July weather forecast
Ashburn, VA

July in Ashburn is the zenith of summer heat, with temperatures reaching their peak, higher than June and August. The relative humidity remains balanced, providing a comforting counterpoint to the increasing heat. The highest temperature recorded in July is a blistering 87.8°F (31°C), signifying the intensity of summer. However, the frequency of rain offers short relief, matching the frequency experienced in June.

Temperature

With average high and low temperatures of 87.8°F (31°C) and 67.3°F (19.6°C) respectively, July is Ashburn's warmest month.

Heat index

For most parts of July, the heat index is computed to be a very hot 100.4°F (38°C). Ensure extra safety measures, heat exhaustion and heat cramps are likely. Continuous activity might result in heatstroke.
One should consider that heat index numbers are for shaded settings and light wind. The heat index could experience an increase of 15 Fahrenheit (8 Celsius) degrees due to direct sunlight.
Note: The heat index, also known as 'real feel' or 'felt air temperature', binds temperature metrics with humidity values to give a sense of the actual warmth. The experience of temperature can be subjective, varying based on the individual's activity and heat perception, influenced by factors like wind, attire, and metabolic variations. Awareness is key; direct sunlight can enhance the weather's impact, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values hold great significance to children. Children often lack awareness of the importance of taking breaks and rehydrating. The feeling of thirst is a late indication of dehydration, so maintaining hydration, especially during long periods of physical activity, is critical.
The body's innate mechanism to counteract overheating is through perspiration, as it leverages the cooling effects of sweat evaporation. When the air contains significant moisture, the efficiency of the evaporation process decreases, preventing the body from cooling down effectively and creating a feeling of overheating. Increasing body temperatures can be a precursor to dehydration if the body can't shed the extra heat.

Humidity

The least humid month is July, with an average relative humidity of 70%.

Rainfall

In Ashburn, during July, the rain falls for 16.3 days and regularly aggregates up to 3.03" (77mm) of precipitation. Throughout the year, there are 158.1 rainfall days, and 31.46" (799mm) of precipitation is accumulated.

Snowfall

In Ashburn, snow does not fall in May through October.

Daylight

In July, the average length of the day is 14h and 35min.
On the first day of July in Ashburn, sunrise is at 5:48 am and sunset at 8:39 pm. On the last day of the month, sunrise is at 6:10 am and sunset at 8:22 pm EDT.

Sunshine

The month with the most sunshine is July, with an average of 10.7h of sunshine.

UV index

The months with the highest UV index are May through August, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for ordinary individuals.
Note: The UV index of 6 during July leads to these advisories:
Take precautions against overexposure. Protection against sun damage is needed. Seek shade and limit direct Sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its peak, but be aware that not all shade structures provide complete sun protection. Enhance your sun protection with tightly woven, yet airy clothing.