New Jersey State experiences a humid subtropical climate (Köppen Cfa, Cfb) in South Jersey, central and the northeast. The northwest portion has a humid continental climate (Köppen Dfa, Dfb) with cooler temperatures than the rest of the state. New Jersey lies on the eastern shore of the United States, halfway between the Equator and the North Pole. Delaware in the southwest, Pennsylvania in the west, New York in the north, and the Atlantic Ocean in the east and southeast share borders with the state. The distance from the Atlantic Ocean, and the prevailing westerly winds that flow from west to east influence the climate.
New Jersey, the Garden State, has an average elevation of 80 meters, with the highest elevation at High Point at 549 meters. There are five major geographical zones, with significant temperature differences between the south and the northwest. The Northern Zone covers one-fourth of the state and consists of highlands and valleys. The Central Zone runs from the Lower Hudson River to Trenton near the great bend of the Delaware River and experiences the heat island effect. Cold fronts in the highlands result in clouds when the rest of the state has clear skies. Pine Barrens with scrub pine and oak forests dominate the central south. The Southwest Zone has a maritime influence on the climate and lies between sea level and 30 meters above it. The Coastal Zone battles between continental and oceanic influences.
The average annual rainfall in New Jersey ranges from 40" (1016mm) in the southeast to 51" (1295.4mm) in the north and central parts. The precipitation occurs throughout the year with maxima in late spring and summer. The fall is the driest season with eight days per month of precipitation, while there are 120 wet days annually. The snowfall lasts from October to April, with 40" (1016mm) to 50" (1270mm) in the north, and 10" (254mm) to 15" (381mm) in the south. Freeze-free days range from 163 in the northern highlands to 217 along the coast. Frost arrives by October in much of the state, and occasionally by mid-September in the northern valleys. The average annual sunshine lasts from 2400 to 2800 hours.
Summer average temperatures in New Jersey usually range between 82°F (27.8°C) to 87°F (30.6°C). Central New Jersey tends to have 15 to 20 days of temperatures above 90°F (32.2°C), while the south registers double such number of days. Winters are severely cold in the northern highlands but relatively mild in the central and southern coastal areas. The average temperatures in the cold season are in the high 34°F (1.1°C) to 43°F (6.1°C) and low 16°F (-8.9°C) to 28°F (-2.2°C) ranges. The northwest registers lows below 0°F (-17.8°C), while the rest of the state occasionally drops below 10°F (-12.2°C). Spring and autumn seasons record wide variations in temperatures and are typically less humid than the summer.
The highest temperature on record in New Jersey is 110°F (43.3°C) on July 10, 1936, in Runyon, while the lowest recorded temperature is -34°F (-36.7°C) on January 5, 1904, in River Vale.
The best time to visit New Jersey
The best time to visit New Jersey is during late spring and early summer when the temperatures are mild. The period from April to June is warm, relatively dry, with a low likelihood of snow and storms. The humidity is bearable compared to the summer season. July is the height of summer, and the temperatures soar above 90°F (32.2°C) in many places. Early fall is another good time with a drop in temperatures and colorful landscapes. Summer coincides with the peak tourist season in New Jersey when everything from hotels to rentals becomes costly.
The worst time to visit New Jersey
The worst time to visit New Jersey is from December to February in the winter season. The conditions are cold and damp under the gloomy skies. Northwest New Jersey is severely cold, with temperatures dipping below 0°F (-17.8°C) in the night. Snowfall is heavy, and occasional blizzards make the conditions challenging. The coastal regions in the vicinity of the Atlantic Ocean are relatively warmer than the north. Winter is a treat for snow lovers with plenty of adventure and fun options available for selection. For the rest of the population, a vacation in the warm south of the United States is more appealing.
New Jersey is vulnerable to thunderstorms, floods, and snowstorms. Coastal storms called Nor' easters frequently occur between October and April. Storms range from 5 to 10, bring strong winds and heavy rains, and often raid several hundred miles offshore. Tornadoes are weak and number less than 5 in the year, but thunderstorms are in the range of 25 to 30 annually. Thunderstorms are prominent during late spring and summer and bring the majority of rainfall. Snowstorms typical of the North East frequently occur in the winter and stall daily life.
Weather in January
January is the peak of the winter season in New Jersey, with cold days and freezing nights. Trenton, the capital in the lower north, registers temperatures in the cold 23°F (-5°C) to 39°F (3.9°C), while Atlantic City in the south is a few degrees milder between 29°F (-1.7°C) to 42°F (5.6°C). Nights rarely rise above freezing, and occasionally even day temperatures are below the freezing mark. Although the coast is relatively warmer than the highlands, the ocean water is cold to the tune of 42°F (5.6°C) and unsuitable for swimming. The fishing season is a net gainer in the winter with plenty of lobsters and crabs for the taking in the high seas. The snowfall is in the range of 4" (101.6mm) to 8" (203.2mm) in the majority of the regions, with icy precipitation of 4" (101.6mm) to 5" (127mm) compounding the conditions. Expect the daily sunlight to last only for 5 hours and the daylight at its lowest of the year. January seldom attracts people to New Jersey except for business trips.
Weather in February
February is the snowiest month of the year in New Jersey, with occasional snowstorms in the fray. Newark and New Brunswick in the north, register snowfall in the range of 8" (203.2mm) to 10" (254mm), while it records between the 4" (101.6mm) to 7" (177.8mm) in the south. The precipitation of 5" (127mm) keeps the conditions wet for many days in the month. The average low temperatures are in the cold 17°F (-8.3°C) to 31°F (-0.6°C) zone, and the average high temperatures register between the 35°F (1.7°C) to 45°F (7.2°C) statewide. Sunny days are few, with the daily sunshine limited to 5 hours. The Nor' easters bring heavy rainfall and snow and cause damage in many areas. The highest snow depth of the year is advantageous for skiing, especially in the mountains. Expect black ice and slippery roads that see cars doing donuts even for experienced drivers. February is the time to wrap up in winter coats in New Jersey or sit by a crackling fire with a hot chocolate in hand.
Weather in March
March is cold and damp in New Jersey at the beginning of the spring season. The days are mild to warm, with the average temperatures in the 45°F (7.2°C) to 55°F (12.8°C) range. Nights are freezing for the better part of March and even significantly below freezing in North Jersey. The 3" (76.2mm) to 5" (127mm) of snow mainly falls in the north, especially in the northwest. The coastal regions see light snowfall at the most with an absence of snow cover. The daily sunshine lasts for 7 hours across the state, but the intensity of sunrays is moderate at best. The partly cloudy skies and the moist atmosphere is persistent in early spring even though the snow begins to thaw rapidly. An umbrella or a rain jacket is a useful accessory for early birds in New Jersey who wish to cash upon the early season discounts. March days alternate between rain and shine in New Jersey, with an odd storm making its way inland.
Weather in April
April is the period of singing birds and blooming flowers in New Jersey with the temperate weather of the spring season. The departure of the chilly winter enlightens the spirits with the spread of greenery on the landscape. The snowfall is light in the highlands by the fourth week of April. The snow cover is negligible in the remaining portion of the state. Shred any thoughts of losing rain jackets as the rain is a constant companion in New Jersey. However, there are extended periods of warm sunshine that total more than 7 hours a day. The average temperatures range between 36°F (2.2°C) during the night in the north to 64°F (17.8°C) during the day in the coastal south. Warm clothes keep any lingering cold at bay during the evenings and nights. Easter weather is enjoyable and sees a rise in tourist footfall in the state. April is an excellent time to be in New Jersey with the promise of warm weather on the cards.
Weather in May
May is the peak of the spring season in New Jersey with brilliant sunshine 244 hours in the month. Sunny days are back from the northern highlands to the southern coasts. The average high temperatures are in the warm 67°F (19.4°C) to 74°F (23.3°C), while the average low temperatures are in the mild zone of 46°F (7.8°C) to 55°F (12.8°C). High Point State Park has mild conditions and an absence of snow cover by the second half of May. Cape May is a popular tourist destination with average temperatures in the 50°F (10°C) to 73°F (22.8°C) range. The water in the cape is at a mild 53°F (11.7°C), and tourists begin to throng the nearby beaches and the warm sands by late spring. Although the snow is absent, the precipitation continues in the typical range of 3" (76.2mm) to 5" (127mm) statewide. Expect the temperatures to rise steadily by late spring. Beware of sudden rainstorms, and keep an eye on the weather in May in New Jersey.
Weather in June
June is the beginning of the warm to the hot summer season in New Jersey, with the average temperatures in the sunny 76°F (24.4°C) to 83°F (28.3°C) range. The days are long and bright, with moderate rain in the form of thunderstorms. Nights are cold and regularly below 56°F (13.3°C) in the northwest regions of Lambertville and Somerville. In South Jersey, the Belleplain State Forest is a popular tourist sport with temperatures in the zone of 76°F (24.4°C) to 83°F (28.3°C). The long days and 9 hours of daily sunshine keep the ocean waters mild. Crowds gather on the beaches and scale the heights of the wilderness in the forests and mountains. Hiking, trekking, biking, and camping are popular in the pleasant weather. The growing season is in advance stages with cranberries and blueberries ripe for the picking. Occasional tornadoes may cross the Atlantic shores and bring heavy rainfall inland. Keep an eye on the weather for thunderstorms in June in New Jersey.
Weather in July
July is usually the hottest month of the year in New Jersey, with average high temperatures in the 79°F (26.1°C) to 89°F (31.7°C). Moorestown in the south is one of the hottest places with temperatures in the 64°F (17.8°C) to 89°F (31.7°C) zone. New Jersey experiences many days with 95°F (35°C), and a few even touch the 100°F (37.8°C) mark and above in a typically hot year. The warm air of the Gulf Stream reaches the southern shores as the Atlantic High moves towards the north. The humidity is at a high in July, and the heat is often oppressive during mid-day. Sunglasses and sunscreen are beneficial, but it is better to skip the afternoon heat. The ocean temperatures reach up to 72°F (22.2°C) in July, and the waters attract the crowds. Thunderstorms bring the majority of the 4" (101.6mm) to 6" (152.4mm) of rainfall and are severe at times. Make use of mornings and evenings when the heat is bearable. July is the time of peak tourism in New Jersey.
Weather in August
August is a hot summer month in New Jersey, with the southern parts often registering more than 85°F (29.4°C). The average high temperatures are in the hot 77°F (25°C) to 87°F (30.6°C) zone, with sticky heat and partly cloudy skies. Sweatshirts and light summer clothing are the order of the day, with sunscreen and sunglasses mandatory on the beach. The mid-day sun, at its full intensity, reaches scorching levels in the summer. The vicinity of lake waters is an excellent idea to keep cool, and a fishing rod in hand makes the day enjoyable. August averages 3" (76.2mm) to 5" (127mm) of rainfall, with occasional storms in the air. The urban heat island effect is prominent in the central parts of New Jersey and results in a rise in temperatures by a few degrees. Light sweatshirts are usually sufficient during the day, while nights frequently need air-conditioners to beat the humidity. The end of August sees a steady dip in temperatures and humidity in New Jersey.
Weather in September
September is the period of the early autumn season in New Jersey that brings relief from the summer heat. The average high temperatures slide to the 70°F (21.1°C) to 80°F (26.7°C) range from the peak of summer. Nights are between 50°F (10°C) to 64°F (17.8°C) statewide and tend to be comfortable due to the decrease in humidity. The skies are partly cloudy with the precipitation in the 3" (76.2mm) to 5" (127mm) range. The peak season of storms is over, and the incidences of thunderstorms are low. Early fall is a beautiful time in New Jersey with a splash of colors all over the landscape. The northern highlands turn colors by the mid of September, and the hues progress rapidly to the south. A popular place to visit is the Delaware Gap during the calm days of autumn. Breezy evenings add to the pleasant atmosphere. Keep an eye on the weather for tropical cyclones that can interrupt vacations on the coast during September in New Jersey.
Weather in October
October brings peak fall foliage to New Jersey that it is breathtaking in the mountains and highlands of the northwest. The diverse landscape spreading the land and water assumes the nature of a wonderland out of a children's book. Plainfield and Long Branch in the north are in the range of 45°F (7.2°C) to 65°F (18.3°C), while Millville and Glassboro are between 44°F (6.7°C) to 66°F (18.9°C). The difference in temperatures between the northern and southern parts is at its lowest of the year. Fall is the driest period of the year, yet October receives 3" (76.2mm) to 4" (101.6mm) of rain. The sunlight lasts for 7 hours, and the days for 11 hours. Afternoons tend to be cloudy, while evenings are breezy. The best way to explore fall colors is by driving in the countryside or boating on the lake shores. Apple orchards and pumpkin patches abundantly dot the countryside as the harvest season draws to a close. The first flurries of snow invade New Jersey by the end of October.
Weather in November
November brings the end of the autumn in New Jersey as the temperatures drop rapidly in the state. The average high temperatures are in the mild 47°F (8.3°C) to 58°F (14.4°C) range, while the nights are chilly in the 30°F (-1.1°C) to 41°F (5°C) range. November sees snowfall in many places in the north, but the coastal regions remain untouched by ice. The fall colors are past their peak by the second week of November. Sunny days become increasingly rare as the sunlight lasts for a daily 5 hours. Add a rain jacket to the pack while exploring the colored landscape or the ocean waters. The day temperatures are comfortable, especially for budget travelers who wish to take advantage of the off-season discounts. The hunting and fishing season are still in full swing and attract considerable interest. Expect the cold to increase with each passing day in November, which is the last month of fair weather in New Jersey.
Weather in December
December is the darkest month in New Jersey as the daily sunshine lasts hardly for 4 hours. The beginning of the winter sees average high temperatures in the range of 36°F (2.2°C) to 47°F (8.3°C) and the average low temperatures in the freezing 21°F (-6.1°C) to 34°F (1.1°C) zone. The snowfall is moderate in the northwest and significant in the rest of the state. Icy precipitation, sleet, and snow keep people indoors most of the time. Warm winter coats are out of the closets along with boots, gloves, and caps. Fresh snow deposits are helpful for the lovers of skiing and snowmobiling, with snowmen standing everywhere during Christmas time. The frozen lake surfaces often double up as ice skating rinks as the landscape adorns a fairyland white color. The wind adds to the chilliness and brings down the temperatures rapidly as gloomy skies rule the roost. Expect the cold to increase further with each passing day in December.