Frost dates for Somerville Somerset Airport, New Jersey
Half of years have their last spring frost by April 26, but 1 year in 10 still frosts after May 13.
A frost date is really a percentile from 30 years of records at a nearby weather station: in about half of years a frost still comes after the median date. Both numbers are below, so you can choose the risk yourself.
The odds
Last spring frost
How often a frost still comes on or after each date.
- 1 year in 10
- May 13
- 1 year in 5
- May 7
- 3 years in 10
- May 2
- 2 years in 5
- April 29
- Half of years (the median)
- April 26
First fall freeze
How often the first freeze comes on or before each date.
- 1 year in 10
- October 5
- 1 year in 5
- October 9
- 3 years in 10
- October 12
- 2 years in 5
- October 15
- Half of years (the median)
- October 18
- Growing season
- about 176 days
- Hardiness zones nearby
- 6b, 7a
- Summer days
- a usual high of about 29 °C84 °F
- Lettuce and spinach run to seed
- June to September, in hot, long days (how we know)
Summer and rain
A growing garden needs about 25 mm1 in of water a week, rain and watering together. Here is what a normal month brings.
Month by month
- January
- high ~4 °C39 °F · low ~-6 °C21 °F · rain ~80 mm3.2 in
- February
- high ~6 °C43 °F · low ~-5 °C22 °F · rain ~56 mm2.2 in
- March
- high ~10 °C51 °F · low ~-1 °C29 °F · rain ~99 mm3.9 in
- April
- high ~17 °C63 °F · low ~4 °C39 °F · rain ~91 mm3.6 in
- May
- high ~23 °C73 °F · low ~9 °C48 °F · rain ~90 mm3.5 in
- June
- high ~27 °C81 °F · low ~14 °C58 °F · rain ~107 mm4.2 in
- July
- high ~30 °C86 °F · low ~17 °C63 °F · rain ~125 mm4.9 in
- August
- high ~29 °C84 °F · low ~16 °C61 °F · rain ~132 mm5.2 in
- September
- high ~25 °C78 °F · low ~12 °C54 °F · rain ~97 mm3.8 in
- October
- high ~19 °C66 °F · low ~6 °C42 °F · rain ~93 mm3.7 in
- November
- high ~13 °C55 °F · low ~0 °C33 °F · rain ~87 mm3.4 in
- December
- high ~7 °C44 °F · low ~-3 °C26 °F · rain ~98 mm3.9 in
Where these numbers come from
NOAA NCEI 1991–2020 Climate Normals, the Somerville Somerset Airport station (listed by NOAA as Somerville Somerset Ap, USW00054785), at 40.62, -74.67. These are that station’s own records, unshifted. The further your garden is from it, the less exactly they describe your ground. The planner finds the nearest station to your garden and lowers its confidence with distance, so no number is presented as if it were measured in your garden.
Cold air also pools in low ground on the clear, still nights when frost happens, so a hollow can freeze while a slope a few hundred feet away does not. No table can know that about your garden. A few seasons of your own logged frosts can.
ZIP codes nearest this station
07828, 07830, 07836, 07840, 07853, 07865, 07870, 07920, 07921, 07924, 07930, 07931…
+25 moreShow fewer
07934, 07939, 07945, 07977, 07979, 08502, 08801, 08807, 08809, 08821, 08822, 08823, 08826, 08829, 08833, 08835, 08836, 08844, 08853, 08858, 08869, 08876, 08887, 08889, 08890.
Nearby stations
The nearest stations and how their last-frost dates compare. Together they show how frost varies across your area.
- Plainfield, NJ, last frost by April 11
- Boonton 1 SE, NJ, last frost by April 17
- Trenton State College, NJ, last frost by April 17
- Phillipsburg-Easton Brg, NJ, last frost by April 18
- Harrison, NJ, last frost by April 4
- Freehold-Marlboro, NJ, last frost by April 17
Other stations in New Jersey.
- Wanaque Raymond Dam, NJ, last frost by April 19
- Teterboro Airport, NJ, last frost by April 3
- Sussex 3 WNW, NJ, last frost by April 30
- Long Branch-Oakhurst, NJ, last frost by April 9
- Indian Mills 2 W, NJ, last frost by April 28
- Millville Municipal Airport, NJ, last frost by April 24
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