Andover, New Jersey climate: Normal weather by month, frost dates and records
Andover's normal year runs from 19°F January nights to 84°F July afternoons, with 48.8 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.3°C, January lows of −7°C, July highs of 29°C, 1,240 mm of precipitation a year.
- NOAA stationAndover Aeroflex Airport
- Station IDUSW00054779
- Location41.01°N 74.74°W
- Elevation583 ft (178 m)
- From the center2 miles
- Population610
On October 14, the normal high in Andover is 64°F and the normal low 42°F, and the chance of measurable rain or snow is 37%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Andover.
- Jan 36° 19°
- Feb 39° 20°
- Mar 48° 28°
- Apr 61° 38°
- May 71° 48°
- Jun 79° 57°
- Jul 84° 62°
- Aug 82° 60°
- Sep 74° 52°
- Oct 63° 42°
- Nov 52° 32°
- Dec 41° 25°
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 Andover each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 19°F. The most precipitation falls in July (5.06 in), the least in February (2.83 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 36°F | 19°F | 27.4°F | 3.27 | 12 | <1 | 28 | 9 h 30 min |
| February | 39°F | 20°F | 29.4°F | 2.83 | 11 | <1 | 26 | 10 h 40 min |
| March | 48°F | 28°F | 37.8°F | 4.07 | 11 | <1 | 22 | 11 h 50 min |
| April | 61°F | 38°F | 49.5°F | 3.78 | 12 | <1 | 7 | 13 h 20 min |
| May | 71°F | 48°F | 59.5°F | 3.83 | 13 | 1 | <1 | 14 h 30 min |
| June | 79°F | 57°F | 68.1°F | 4.54 | 14 | 2 | <1 | 15 h 10 min |
| July | 84°F | 62°F | 72.7°F | 5.06 | 13 | 6 | <1 | 14 h 50 min |
| August | 82°F | 60°F | 70.8°F | 4.85 | 12 | 3 | <1 | 13 h 50 min |
| September | 74°F | 52°F | 63.4°F | 4.32 | 11 | 1 | <1 | 12 h 30 min |
| October | 63°F | 42°F | 52.3°F | 4.64 | 11 | <1 | 4 | 11 h 10 min |
| November | 52°F | 32°F | 42.0°F | 3.43 | 10 | <1 | 16 | 10 h |
| December | 41°F | 25°F | 32.8°F | 4.18 | 12 | <1 | 25 | 9 h 20 min |
| Year (annual) | 61°F | 40°F | 50.5°F | 48.80 | 144 | 11 | 127 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 2°C | −7°C | −2.6°C | 83 mm |
| February | 4°C | −7°C | −1.4°C | 72 mm |
| March | 9°C | −2°C | 3.2°C | 103 mm |
| April | 16°C | 3°C | 9.7°C | 96 mm |
| May | 22°C | 9°C | 15.3°C | 97 mm |
| June | 26°C | 14°C | 20.1°C | 115 mm |
| July | 29°C | 17°C | 22.6°C | 129 mm |
| August | 28°C | 16°C | 21.6°C | 123 mm |
| September | 24°C | 11°C | 17.4°C | 110 mm |
| October | 17°C | 5°C | 11.3°C | 118 mm |
| November | 11°C | 0°C | 5.6°C | 87 mm |
| December | 5°C | −4°C | 0.4°C | 106 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Sussex (3 mi WNW) (15 miles away), gets 39 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054779; 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 Andover?
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 (11).
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 USW00054779.
When is the last frost in Andover?
In Andover, the last spring frost (32°F) comes after April 25 in half of years and after May 11 in one year in ten; the first autumn frost comes before October 19 in half of years and before October 5 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
- April 251 year in 10 after May 11; 9 in 10 after April 12
- First autumn frost, half of years before
- October 191 year in 10 before October 5; 9 in 10 before November 3
NOAA puts the median frost-free season at 175 days, and the season without a hard freeze (28°F) at 202 days.
A hard freeze (28°F) comes after April 11 in half of springs and before October 31 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Andover in zone 6b in ZIP code 07821, the nearest ZIP area.
Frost dates for every NOAA station in New Jersey · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00054779; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. 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 Andover?
In a normal year in Andover, 11 days a year reach 90°F, 127 nights fall to 32°F or colder and 144 days bring measurable precipitation.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 127a normal year
- Days that stay below freezing
- 27high of 32°F or less
- Days with 0.01 inch of precipitation
- 144a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USW00054779.
How sunny is Andover?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Andover, 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 Andover need?
A normal year in Andover brings 5,927 heating degree days, 10% more than the median U.S. place (5,373), and 669 cooling degree days, 26% 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 2,877 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,165 | 0 |
| February | 997 | 0 |
| March | 842 | 0 |
| April | 470 | 5 |
| May | 205 | 34 |
| June | 38 | 130 |
| July | 4 | 243 |
| August | 11 | 191 |
| September | 108 | 60 |
| October | 400 | 6 |
| November | 690 | 0 |
| December | 998 | 0 |
| Year (annual) | 5,927 | 669 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054779. 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 Andover been warmer than normal lately?
2021 averaged 53.4°F, 2.9°F above the 1991-2020 normal of 50.5°F.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 53.4°F | +2.9°F | 54.24 |
Source: observed years: ACIS, station USW00054779. A year counts only with all twelve months complete.
How does Andover's climate compare?
Andover is warmer than 3 of the other 32 places with their own NOAA record in New Jersey, and wetter than 18. Across the 7,247 U.S. stations with normals, its annual mean of 50.5°F is warmer than 43%.
In the Köppen classification computed from these normals, Andover 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 Andover share this climate record?
19 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.
- Hopatcong, NJ14,750 people · 6 mi SE
- Lake Hopatcong, NJ10,383 people · 7 mi SE
- Hackettstown, NJ10,182 people · 12 mi SW
- Budd Lake, NJ10,106 people · 9 mi S
- Succasunna, NJ9,866 people · 11 mi S
- Lake Mohawk, NJ9,116 people · 3 mi E
- Flanders, NJ8,949 people · 12 mi S
- Mount Arlington, NJ5,979 people · 8 mi SE
- Ledgewood, NJ5,150 people · 9 mi S
- Panther Valley, NJ4,622 people · 9 mi SW
- Landing, NJ4,499 people · 8 mi SE
- Netcong, NJ3,925 people · 8 mi S
- Stanhope, NJ3,599 people · 7 mi S
- Byram Center, NJ2,018 people · 5 mi S
- Kenvil, NJ1,719 people · 11 mi SE
- Port Morris, NJ1,141 people · 8 mi S
- Lower Berkshire Valley, NJ532 people · 9 mi SE
- Johnsonburg, NJ425 people · 8 mi SW
- Allamuchy, NJ107 people · 7 mi SW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Andover's climate
What is the coldest month in Andover?
January, with a normal high of 36°F and a normal low of 19°F. The warmest is July (84°F by day, 62°F at night).
Does it snow in Andover?
Yes. NOAA publishes no 1991-2020 snowfall normal for Andover's NOAA station; the nearest record that keeps one, Sussex (3 mi WNW) (15 miles away), records 39 inches of snow in a normal year.
What is the rainiest month in Andover?
July, with 5.06 in of precipitation in a normal year; the driest is February with 2.83 in.
What plant hardiness zone is Andover in?
The USDA's 2023 map puts Andover in zone 6b in ZIP code 07821, the nearest ZIP area.
How late can frost come in Andover?
In half of years the last 32°F night comes after April 25; in one year in ten it comes after May 11. Waiting until May 11 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, NJ3 miles from this station, 50.4°F a year
- Sussex, NJ14 miles from this station, 50.1°F a year
- Charlotteburg Reservoir, NJ16 miles from this station, 50.0°F a year
- Boonton, NJ19 miles from this station, 51.8°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made