Castel Gandolfo Temperature by Month
Castel Gandolfo in Lazio, Italy sees significant seasonal temperature differences, with daytime highs between 13°C (55°F) in January and 31°C (88°F) in August, averaging 21°C (70°F) annually. Explore the full monthly breakdown below.
Castel Gandolfo Monthly Temperatures
Visitors to Castel Gandolfo can expect significant temperature changes throughout the year. Nighttime temperatures also vary widely, ranging from 20°C (68°F) in August to 5°C (41°F) in January.
The chart below illustrates the average maximum day and minimum night temperatures in Castel Gandolfo by month:
The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM. August, the city's warmest month, gets 298 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Castel Gandolfo vs Italy
The map below shows the annual temperature across Italy. You can also select individual months if you want to compare a specific time of year.
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Castel Gandolfo vs World: Temperature Compared
Castel Gandolfo's average annual maximum temperature is 21°C (70°F). To put that in context, here's how it compares to a few well-known destinations:
Lisbon, Portugal averages 21°C (70°F) annually — warm summers, mild winters, and rain mainly in the cooler months.
Reykjavík, Iceland averages 9°C (48°F) a year — mild summers by Icelandic standards, but cold winters and frequent wind.
San Francisco, USA averages 19°C (66°F) annually, but with little seasonal variation — summers are often cool and foggy, winters mild.
Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.
What Does the Temperature Feel Like in Castel Gandolfo?
Temperature alone doesn't tell the whole story — humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.
In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.
In Castel Gandolfo, January is the coolest month, with average highs of 13°C (55°F) and humidity around 75% — considered high. In August, the warmest month, temperatures average 31°C (88°F) with 73% humidity — conditions that feel high. For a full picture, see our humidity page.
Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.
The readings come from a range of sources — land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.
For cities and regions with significant elevation, altitude is one of the biggest factors shaping local temperatures. As a rule of thumb, temperatures fall by around 6°C for every 1,000 metres gained — so a city at 2,000 metres will typically be around 12°C cooler than a city at sea level in the same region. Higher ground also tends to see more dramatic day-to-night temperature swings, since thinner air loses heat faster after sunset.
For more on Castel Gandolfo's weather — including monthly rainfall, sunshine hours, and humidity — visit our Castel Gandolfo climate page.
