Mercer County (Princeton)
May
Weather in Mercer County, New Jersey for May 2026
Your guide to Mercer County weather in May - trends and predictions
The forecast for the next days in Mercer County predicts temperatures to be around 20 °F, close to the historical average.
In general, the average temperature in Mercer County at the beginning of May is 20.6 °F. As the month progressed, temperatures tended to moderately rise, reaching an average of 22.1 °F by the end of May.
Mercer County experiences heavy rainfall in May, with over 20 rainy days and an average total precipitation 340.7 mm.
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Temperatures
Rain 🌧️
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8
Dry days
23
Rainy days
0
Snow days
20°/12°
Temperatures
17 km/h
Avg max wind
78 %
Avg humidity
Mercer County Weather May
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Temperatures trend during May in Mercer County
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May weather in Mercer County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| May 1 |  Cloudy | 18° /8° | 0.2 mm | 6 | |
| May 2 | Cloudy | 22° /10° | 0.2 mm | 6 | |
| May 3 |  Partly cloudy | 21° /11° | 1.1 mm | 7 | |
| May 4 |  Light drizzle | 19° /11° | 4.1 mm | 6 | |
| May 5 | Light rain | 19° /12° | 17 mm | 5 | |
| May 6 |  Patchy rain possible | 27° /17° | 2.3 mm | 0.9 | |
| May 7 | Patchy rain possible | 18° /10° | 0.2 mm | 1.5 | |
| May 8 | Partly cloudy | 16° /6° | 0.1 mm | 0.9 | |
| May 9 |  Moderate rain | 17° /9° | 5 mm | 3 | |
| May 10 | Patchy rain possible | 23° /8° | 0.2 mm | 4 | |
| May 11 | Patchy rain possible | 17° /9° | 0.8 mm | 3 | |
| May 12 |  Sunny | 15° /7° | 0 mm | 4 | |
| May 13 | Patchy rain possible | 19° /7° | 0.3 mm | 3 | |
| May 14 | Partly cloudy | 25° /13° | 0 mm | 5 | |
| May 15 | Patchy rain possible | 20° /11° | 0.1 mm | 4 | |
| May 16 | Patchy rain possible | 19° /9° | 0.2 mm | 3 | |
| May 17 | Sunny | 21° /8° | 0 mm | 4 | |
| May 18 | Patchy rain possible | 16° /11° | 1.9 mm | 3 | |
| May 19 | Partly cloudy | 26° /14° | 0 mm | 5 | |
| May 20 |  Mist | 20° /9° | 0 mm | 5 | |
| May 21 | Sunny | 20° /11° | 23.8 mm | 5 | |
| May 22 | Patchy rain possible | 20° /12° | 14.3 mm | 5 | |
| May 23 | Patchy light rain | 20° /12° | 1.4 mm | 5 | |
| May 24 | Sunny | 22° /11° | 0 mm | 6 | |
| May 25 | Patchy rain possible | 23° /11° | 0 mm | 5 | |
| May 26 | Patchy light rain | 24° /14° | 4.3 mm | 5 | |
| May 27 | Light rain shower | 21° /14° | 13.8 mm | 5 | |
| May 28 | Partly cloudy | 20° /13° | 20.2 mm | 5 | |
| May 29 | Light rain shower | 23° /12° | 5.4 mm | 5 | |
| May 30 | Light rain shower | 22° /14° | 42.3 mm | 5 | |
| May 31 | Cloudy | 22° /11° | 30.1 mm | 5 | |
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Important Notice
Our weather forecast for Mercer County in May 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 May - FAQ
What are the expected maximum and minimum temperatures in Mercer County during May?
Enjoy moderate daytime temperatures of up to 20° and cooler nights around 12°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Mercer County during May?
Significant rainfall exceeding 340.7 mm is expected in Mercer County during May, occurring over more than 23 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Mercer County during May?
The average wind speed in Mercer County during May is 17 km/h, suggesting breezy to windy conditions, depending on your activities.
May rainfall patterns in Mercer County
Explore the daily rainfall trends and prepare for Mercer Countys May weather 💧
Typically, Mercer County has 23 rainy days in May with a total of 340.7 mm of rainfall.
UV exposure in Mercer County during May
Stay informed about UV levels for safe outdoor activities throughout the month of May ☀️
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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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