Henlopen Keys Temperature by Month

Henlopen Keys in United States of America sees significant seasonal temperature differences, with daytime highs between 7°C (45°F) in January and 31°C (88°F) in July, averaging 19°C (66°F) annually. Explore the full monthly breakdown below.

Visitors to Henlopen Keys can expect significant temperature changes throughout the year. Nighttime temperatures also vary widely, ranging from 22°C (72°F) in July to -2°C (28°F) in January.

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

From around 4 AM to 6 AM temperatures are at their lowest; by 3 PM they've climbed to their daily peak.

The chart below shows the average temperature throughout the year:

Henlopen Keys's average annual maximum temperature is 19°C (66°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.

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

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.

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