Mercer (PA) Temperature by Month

Mercer in Pennsylvania, United States of America sees significant seasonal temperature differences, with daytime highs between 1°C (34°F) in January and 28°C (82°F) in July, averaging 15°C (59°F) annually. Explore the full monthly breakdown below.

Depending on the time of the year, temperatures range from warm to very cold in Mercer. Nighttime lows follow the same pattern, ranging from 15°C (59°F) to -9°C (16°F).

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

Temperatures tend to bottom out between 4 AM and 6 AM, then climb to their daily peak around 3 PM.

The chart below shows the average temperature throughout the year:

Mercer's average annual maximum temperature is 15°C (59°F). To put that in context, here's how it compares to a few well-known destinations:

Seville, Spain averages 23°C (73°F) a year, one of the warmer cities in Western Europe, with long hot summers.

Queenstown, New Zealand averages 10°C (50°F) annually, remember seasons are flipped, so its coldest months fall in June and July.

Chicago, USA averages 15°C (59°F) annually, known for extreme seasonal swings, from bitterly cold winters to warm summers.

Brisbane, Australia averages 26°C (79°F) a year, with warm winters and hot, humid summers.

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.

Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round, large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.

For more on Mercer's weather, including monthly rainfall, sunshine hours, and humidity, visit our Mercer climate page.