Weather and climate in Pennside, PA
What the weather is like in Pennside
The warmest month in Pennside is July, with average highs of 85°F. The coolest is January, when nights average 20°F. About 48.5 in of rain and snow falls in a typical year, most in July and least in February.
Skies are clearest in September (52% average cloud cover) and cloudiest in December (68%). Combining cloud with the length of truly dark nights, November, October, September offer the most clear, dark hours for stargazing.
Clear, dark hours per night
Hours of full astronomical darkness in mid-month, multiplied by the average share of clear sky. A rough guide to how much good observing time a typical night offers.
Monthly averages
| Month | High | Low | Precipitation | Cloud cover | Humidity | Wind | Dark hours |
|---|---|---|---|---|---|---|---|
| January | 35°F | 20°F | 3.0 in | 66% | 87% | 2 mph | 11.2 h |
| February | 37°F | 21°F | 2.9 in | 64% | 86% | 2 mph | 10.2 h |
| March | 47°F | 28°F | 3.6 in | 63% | 82% | 2 mph | 9.0 h |
| April | 61°F | 38°F | 3.8 in | 62% | 78% | 1 mph | 7.4 h |
| May | 71°F | 50°F | 4.1 in | 64% | 79% | 1 mph | 5.8 h |
| June | 80°F | 59°F | 4.9 in | 59% | 77% | 1 mph | 4.8 h |
| July | 85°F | 65°F | 5.0 in | 54% | 72% | 1 mph | 5.3 h |
| August | 84°F | 63°F | 4.6 in | 54% | 72% | 1 mph | 6.8 h |
| September | 77°F | 56°F | 4.7 in | 52% | 73% | 1 mph | 8.5 h |
| October | 64°F | 44°F | 4.6 in | 58% | 79% | 1 mph | 9.8 h |
| November | 51°F | 33°F | 3.4 in | 60% | 82% | 1 mph | 10.9 h |
| December | 40°F | 25°F | 4.1 in | 68% | 87% | 1 mph | 11.4 h |
Climate averages: NASA POWER, 2001–2025, for the grid area around 40.50, -75.63 (about 50 km across). High and low temperatures are estimated from the monthly mean and the average daily range. Hills, coasts and cities can differ from the area average. Aurora outlook for Pennside · Sources and methods.