July weather forecastDerry, PA
July
Weather in July
July, like June, in Derry, Pennsylvania, is another warm summer month, with an average temperature ranging between max 81.1°F (27.3°C) and min 59.5°F (15.3°C).Temperature
July registers as the month with the highest average temperatures, reaching 81.1°F (27.3°C) at its peak and 59.5°F (15.3°C) at the lowest.Heat index
The average heat index in July is computed to be a tropical 86°F (30°C). Exhaustion is likely with prolonged exposure and activity. Sustaining activity may result in heat cramps.Records show heat index calculations are tailored for shaded regions and mild winds. An exposure to direct sunlight may lift the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', gauges the sensation of temperature factoring in the air's moisture content. A person's impression of weather can be affected by numerous aspects, among them metabolic variations, pregnancy, and activity levels. Taking into account that direct sunlight can boost the heat effect, the heat index may rise by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Children frequently underestimate the importance of resting and drinking fluids. Thirst is a symptom of advanced dehydration - hence the need to hydrate regularly, especially during protracted physical exercises.
Humidity
The months with the lowest humidity are April, July and August, with an average relative humidity of 78%.Rainfall
In July, the rain falls for 16.6 days. Throughout July, 1.89" (48mm) of precipitation is accumulated. In Derry, during the entire year, the rain falls for 156.2 days and collects up to 19.45" (494mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
The average length of the day in July is 14h and 43min.On the first day of July, sunrise is at 5:51 am and sunset at 8:51 pm. On the last day of the month, sunrise is at 6:14 am and sunset at 8:32 pm EDT.
Sunshine
The months with the most sunshine are July and August, with an average of 10h of sunshine.UV index
June and July, with an average maximum UV index of 6, are months with the highest UV index. A UV Index value of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV radiation for the average person.Note: A typical high UV index of 6 in July suggests the following recommendations:
Take precautions against overexposure. Protection against sun damage is needed. Avoid direct exposure to the Sun between 10 a.m. and 4 p.m., the peak period for UV radiation, noting that objects like parasols or canopies might not offer complete sun protection. To cut down UV radiation exposure by about half, sport a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in July
Derry, PA
- Average high temperature in July: 81.1°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (32.2°F).
- Average low temperature in July: 59.5°F
The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).
Average pressure in July
Derry, PA
- Average pressure in July: 29.98"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in July
Derry, PA
- Average wind speed in July: 5.2mph
The windiest month (with the highest average wind speed) is January (9.2mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity in July
Derry, PA
- Average humidity in July: 78%
The months with the highest relative humidity are January and February (86%).
The months with the lowest relative humidity are April, July and August (78%).
Average rainfall in July
Derry, PA
- Average rainfall in July: 1.89"
The wettest month (with the highest rainfall) is May (2.32").
The driest month (with the least rainfall) is November (1.02").
Average rainfall days in July
Derry, PA
- Average rainfall days in July: 16.6 days
The month with the highest number of rainy days is May (19.8 days).
The month with the least rainy days is January (7.6 days).
Average snowfall in July
Derry, PA
- Average snowfall in July: 0"
The month with the highest snowfall is January (3.94").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in July
Derry, PA
- Average snowfall days in July: 0 days
The month with the highest number of snowfall days is January (13.1 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in July /
Average sunshine in July
Derry, PA
- Average daylight in July: 14h and 42min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in July: 10h
The months with the most sunshine are July and August (Average sunshine: 10h).
The month with the least sunshine is January (Average sunshine: 3h).
Average sunshine days in July
Derry, PA
- Average sunshine days in July: 12 days
The month with the most sunshine days is November (18 days).
The month with the least sunshine days is May (8.9 days).
Average UV index in July
Derry, PA
- Average UV index in July: 6
The months with the highest UV index are June and July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in July
Derry, PA
- Average cloud cover in July: 37
The month with the most cloud cover is January (Cloud cover 70).
The month with the least cloud cover is August (Cloud cover 36).
Average visibility in July
Derry, PA
- Average visibility in July: 5mi
The months with the highest visibility are April and November (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October and December (5mi).





