Skip to content
Sydney in December

Sydney Weather in December

🇦🇺 Australia

24°C
High
18°C
Low
9
Rain Days
11h
Sunshine
70%
Humidity

Oceania › 🇦🇺 Australia › Sydney

Updated: March 2026

Is December a Good Time to Visit Sydney?

7/10
Good

December is a good time to visit Sydney (7/10). With 11 daily sunshine hours and only 9 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 3rd sunniest of the year in Sydney. Culture-focused travellers and those who prefer lighter crowds will find December a practical choice, with prices running lower than peak January without sacrificing all the good weather. New Year's Eve Harbour Fireworks takes place this month, adding cultural value for those planning around it. The main practical note: Sydney's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: accommodation is generally available without long lead times, and flight prices are typically lower than peak season. Flexible travellers will find the best deals by booking 2-4 weeks ahead. Mid-week arrivals consistently unlock lower hotel rates than weekend check-ins.

vs November:23°C avg high

December sits at a particular moment in Sydney's seasonal arc. Temperatures average 24°C during the day, placing this month in a comfortable middle band, noticeably warmer than the depths of winter but without midsummer extremes. Against the seasonal backdrop, 9 rainy days and 11 sunshine hours per day help calibrate expectations for what actually awaits on the ground.

24°C

Avg High

18°C

Avg Low

9 days

Rain Days

11h

Sunshine

70%

Humidity

Temperature in Sydney in December

The 6°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 70%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 9 this month, classed as high to very high. SPF 30+ sunscreen, a brim hat, and sunglasses are not optional between 10am and 4pm. Wind averages 20 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 75°F average high, 64°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).

Temperature in December

Monthly Precipitation (mm)

What to Wear in Sydney in December

Morning18°CBefore the day warms up
Afternoon24°CPeak daytime temperature
Evening21°CAfter sunset cools down

Packing for Sydney in December means dressing for 24°C days and 18°C evenings. A light cotton tee with a casual overshirt works well at 24°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 18°C, a modest 6°C drop that a light cardigan or denim jacket covers. Comfortable walking trainers are the versatile choice for both outdoor sightseeing and indoor venues. A compact foldable umbrella weighs almost nothing and earns its keep across 9 potential rainy days.

💡

Local tip: Layers are more practical than a single heavy garment in Sydney. The day-to-evening temperature shift rewards packing a versatile mid-layer you can add or remove as conditions change.

Events in Sydney in December

New Year's Eve Harbour Fireworks

Festival

December 31

Sydney's Harbour Bridge hosts two fireworks displays: the 9pm family show and the midnight main event. Among the world's first major New Year's celebrations due to time zone. Harbour viewpoints fill 8 or more hours early.

Sydney

What to Pack for Sydney in December

Based on 24°C average highs and 9 rainy days

  • Light layers for morning and evening
  • Breathable T-shirts and comfortable trousers
  • UV-protective sunglasses
  • Compact folding umbrella
  • Waterproof outer layer or packable rain jacket
  • Quick-dry clothing that recovers fast after a shower
  • SPF 30+ sunscreen
  • Comfortable walking shoes (a second pair lets the first air out overnight)
  • Universal travel adapter
  • Small day pack for city exploration
  • Reusable water bottle

Best Activities in Sydney in December

  • Explore outdoor markets and street food stallsMid-morning (10am-12pm)At 24°C, the temperature is ideal for extended walking without overheating
  • Guided walking tour of the historic centreMorning or late afternoonComfortable temperatures allow several hours on foot without fatigue
  • Visit rooftop viewpoints and observation decksGolden hour (1 hour before sunset)Warm clear evenings provide exceptional visibility for panoramic photography
  • Day trip to the surrounding countryside or coastFull day (depart by 8am)December is reliably dry enough for rural day trips without weather risk
  • Afternoon in a world-class museum or galleryAfternoon (2-5pm)Pairs well with outdoor morning activities and provides a mid-day rest from sightseeing
  • Coffee-house or traditional cafe culture experienceMid-morning or post-lunchA cultural ritual in this region that rewards slow appreciation regardless of weather
  • Evening live music, theatre, or opera performanceEvening shows typically at 7-9pmConsistent evening temperatures make getting to and from evening venues comfortable
  • Attend New Year's Eve Harbour FireworksCheck specific event datesA once-yearly event that defines this city in this month and draws visitors from around the world
  • Try the seasonal farmer's market for local produce and street foodSaturday morning markets typically 8am-1pmDecember seasonal produce is at peak availability, offering dishes not found at other times of year

Why is Sydney mild in December?

December in Sydney reflects a mid-latitude climate pattern, with temperatures averaging 24°C by day and 18°C overnight. The city sits at 34 degrees south latitude, where the balance between solar radiation and heat loss drives conditions that are neither extreme nor static. Conditions occupy the comfortable middle band of the annual temperature range, where outdoor activity is feasible without the extremes of midsummer heat or midwinter cold. Day-to-night temperature variation of 6°C is moderate and manageable with a single mid-layer. Climate data: Open-Meteo ERA5 (1991–2020).

Sunshine Hours

The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.

UV Index

A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate -- wear sunscreen. UV 6-7: High -- hat and SPF 30+ essential. UV 8-10: Very High -- limit midday exposure. UV 11+: Extreme -- seek shade between 10am-4pm.

Rain Days

A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.

Humidity

Relative humidity as a percentage. Below 40%: Dry -- skin and throat may feel parched. 40-60%: Comfortable -- ideal for most people. 60-80%: Sticky -- light, breathable fabrics recommended. Above 80%: Muggy -- heat feels more intense; quick-dry clothing is essential.

Frequently Asked Questions: Sydney in December

In December, Sydney experiences average highs of 24°C (75°F) and lows of 18°C (64°F). Expect around 9 rainy days and 11 hours of sunshine per day, with humidity averaging 70%. The 6°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 9, so sun protection is advisable on clear days.
Sydney typically sees 9 rainy days in December, with total precipitation of around 55mm. Rain is moderate and manageable. Showers tend to pass quickly, and a light rain layer or foldable umbrella is sufficient protection for most days. For context, the driest month in Sydney typically sees 4-6 fewer rain days than December.
Pack light layers, a light jacket for evenings, comfortable walking shoes, and sunscreen for Sydney in December. Daytime temperatures of 24°C are pleasant, but the evening drop to 18°C means a jacket is essential if you plan to be out after dark. With 9 rainy days, bring a compact umbrella or waterproof jacket for unexpected showers. Comfortable walking shoes are a priority given the amount of ground most visitors cover.
Yes, December is an excellent time to visit Sydney. With 11 daily sunshine hours and only 9 rainy days, conditions are ideal for sightseeing and outdoor activities. Temperatures averaging 24°C during the day are comfortable for long walks and outdoor dining. This is peak travel season, so booking accommodation in advance and arriving at popular attractions early in the morning helps avoid the busiest periods.
The average high temperature in Sydney in December is 24°C (75°F), and the average low is 18°C (64°F). The mean daily temperature is approximately 21°C (70°F). The day-to-night range of 6°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Sydney is generally January. January offers the most sunshine at 11 hours per day and only 9 rainy days. Average temperatures reach 26°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around January gives you the best chance of dry, bright weather.
December is shoulder or low season in Sydney, meaning fewer tourists and generally lower prices than peak months. With 11 sunshine hours and 9 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In December, Sydney suits a range of activities thanks to mild temperatures around 24°C. Mix of indoor and outdoor activities works well given the moderate chance of rain. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 11 hours of sunshine, parks and waterfront walks are particularly enjoyable.

December ranks 3rd sunniest of the year in Sydney, with an average 11 daily sunshine hours. The driest months are August, July, and September. January is the hottest month (26°C avg high); June is the coolest (16°C). From here, temperatures rise 2°C into January. Compared to last month (November: 23°C high, 9 rain days), December is warmer and equally dry. December is among the top three sunniest months to visit Sydney.

Year-Round Climate

MonthHighLowRain DaysSunDetails
January26°C19°C911hView
February25°C19°C1010hView
March24°C18°C1010hView
April21°C15°C89hView
May19°C12°C78hView
June16°C10°C88hView
July16°C9°C68hView
August17°C9°C59hView
September19°C11°C610hView
October21°C14°C810hView
November23°C16°C911hView
December24°C18°C911hView

Other Months in Sydney

JanFebMarAprMayJunJulAugSepOctNovDec

Plan Your Trip to Sydney

Best Time to Visit Sydney

Data Sources for Sydney

Sydney on WikipediaOpen-Meteo Climate APINOAA National CentersUK Met OfficeWMOGeoNames

Climate normals represent 30-year averages (1991-2020). Individual years may vary.