Sussex, New Jersey climate: Normal weather by month, frost dates and records
Sussex's normal year runs from 18°F January nights to 84°F July afternoons, with 41.0 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.1°C, January lows of −8°C, July highs of 29°C, 1,040 mm of precipitation a year.
- NOAA stationSussex Airport
- Station IDUSW00054793
- Location41.20°N 74.62°W
- Elevation421 ft (128 m)
- Population2,072
On October 14, the normal high in Sussex is 64°F and the normal low 41°F, and the chance of measurable rain or snow is 39%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Sussex.
- Jan 36° 18°
- Feb 39° 20°
- Mar 48° 27°
- Apr 61° 37°
- May 71° 47°
- Jun 80° 56°
- Jul 84° 61°
- Aug 82° 60°
- Sep 75° 51°
- Oct 64° 40°
- Nov 51° 31°
- Dec 41° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Sussex each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 18°F. The most precipitation falls in October (4.23 in), the least in February (2.16 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 36°F | 18°F | 27.0°F | 2.63 | 11 | <1 | 28 | 9 h 30 min |
| February | 39°F | 20°F | 29.4°F | 2.16 | 10 | <1 | 25 | 10 h 40 min |
| March | 48°F | 27°F | 37.5°F | 3.20 | 12 | <1 | 22 | 11 h 50 min |
| April | 61°F | 37°F | 48.8°F | 3.43 | 12 | <1 | 10 | 13 h 20 min |
| May | 71°F | 47°F | 59.2°F | 3.73 | 14 | 1 | 1 | 14 h 30 min |
| June | 80°F | 56°F | 67.7°F | 3.68 | 14 | 2 | <1 | 15 h 10 min |
| July | 84°F | 61°F | 72.2°F | 4.06 | 15 | 5 | <1 | 14 h 50 min |
| August | 82°F | 60°F | 70.8°F | 3.93 | 16 | 3 | <1 | 13 h 50 min |
| September | 75°F | 51°F | 62.7°F | 3.83 | 14 | 1 | <1 | 12 h 30 min |
| October | 64°F | 40°F | 51.9°F | 4.23 | 11 | <1 | 6 | 11 h 10 min |
| November | 51°F | 31°F | 41.2°F | 2.97 | 10 | <1 | 17 | 10 h |
| December | 41°F | 24°F | 32.3°F | 3.10 | 11 | <1 | 26 | 9 h 10 min |
| Year (annual) | 61°F | 39°F | 50.1°F | 40.95 | 150 | 12 | 135 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 2°C | −8°C | −2.8°C | 67 mm |
| February | 4°C | −7°C | −1.4°C | 55 mm |
| March | 9°C | −3°C | 3.1°C | 81 mm |
| April | 16°C | 3°C | 9.3°C | 87 mm |
| May | 22°C | 8°C | 15.1°C | 95 mm |
| June | 26°C | 13°C | 19.8°C | 93 mm |
| July | 29°C | 16°C | 22.3°C | 103 mm |
| August | 28°C | 15°C | 21.6°C | 100 mm |
| September | 24°C | 11°C | 17.1°C | 97 mm |
| October | 18°C | 5°C | 11.1°C | 107 mm |
| November | 11°C | −1°C | 5.1°C | 75 mm |
| December | 5°C | −5°C | 0.2°C | 79 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Sussex's own co-op station Sussex (3 mi WNW) does: 39 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054793; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Sussex?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, September has the fewest days with rain (14).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054793.
When is the last frost in Sussex?
In Sussex, the last spring frost (32°F) comes after May 1 in half of years and after May 18 in one year in ten; the first autumn frost comes before October 12 in half of years and before September 30 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 11 year in 10 after May 18; 9 in 10 after April 19
- First autumn frost, half of years before
- October 121 year in 10 before September 30; 9 in 10 before October 28
NOAA puts the median frost-free season at 164 days, and the season without a hard freeze (28°F) at 188 days.
A hard freeze (28°F) comes after April 19 in half of springs and before October 25 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Sussex in zone 6b in ZIP code 07461, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Sussex's NOAA station is in zone 6a: the coldest night of a typical year reaches −5°F (20 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in New Jersey · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00054793; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Sussex?
In a normal year in Sussex, 12 days a year reach 90°F, 135 nights fall to 32°F or colder and 150 days bring measurable precipitation.
- Days at 90°F or more
- 12a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 135a normal year
- Days that stay below freezing
- 26high of 32°F or less
- Days with 0.01 inch of precipitation
- 150a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USW00054793.
How sunny is Sussex?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Sussex, 3.8 kWh per square metre a day. July is the sunniest month (78%) and December the cloudiest (61%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 65% | 1.8 |
| February | 67% | 2.6 |
| March | 67% | 3.6 |
| April | 68% | 4.6 |
| May | 68% | 5.3 |
| June | 72% | 5.8 |
| July | 78% | 5.9 |
| August | 76% | 5.1 |
| September | 75% | 4.2 |
| October | 68% | 2.8 |
| November | 68% | 2.0 |
| December | 61% | 1.4 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Sussex need?
A normal year in Sussex brings 6,048 heating degree days, 13% more than the median U.S. place (5,373), and 639 cooling degree days, 30% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,806 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,178 | 0 |
| February | 995 | 0 |
| March | 853 | 0 |
| April | 491 | 5 |
| May | 210 | 32 |
| June | 41 | 121 |
| July | 5 | 230 |
| August | 11 | 191 |
| September | 123 | 55 |
| October | 412 | 6 |
| November | 716 | 0 |
| December | 1,014 | 0 |
| Year (annual) | 6,048 | 639 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054793. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Sussex been warmer than normal lately?
2025 averaged 51.5°F, 1.4°F above the 1991-2020 normal of 50.1°F. 3 of the 3 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 52.3°F | +2.1°F | – |
| 2024 | 53.2°F | +3.1°F | 40.70 |
| 2025 | 51.5°F | +1.4°F | – |
Source: observed years: ACIS, station USW00054793. A year counts only with all twelve months complete.
How does Sussex's climate compare?
Sussex is warmer than 0 of the other 32 places with their own NOAA record in New Jersey, and wetter than 0. Across the 7,247 U.S. stations with normals, its annual mean of 50.1°F is warmer than 40%.
In the Köppen classification computed from these normals, Sussex is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Sussex share this climate record?
8 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Warwick, NY6,546 people · 14 mi E
- Franklin, NJ5,059 people · 7 mi S
- Highland Lakes, NJ3,941 people · 9 mi E
- Hamburg, NJ3,351 people · 4 mi SE
- Florida, NY2,868 people · 17 mi NE
- Ogdensburg, NJ2,310 people · 8 mi S
- Vernon Center, NJ1,490 people · 6 mi E
- Unionville, NY632 people · 8 mi NE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Sussex's other NOAA stations record?
2 more NOAA stations keep 1991-2020 normals in or near Sussex. This page uses Sussex Airport; the others differ by site and elevation:
| Station | From this station | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Sussex (3 mi WNW) USC00288644 | 3 mi NW | 667 ft | 49.2°F | 17°F | 83°F | 48.7 | 39 | April 30 |
| Sussex (8 mi NNW) USC00288648 | 9 mi N | 1,020 ft | 49.6°F | 18°F | 82°F | – | – | April 20 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Sussex's climate
What is the coldest month in Sussex?
January, with a normal high of 36°F and a normal low of 18°F. The warmest is July (84°F by day, 61°F at night).
Does it snow in Sussex?
Yes. NOAA publishes no 1991-2020 snowfall normal for Sussex's NOAA station; Sussex's own co-op station Sussex (3 mi WNW) records 39 inches of snow in a normal year.
What is the rainiest month in Sussex?
October, with 4.23 in of precipitation in a normal year; the driest is February with 2.16 in.
What plant hardiness zone is Sussex in?
The USDA's 2023 map puts Sussex in zone 6b in ZIP code 07461, the nearest ZIP area. By the same method at Sussex's NOAA station, the coldest night of a typical year reaches −5°F (20 years, 1991-2020): zone 6a.
How late can frost come in Sussex?
In half of years the last 32°F night comes after May 1; in one year in ten it comes after May 18. Waiting until May 18 leaves about a one-in-ten chance of a later frost.
Nearby and next
- New Jersey climateThe statewide normals and every place in the state
- Newton, NJ12 miles from this station, 50.4°F a year
- Port Jervis, NY14 miles from this station, 48.8°F a year
- Matamoras, PA14 miles from this station, 48.3°F a year
- Andover, NJ14 miles from this station, 50.5°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made