Geography of New Jersey - Climate

Climate

Southern New Jersey has a humid subtropical climate while a humid continental climate (Microthermal Climate) prevails in the northwest, according to the Köppen climate classification. New Jersey's climate is vastly affected by its proximity to the Atlantic Ocean.

• Winter is typically cold. The lows usually hover in the 20s °F (down to -10 °C) and can frequently dip below 0 °F (−18 °C) in the northwestern sections of the state. New Jersey winters often feature snowstorms known as Nor'easters that can paralyze the area with over a foot of snow. However, a variation in the climate also occasionally renders winter mild and almost snowless in sections of South Jersey near the Atlantic coastline. In the Coastal and southern portions of the state, frequently precipitation falls as rain in the winter despite it snowing in the northwestern portion.

• Springs are mild, averaging in the 50s °F (10 to 15 °C) in late March to the lower 80s °F (25-30 °C) in early June. The weather is unpredictable and brings relatively cool summers as an occasional surprise, and huge snowstorms arriving as late as the second week in April (significant snow after mid-March is fairly rare though). Thunderstorms are common in spring.

• Summers in New Jersey tend to be hot and humid, with temperatures often exceeding 90 °F (32 °C), although high temperatures above 100 °F (38 °C) are uncommon. Humidity levels are usually quite high in July and August. Thunderstorms are common in summer. Hurricanes are considered to be a major threat to the area (and especially the Jersey Shoreline communities in Monmouth, Ocean, Atlantic and Cape May counties). While relatively infrequent compared to areas south and east, a direct hit could cause large loss of life and billions of dollars in damage due to the high population in coastal areas.

• Autumns are comfortable in New Jersey and similar to spring in temperature. However, the weather is notably unpredictable and travelers are advised to check forecasts and bring several layers of clothing in late fall and in the early spring months (e.g., November, March, April) as temperatures do fluctuate quickly at these times of year.

The temperatures vary greatly from the northernmost part of New Jersey to the southernmost part of New Jersey. For example, these are the average high and low temperatures for Cape May, near the state's southernmost ocean-facing point, Sussex, in the mountainous northwest, and Trenton, the state capital located roughly midway between the two: