Meridian (ID) Temperature by Month

Meridian, Idaho, United States of America has an average annual maximum temperature of 18°C (64°F), ranging from 3°C (37°F) in January to 34°C (93°F) in July. Below you'll find a full monthly breakdown and a comparison with cities worldwide.

The climate in Meridian is known for significant temperature differences throughout the year. At night, this contrast is just as clear, with lows ranging from 16°C (61°F) in July to -5°C (23°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Meridian 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 399 hours of sunshine.

The chart below shows the average temperature throughout the year:

Meridian's average annual maximum temperature is 18°C (64°F). To put that in context, here's how it compares to a few well-known destinations:

Rome, Italy averages 20°C (68°F) annually, with reliably warm summers and comfortable winters.

Interlaken, Switzerland averages 8°C (46°F) a year, with cold winters and cool summers thanks to its Alpine setting.

Seoul, South Korea averages 18°C (64°F) a year, with four clear seasons, cold winters, and hot humid 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 Meridian, January is the coolest month, with average highs of 3°C (37°F) and humidity around 75%, considered high. In July, the warmest month, temperatures average 34°C (93°F) with 36% humidity, conditions that feel low. 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 Meridian's weather, including monthly rainfall, sunshine hours, and humidity, visit our Meridian climate page.