New Jersey · county areal climate 1951–2025

Mercer County, NJ

A 54.5°F / 47.5" normal · 2025 ran -0.5°F vs normal.
2026 so far · through Jul 9: This area is running -0.3°F (50.2°F) vs the 1996–2025 to-date normal — the 55th coldest start of 76 years. Precipitation 74% of normal. U.S. year-to-date →

Normal (1996–2025)

54.5°F
annual mean · 47.5" precipitation

2025 vs Normal

-0.5°F
54.0°F · 37.8" (80% of normal)

Warmest Year

56.2°F
2012 · coldest 50.6°F (1958)

Wettest Year

64.5in
2018 · driest 29.9" (1965)

Hottest Day

103.5°F
Jul 7 · 2010

Coldest Day

-10.1°F
Jan 22 · 1961

Biggest Rain Day

7.77in
Aug 28 · 2011

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

32°
J
35°
F
42°
M
52°
A
62°
M
71°
J
76°
J
74°
A
68°
S
56°
O
46°
N
37°
D
—— normal temperature (°F) · ▮ normal precipitation (in) · 1996–2025
Areal nClimGrid averages (NOAA/NCEI) over the whole area — an average across the region, not a single station. Separate from the station records.

Nearby

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part of Weather Trader · supported by Substack Subscribers · data: NWS NDFD forecast + NOAA/ACIS ThreadEx records · updated 2026-07-12 17:59Z
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