Delta Temperature by Month

The average annual maximum temperature in Delta, Rideau Lakes, Canada is 13°C (55°F), with daytime highs ranging from -2°C (28°F) in January to 27°C (81°F) in July. This page covers monthly averages, day-night differences, and how Delta compares to cities worldwide.

Depending on the time of the year, temperatures range from warm to very cold in Delta. Nighttime lows follow the same pattern, ranging from 17°C (63°F) to -12°C (10°F).

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

The coolest part of the day is typically between 4 AM and 6 AM, while 3 PM is usually the warmest, when solar heating is at its peak. July, the city's warmest month, averages 280 hours of sunshine.

The chart below shows the average temperature throughout the year:

Delta's average annual maximum temperature is 13°C (55°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.

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.

Tokyo, Japan averages 21°C (70°F) a year, with hot summers, cool winters, and a well-defined cherry blossom spring.

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 Delta's weather, including monthly rainfall, sunshine hours, and humidity, visit our Delta climate page.