Sydney in December

In December, Sydney averages 25°C (77°F) during the day and 18°C (64°F) at night, with around 11 days of rain (78 mm total).

Peak season

Conditions are comfortable for sightseeing without being sweltering. Plan for unsettled weather and bring rain gear.

December offers comfortable temperatures in Sydney, with some rain to plan around.

25°C
Avg high
18°C
Avg low
11
Rain days
78 mm
Rainfall

How December compares to the rest of the year in Sydney

4th
warmest month of the 12
7th
wettest month of the 12
6%
of yearly rainfall falls in December
14 h 23 min
daylight on the 15th

December is in the middle of the year for warmth in Sydney (4th of 12) and moderately rainy compared to the rest of the year (7th of 12). Daytime temperature runs 3°C above the annual average (22°C). December runs 1°C warmer than November (24°C) and warms a further 1°C into January (26°C).

December sunrise & sunset in Sydney

🌅
Sunrise (15th)
5:38 AM
🌇
Sunset (15th)
8:01 PM
Day length
14 h 23 min

Times shown for Sydney local time (Australia/Sydney), calculated for the 15th of December. They shift by a few minutes day to day across the month.

Photography light in Sydney — December

Golden-hour and blue-hour windows for the 15th of December, in Sydney's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).

🌅 Blue hour (AM)
4:38 AM – 5:18 AM
🌄 Golden hour (AM)
5:18 AM – 6:18 AM
🌇 Golden hour (PM)
7:21 PM – 8:21 PM
🌆 Blue hour (PM)
8:21 PM – 9:01 PM

📅 When to book — Sydney in December

Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on December's tier (Peak season) and Sydney's popularity.

✈ Flights — lead time
4-6 months
Flight prices are near their annual peak. Watch fare-alert tools, book directly when you see a fare under the typical range for this city.
🏨 Lodging — lead time
5-7 months
Boutique hotels and tourist-zone properties fill 6 months out. If you're looking at a specific named hotel or rental, book it the moment you can.
⚠ Christmas / New Year travel is a global premium-pricing event — many destinations 30-50% above normal. Book 4+ months ahead if your dates are Dec 20 - Jan 2.

Crowds & pricing — December in Sydney

Peak season

Sydney is in peak season during this month — expect bigger crowds at famous sights, higher hotel and flight prices, and longer queues. Restaurant reservations a few days out are advisable, and any boutique hotels you have your eye on should be booked weeks ahead. The trade-off: most attractions, restaurants, and seasonal services are fully open, the weather is at its most reliable, and the city feels at its most alive.

Why this tier: excellent tourism weather

Sun & mosquito risk — December in Sydney

☀️ UV Index (noon, 15th)
12.7
Extreme
Stay indoors during midday hours; SPF 50+ even briefly outside, UPF clothing, wide-brim hat, sunglasses essential.
🦟 Mosquito risk
●●●●●
Severe
Severe mosquito season with active disease transmission risk. DEET 30%+, picaridin 20%, long sleeves day and night, treated nets, and check CDC/WHO travel advisories before going.

UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.

Sea temperature in Sydney — December

20.8°C (69°F)
pleasant
warm enough for most swimmers without a wetsuit

Across the year Sydney's sea swings from 17.7°C (July) to 23.4°C (February) — December sits at 20.8°C.

Sydney in other months

MonthAvg highAvg lowRainfallRain daysSnow days
January 26°C / 79°F 19°C / 66°F 102 mm 11
February 26°C / 79°F 19°C / 66°F 117 mm 11
March 25°C / 77°F 17°C / 63°F 130 mm 12
April 22°C / 72°F 14°C / 57°F 127 mm 11
May 19°C / 66°F 11°C / 52°F 121 mm 11
June 17°C / 63°F 9°C / 48°F 131 mm 11
July 17°C / 63°F 8°C / 46°F 98 mm 9
August 18°C / 64°F 9°C / 48°F 81 mm 9
September 20°C / 68°F 11°C / 52°F 69 mm 9
October 22°C / 72°F 13°C / 55°F 77 mm 10
November 24°C / 75°F 16°C / 61°F 84 mm 10
December 25°C / 77°F 18°C / 64°F 78 mm 11

Other cities with similar December weather

🌍 See the full ranked list of climate twins for Sydney in December →

Frequently asked questions

How hot is Sydney in December?

In December, Sydney averages a high of 25°C (77°F) and a low of 18°C (64°F) — generally warm.

Does it rain a lot in Sydney in December?

December can be fairly wet in Sydney, with about 11 rainy days on average.

Is December a good time to visit Sydney?

December is warm. It suits travelers who are comfortable with warm weather; check the month-by-month ranking to compare it against the rest of the year.

What should I pack for Sydney in December?

Pack light layers for warm days and cooler evenings, plus a compact umbrella or rain jacket. See the full December packing list for Sydney for a complete, climate-based checklist.

Open Sydney on the interactive map

Check the live 10-day forecast and sunrise/sunset.