rarely rains, when it does, it is often catastrophic. Jeddah sits at the base of the Sarawat Mountains; intense rain in the highlands drains through "wadis" (dry riverbeds) directly toward the city. The 2009 and 2011 floods remain etched in local memory as historical markers of the desert’s power.
• Dust Storms: Known locally as Sumaum winds, these occur when hot, dry air from the interior desert sweeps toward the coast, carrying fine sand that turns the sky orange and sharply drops the humidity.
• Record Heat: While 40°C is standard, Jeddah has historically recorded extremes up to 52°C (125.6°F) during rare periods when the wind shifts to blow directly from the desert interior.

Microclimates and Coastal Influence

The climate varies significantly as you move inland. Within 15 kilometers of the shore, the Red Sea’s humidity dominates. However, if you travel just 30 to 45 minutes east toward the foothills, the humidity drops off sharply, and the heat becomes much drier. The "Old Jeddah" (Al-Balad) was architecturally designed for this climate; its tall, multi-story buildings and narrow alleys create shaded wind tunnels that naturally cool the city through the "stack effect."