TRENTON, NEW JERSEY
OFFICIAL NARRATIVE CLIMATOLOGICAL SUMMARY

The following was transcribed from the National Climatic Data Center's Annual Local Climatological Summary:

Trenton, on the east bank of the Delaware River, is situated at the western end of the "waistline" of New Jersey.  
The terrain is comparatively flat, sloping gently upward from near sea level in the city to about 500 feet 10 miles
to the north and northwest.  Although only approximately 40 miles from the Atlantic Ocean, its climate is largely 
continental, chiefly as a result of the predominance of winds from the interior of North America.

The Appalachian Mountains to the west exert a moderating influence on the climate, particularly in winter, 
protecting this area from the many outbreaks of arctic air that sweep southeastwards across the central United 
States and Canada.  The coldest weather is experienced when the cold "highs" of winter move or develop over eastern
Canada, allowing a more north-south flow of air into this area unmitigated by the Appalachian Mountains and/or the
Great Lakes.  The hottest summer weather occurs with a west to southwest flow of air, reflecting the effects of its 
long trajectory over land.  These heat waves of summer, however, are not normally as severe or extended as those 
experienced in the interior of the United States, although intervals of high temperature and humidity do often 
occur and cause considerable discomfort for short periods.  Thus the moderating influences of the Appalachian 
Mountains, the Atlantic Ocean, and, to a lesser extent, the Great Lakes are clearly exhibited and are further 
emphasized by the relatively mild extremes of temperature that have been recorded at Trenton.  For example:  0F or
below has been recorded on the average only one winter in eight, and similarly, 100F or above has been recorded on
the average only one summer in five.

Precipitation is moderate and well distributed throughout the year, summer totals being only slightly higher than
those of winter.  During the warm months most of the precipitation is produced by showers and thunderstorms, 
whereas in the cool season it is associated with more widespread storms.  A considerable amount of precipitation 
results from coastal storms which are most common during the cool season.  These "northeasters" often last for 1 to
2 days and account for most of the snowfall of this area.  Occasiionally during autumn or late summer they are of 
tropical origin and result in the heaviest and most extended rain experienced in this region.

Winds normally are of moderate strength and not often strong enough to be damaging.  The most destructive winds 
occur with "northeasters", tropical storms, and the occasional severe thunderstorms of the summer months.

The mean annual sunshine, though not unusually high at about 60% of the possible amount, is relatively constant 
with winter percentages only slightly lower than those of summer.  This is apparent in the comparatively large 
number of clear or partly cloudy days during the year.





DISCLAIMER
The data on this website has been compiled by Raymond C. Martin, Jr.
While the best attempt has been made to ensure accuracy, the data provided here CANNOT be guaranteed.
The National Climatic Data Center is the sole source of official climate data for the United States.

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