Mercer County (Princeton)
July
Weather in Mercer County, New Jersey for July 2026
Your guide to Mercer County weather in July - trends and predictions
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So far, July 2026 in Mercer County is slightly warmer than the historical average by 0.7 °C.
The forecast for the upcoming days in Mercer County predicts a temperature of 29.1 °C, which is slightly above the historical average.
In general, the average temperature in Mercer County at the beginning of July is 31 °C. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 28.1 °C by the end of July.
Mercer County experiences heavy rainfall in July, with over 20 rainy days and an average total precipitation 194.3 mm.
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Temperatures
Rain 🌧️
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5
Dry days
26
Rainy days
0
Snow days
30°/20°
Temperatures
15 km/h
Avg max wind
72 %
Avg humidity
Mercer County Weather July
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Temperatures trend during July in Mercer County
See the weather trend as well as the moving average line
July weather in Mercer County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Jul. 1 |  Partly cloudy | 33° /19° | 14.6 mm | 9 | |
| Jul. 2 |  Sunny | 33° /20° | 5.7 mm | 8 | |
| Jul. 3 | Sunny | 33° /20° | 1 mm | 9 | |
| Jul. 4 |  Patchy light drizzle | 31° /18° | 1.9 mm | 8 | |
| Jul. 5 |  Light rain shower | 30° /20° | 10.8 mm | 8 | |
| Jul. 6 | Light rain shower | 29° /20° | 15.3 mm | 6 | |
| Jul. 7 | Partly cloudy | 28° /21° | 9.5 mm | 5 | |
| Jul. 8 | Patchy rain possible | 31° /20° | 1.4 mm | 9 | |
| Jul. 9 | Patchy light drizzle | 30° /22° | 7.1 mm | 8 | |
| Jul. 10 | Patchy rain possible | 31° /22° | 4.1 mm | 8 | |
| Jul. 11 |  Fog | 29° /21° | 2.8 mm | 8 | |
| Jul. 12 | Light rain shower | 30° /20° | 2.4 mm | 8 | |
| Jul. 13 | Light rain shower | 30° /20° | 1.6 mm | 8 | |
| Jul. 14 | Partly cloudy | 32° /20° | 0 mm | 9 | |
| Jul. 15 |  Patchy light rain with thunder | 34° /22° | 9.6 mm | 9 | |
| Jul. 16 | Patchy rain possible | 34° /21° | 5.9 mm | 9 | |
| Jul. 17 | Patchy rain possible | 33° /22° | 1.2 mm | 9 | |
| Jul. 18 | Light rain shower | 29° /21° | 14.4 mm | 8 | |
| Jul. 19 | Sunny | 27° /18° | 2.4 mm | 8 | |
| Jul. 20 |  Cloudy | 30° /18° | 4.3 mm | 8 | |
| Jul. 21 | Sunny | 31° /19° | 8.6 mm | 8 | |
| Jul. 22 | Patchy rain possible | 29° /20° | 1 mm | 8 | |
| Jul. 23 | Sunny | 27° /16° | 0 mm | 8.5 | |
| Jul. 24 | Sunny | 29° /15° | 0 mm | 8.8 | |
| Jul. 25 | Sunny | 28° /16° | 0 mm | 7 | |
| Jul. 26 | Sunny | 30° /15° | 0 mm | 7 | |
| Jul. 27 | Patchy rain possible | 28° /19° | 7.4 mm | 7 | |
| Jul. 28 | Partly cloudy | 30° /20° | 4.5 mm | 7 | |
| Jul. 29 | Sunny | 29° /19° | 1.8 mm | 7 | |
| Jul. 30 | Light rain shower | 23° /18° | 25.2 mm | 5 | |
| Jul. 31 | Sunny | 29° /17° | 0 mm | 7 | |
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Important Notice
Our weather forecast for Mercer County in July is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Mercer County forecast closer to your planned date for the most up-to-date weather information.
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Mercer County in July - FAQ
What are the expected maximum and minimum temperatures in Mercer County during July?
Expect warm days with temperatures around 30°, cooling to mild conditions of 20° after sunset. Perfect for those who enjoy warm weather.
How much rainfall should be expected in Mercer County during July?
Significant rainfall exceeding 194.3 mm is expected in Mercer County during July, occurring over more than 26 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Mercer County during July?
The average wind speed in Mercer County during July is 15 km/h, suggesting breezy to windy conditions, depending on your activities.
July rainfall patterns in Mercer County
Explore the daily rainfall trends and prepare for Mercer Countys July weather 💧
Typically, Mercer County has 26 rainy days in July with a total of 194.3 mm of rainfall.
UV exposure in Mercer County during July
Stay informed about UV levels for safe outdoor activities throughout the month of July ☀️
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Where is Mercer County?Get accurate weather forecasts for Mercer County, located at latitude 40.349 and longitude -74.659. Stay updated with localized weather information tailored for Mercer County.
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