Walnut (IA) Temperature by Month
Walnut, Iowa, United States of America has an average annual maximum temperature of 15°C (59°F), ranging from -1°C (30°F) in January to 29°C (84°F) in July. Below you'll find a full monthly breakdown and a comparison with cities worldwide.
Walnut Monthly Temperatures
Depending on the time of the year, temperatures range from comfortable to very cold in Walnut. At night, minimum temperatures range from 17°C (63°F) in July to -12°C (10°F) in January.
The chart below illustrates the average maximum day and minimum night temperatures in Walnut by month:
Temperatures tend to bottom out between 4 AM and 6 AM, then climb to their daily peak around 3 PM. July, the warmest month, sees 335 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Walnut vs the United States of America
The map below shows the annual temperature across the United States of America. You can also select individual months if you want to compare a specific time of year.
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Walnut vs World: Temperature Compared
Walnut's average annual maximum temperature is 15°C (59°F). To put that in context, here's how it compares to a few well-known destinations:
Seville, Spain averages 23°C (73°F) a year — one of the warmer cities in Western Europe, with long hot summers.
Interlaken, Switzerland averages 8°C (46°F) a year, with cold winters and cool summers thanks to its Alpine setting.
Shanghai, China averages 21°C (70°F) a year, with warm summers, mild winters, and a noticeable spring and autumn.
Perth, Australia averages 25°C (77°F) annually, with a classic Mediterranean climate — hot dry summers and mild wet winters.
What Does the Temperature Feel Like in Walnut?
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 Walnut, January is the coolest month, with average highs of -1°C (30°F) and humidity around 71% — considered high. In July, the warmest month, temperatures average 29°C (84°F) with 67% 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.
Seasonal temperature shifts influence more than just how warm it feels — they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.
Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in Walnut this rarely lasts long on the ground.
For more on Walnut's weather — including monthly rainfall, sunshine hours, and humidity — visit our Walnut climate page.
