July weather forecast
Philadelphia, PA

The heat of the mid-summer month of July is in full effect in Philadelphia, Pennsylvania, with temperatures reaching their highest for the year, soaring to an average of 86.4°F (30.2°C). Compared to June, July also sees a small increase in rainfall, measuring at 1.54" (39mm). The splendid, sunny weather makes for ideal conditions for outdoor picnics and jaunts to the beach. Though temperatures remain high throughout the day and night, a mild wind blows consistently, providing some relief. As summer progresses, the city continues to bask in warm, sunny days.

Temperature

July brings the highest temperatures, with an average high of 86.4°F (30.2°C) and an average low of 69.3°F (20.7°C).

Heat index

The heat index value for July is evaluated at a very hot 96.8°F (36°C). Exercise special caution, heat exhaustion and heat cramps are probable. Prolonged activity may induce heatstroke.
Data suggests that the heat index is set for environments in shade and with a light wind. A rise in the heat index by 15 Fahrenheit (8 Celsius) degrees may result from direct sunlight exposure.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', gauges the sensation of temperature factoring in the air's moisture content. A person's impression of weather can be swayed by numerous aspects, among them metabolic variations, pregnancy, and activity levels. Direct sun exposure is noteworthy in its ability to escalate the felt temperature, potentially adding 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values are especially vital to children. Young ones regularly neglect the requirement for rest and fluid replenishment. Thirst is a late stage of dehydration - so, it is necessary to keep hydrated, particularly during extended periods of physical exertion.
When temperatures rise, the human body turns to perspiration, using the cooling power of evaporating sweat. An upsurge in relative humidity affects normal body cooling mechanisms by slowing evaporation, hence reducing the rate at which the body cools and intensifying the perception of heat. Exceeding the body's heat disposal threshold results in a rise in body temperature and potential thermal disorders.

Humidity

In Philadelphia, the average relative humidity in July is 72%.

Rainfall

In July, the rain falls for 14.8 days. Throughout July, 1.54" (39mm) of precipitation is accumulated. In Philadelphia, during the entire year, the rain falls for 127.8 days and collects up to 13.82" (351mm) of precipitation.

Snowfall

In Philadelphia, snow does not fall in June through October.

Ocean temperature

In Philadelphia, the average seawater temperature in July is 73.9°F (23.3°C).
Note: Individual cold sensitivities, influenced by sunshine, wind, and the ambient temperature, play a role in finding a swim in 73.9°F (23.3°C) water pleasant. (Olympic swimming events mandate water temperatures from 77°F (25°C) to 82.4°F (28°C).)

Daylight

The average length of the day in July is 14h and 41min.
On the first day of July, sunrise is at 5:36 am and sunset at 8:33 pm. On the last day of the month, sunrise is at 5:58 am and sunset at 8:15 pm EDT.

Sunshine

The month with the most sunshine is July, with an average of 10.6h of sunshine.

UV index

May through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV rays for the ordinary person.
Note: A daily maximum UV index of 6 in July translates into the following instructions:
Avoid overexposure. Fair-skinned individuals can burn in under 20 minutes. Stay in the shade and limit direct sun exposure between 10 a.m. and 4 p.m., when UV radiation is at its strongest. Remember, however, that not all shade structures provide full sun protection. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Warning! Reflective surfaces like sand and water amplify the Sun's UV radiation.