Mercer County (Princeton)
October
Weather in Mercer County, New Jersey for October 2026
Your guide to Mercer County weather in October - trends and predictions
In general, the average temperature in Mercer County at the beginning of October is 21.7 °C. As the month progressed, temperatures tended to significantly cool down, reaching an average of 15.4 °C by the end of October.
Mercer County experiences moderate rainfall in October, with an average of 7 rainy days and a total precipitation of 135.4 mm.
New! Chat with our AI weatherman - it’s amazing and free.
Temperatures
Rain 🌧️
More
24
Dry days
7
Rainy days
0
Snow days
18°/8°
Temperatures
18 km/h
Avg max wind
68 %
Avg humidity
Mercer County Weather October
Move between months or click on a day
Temperatures trend during October in Mercer County
See the weather trend as well as the moving average line
October weather in Mercer County day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Oct. 1 |  Overcast | 19° /12° | 0 mm | 5 | |
| Oct. 2 | Overcast | 18° /12° | 0 mm | 5 | |
| Oct. 3 |  Cloudy | 20° /11° | 0 mm | 5 | |
| Oct. 4 |  Fog | 25° /14° | 0 mm | 6 | |
| Oct. 5 |  Partly cloudy | 25° /13° | 0 mm | 6 | |
| Oct. 6 | Partly cloudy | 23° /11° | 0 mm | 6 | |
| Oct. 7 |  Moderate or heavy rain with thunder | 22° /13° | 4.1 mm | 5 | |
| Oct. 8 | Cloudy | 19° /10° | 35.7 mm | 5 | |
| Oct. 9 |  Sunny | 17° /8° | 0 mm | 5 | |
| Oct. 10 | Sunny | 16° /4° | 0 mm | 5 | |
| Oct. 11 | Sunny | 18° /5° | 0 mm | 5 | |
| Oct. 12 | Overcast | 19° /11° | 22.2 mm | 5 | |
| Oct. 13 | Overcast | 19° /11° | 23.4 mm | 5 | |
| Oct. 14 | Partly cloudy | 18° /9° | 0.3 mm | 5 | |
| Oct. 15 | Cloudy | 15° /6° | 0 mm | 4 | |
| Oct. 16 | Sunny | 16° /4° | 0 mm | 5 | |
| Oct. 17 | Sunny | 14° /2° | 0 mm | 4 | |
| Oct. 18 | Sunny | 18° /5° | 0 mm | 5 | |
| Oct. 19 | Sunny | 22° /8° | 0 mm | 6 | |
| Oct. 20 | Mist | 20° /8° | 13.2 mm | 5 | |
| Oct. 21 | Sunny | 23° /7° | 0 mm | 7 | |
| Oct. 22 | Sunny | 24° /11° | 0 mm | 6 | |
| Oct. 23 | Mist | 20° /7° | 0 mm | 5 | |
| Oct. 24 | Overcast | 15° /5° | 0 mm | 4 | |
| Oct. 25 | Sunny | 15° /3° | 0 mm | 5 | |
| Oct. 26 |  Light rain shower | 16° /7° | 0.5 mm | 5 | |
| Oct. 27 | Overcast | 12° /5° | 0 mm | 3 | |
| Oct. 28 | Sunny | 13° /2° | 0 mm | 4 | |
| Oct. 29 | Overcast | 13° /5° | 5.2 mm | 3 | |
| Oct. 30 | Fog | 16° /8° | 30.8 mm | 4 | |
| Oct. 31 | Fog | 23° /10° | 0 mm | 5 | |
| Next | |||||
Important Notice
Our weather forecast for Mercer County in October 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.
Change Month
Mercer County in October - FAQ
What are the expected maximum and minimum temperatures in Mercer County during October?
Enjoy moderate daytime temperatures of up to 18° and cooler nights around 8°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Mercer County during October?
Significant rainfall exceeding 135.4 mm is expected in Mercer County during October, occurring over more than 7 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Mercer County during October?
The average wind speed in Mercer County during October is 18 km/h, suggesting breezy to windy conditions, depending on your activities.
October rainfall patterns in Mercer County
Explore the daily rainfall trends and prepare for Mercer Countys October weather 💧
Typically, Mercer County has 7 rainy days in October with a total of 135.4 mm of rainfall.
UV exposure in Mercer County during October
Stay informed about UV levels for safe outdoor activities throughout the month of October ☀️
Top locations in Mercer County
Select a location for an accurate weather forecast
More Locations Quick links
More Mercer County weather pages
You are here
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.
Found a mistake?
We appreciate your attention to details. Tell us here.