National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

Trenton-Mercer Airport (KTTN)

Lat: 40.28°NLon: 74.82°WElev: 210ft.

Fair

92°F

33°C

Humidity 38%
Wind Speed SW 10 G 18 mph
Barometer 30.12 in (1019.0 mb)
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Heat Index93°F (34°C)
Last update 18 May 1:53 pm EDT
Extended Forecast for

Princeton NJ

Heat Advisory May 18, 02:44pm until May 20, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory May 18, 02:44pm until May 20, 08:00pm

    NOW until 8:00pm Wed

    Heat Advisory

  • This Afternoon

    High: 92 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 69. Southwest wind 5 to 10 mph.

    Low: 69 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 95. West wind 5 to 10 mph.

    High: 95 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 73. Southwest wind 5 to 10 mph.

    Low: 73 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Showers and possibly a thunderstorm after 2pm. High near 92. West wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 92 °F

    Sunny then
    Showers

  • Wednesday Night

    Wednesday Night: Showers, mainly before 8pm. Low around 55. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 55 °F

    Showers then
    Chance
    Showers

  • Thursday

    Thursday: Partly sunny, with a high near 71.

    High: 71 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 50.

    Low: 50 °F

    Mostly Cloudy

Detailed Forecast

This Afternoon
Sunny, with a high near 92. South wind 5 to 10 mph.
Tonight
Mostly clear, with a low around 69. Southwest wind 5 to 10 mph.
Tuesday
Mostly sunny, with a high near 95. West wind 5 to 10 mph.
Tuesday Night
Partly cloudy, with a low around 73. Southwest wind 5 to 10 mph.
Wednesday
Showers and possibly a thunderstorm after 2pm. High near 92. West wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
Showers, mainly before 8pm. Low around 55. Chance of precipitation is 80%. New precipitation amounts of less than a tenth of an inch possible.
Thursday
Partly sunny, with a high near 71.
Thursday Night
Mostly cloudy, with a low around 50.
Friday
A chance of showers after 8am. Partly sunny, with a high near 66. Chance of precipitation is 40%.
Friday Night
Showers likely, mainly after 2am. Mostly cloudy, with a low around 50. Chance of precipitation is 70%.
Saturday
Showers likely. Mostly cloudy, with a high near 68. Chance of precipitation is 70%.
Saturday Night
Showers likely. Mostly cloudy, with a low around 55. Chance of precipitation is 60%.
Sunday
A chance of showers. Mostly cloudy, with a high near 72. Chance of precipitation is 50%.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Princeton NJ
 40.37°N 74.67°W (Elev. 256 ft)
Last Update:
4:09 am EDT May 18, 2026
Forecast Valid:
2pm EDT May 18, 2026-6pm EDT May 24, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation