Boulder City (NV) Temperature by Month

The average annual maximum temperature in Boulder City, Nevada, United States of America is 27°C (81°F), with daytime highs ranging from 13°C (55°F) in December to 40°C (104°F) in July. This page covers monthly averages, day-night differences, and how Boulder City compares to cities worldwide.

Visitors to Boulder City will encounter a climate influenced by big temperature differences across the year. Nighttime temperatures range from 27°C (81°F) in July to 4°C (39°F) in December.

The chart below illustrates the average maximum day and minimum night temperatures in Boulder City 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 383 hours of sunshine.

The chart below shows the average temperature throughout the year:

Boulder City's average annual maximum temperature is 27°C (81°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.

Boston, USA averages 16°C (61°F) annually, with four distinct seasons and cold winters that rival northern Europe.

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 Boulder City, December is the coolest month, with average highs of 13°C (55°F) and humidity around 45%, considered moderate. In July, the warmest month, temperatures average 40°C (104°F) with 21% 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.

Global average temperatures have risen by around 1.2°C since the pre-industrial era, and the effects are visible across many regions. Winters are milder on average, with fewer frost days and less snow in many parts of the world. Heatwaves are more frequent and more intense, and Europe's summers of 2018, 2019, and 2020 all set records.

Summers are also getting drier in some areas, while winter rainfall has increased in others. This contributies to higher river levels and more flooding. In many countries, spring arrives earlier and autumn lasts longer. It has knock-on effects for wildlife, agriculture, and local ecosystems.

For more on Boulder City's weather, including monthly rainfall, sunshine hours, and humidity, visit our Boulder City climate page.