Preston (CT) Temperature by Month

Preston in Connecticut, United States of America sees significant seasonal temperature differences, with daytime highs between 3°C (37°F) in January and 29°C (84°F) in July, averaging 16°C (61°F) annually. Explore the full monthly breakdown below.

In Preston, temperatures can shift dramatically between warm in summer and cold in winter. Nights follow the same pattern, with lows ranging from 18°C (64°F) in July to -7°C (19°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Preston by month:

Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating. July, the warmest month of the year, receives 290 hours of sunshine.

The chart below shows the average temperature throughout the year:

Preston's average annual maximum temperature is 16°C (61°F). To put that in context, here's how it compares to a few well-known destinations:

Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.

On the cooler end, Oslo, Norway averages just 10°C (50°F) annually, with pleasant summers but long, cold winters.

Chicago, USA averages 15°C (59°F) annually, known for extreme seasonal swings, from bitterly cold winters to warm summers.

Melbourne, Australia averages 20°C (68°F) annually, known for unpredictable weather, with four seasons sometimes happening in one day.

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 Preston, January is the coolest month, with average highs of 3°C (37°F) and humidity around 64%, considered high. In July, the warmest month, temperatures average 29°C (84°F) with 71% 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 Preston's weather, including monthly rainfall, sunshine hours, and humidity, visit our Preston climate page.