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USDA Hardiness Zone 7b

Frost Dates for 11789 — Sound Beach, New York

NOAA 1991–2020 normals from Mt Sinai, NY (50 ft), 3 miles southwest.

Updated

In Sound Beach, the last spring frost (32°F) is around April 4 in half of years and has passed by April 19 in nine years out of ten. The first fall frost comes around November 7, as early as October 20 one year in ten, leaving a typical freeze-free season of 215 days (NOAA, Mt Sinai, NY).

Last spring frost
April 4

50% probability

First fall frost
November 7

50% probability

Growing season
215 days

freeze-free, 50%

Hardiness zone
7b

5 to 10°F (-15.0 to -12.2°C) coldest night

First snow
December 12

median, 1991–2020

Last snow
March 19

median, 1991–2020

Winters with snow
100%

27 of 27 observed

Snow per year
—

NOAA normal

Frost risk by date in Sound Beach

Half of springs at Mt Sinai, NY see their last 32°F night by April 4; only one in ten is past it by March 23, and one in ten still has one after April 19. Planting tender crops after April 10 leaves a 30% risk of a frost on them, after April 13 20%, and after April 19 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 29% of the 173 New York stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 7 in half of years, as early as October 20 one year in ten, and holds off past November 24 one year in ten. A hard freeze of 28°F follows 15 days later, around November 22; in spring the one-in-ten date for 28°F is April 7, 12 days before the 32°F one. The freeze-free season lasts 215 days in a typical year, longer than at 92% of the 173 New York stations; it reaches 236 days one year in ten and falls short of 195 one year in ten. On average 79 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 16 days longer, to about April 20, and return around October 26. Severe cold of 16°F or below comes in 99% of winters, usually between January 1 and February 25.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 6Apr 10Apr 14Apr 17Apr 20Apr 23Apr 27May 2May 7
32°FMar 23Mar 29Apr 1Apr 3Apr 4Apr 7Apr 10Apr 13Apr 19
28°FMar 11Mar 16Mar 20Mar 24Mar 27Mar 30Apr 1Apr 3Apr 7
24°FMar 1Mar 7Mar 11Mar 14Mar 16Mar 20Mar 23Mar 26Mar 31
20°FFeb 15Feb 25Mar 1Mar 5Mar 8Mar 11Mar 14Mar 18Mar 22
16°F99% of yrsJan 28Feb 6Feb 13Feb 20Feb 25Mar 1Mar 5Mar 9Mar 15
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FOct 10Oct 15Oct 18Oct 22Oct 26Oct 30Nov 2Nov 6Nov 10
32°FOct 20Oct 26Oct 30Nov 3Nov 7Nov 10Nov 14Nov 18Nov 24
28°FNov 2Nov 9Nov 14Nov 18Nov 22Nov 26Nov 30Dec 3Dec 9
24°FNov 18Nov 25Nov 30Dec 2Dec 6Dec 9Dec 13Dec 18Dec 24
20°FDec 1Dec 6Dec 10Dec 15Dec 19Dec 23Dec 27Jan 1Jan 8
16°F99% of yrsDec 10Dec 19Dec 25Dec 29Jan 1Jan 5Jan 10Jan 14Jan 22

Freeze probabilities 1991–2020 at Mt Sinai, NY, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.

Frost risk on any date in 11789 →Compare Sound Beach with another place →

Weather by month in Sound Beach

July is the warmest month at Mt Sinai, NY, averaging 83°F by day and 68°F at night; January is the coldest at 41°F and 26°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 70% of years.

Warmth for growing adds up to 3,534 growing degree days a year (base 50°F), more than at 96% of the 173 New York stations. 32% of them (1,129) have built up by the end of June, and July adds the most, 784.

Monthly normals 1991–2020 at Mt Sinai, NY
MonthHigh °FLow °F32°F nightNights ≤ 32°FGDD 50°F
Jan4126100%225
Feb4328100%197
Mar5033100%1524
Apr644370%3145
May72511%0359
Jun78610%0589
Jul83680%0784
Aug82670%0756
Sep75610%0540
Oct654932%<1237
Nov564094%673
Dec4632100%1417

Monthly normals 1991–2020 at Mt Sinai, NY (50 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.

Compared with the next station

The nearest other station, Setauket Strong, NY, 7 miles west of Sound Beach, has a last frost 11 days later (April 15), a first frost 3 days later (November 10), a season 7 days shorter.

Frost dates for 11790 (Stony Brook) →

When it snows in Sound Beach, New York

The first measurable snow (0.1 inch or more) in Sound Beach usually arrives around December 12, and the last of the season around March 19. Those are the middle dates across the winters of 1991–2020 at Upton Coop - Nwsfo New York, NY, 8.4 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 16 days after the last snow.

Planting calendar for 11789

What to do and when, from the 50% frost dates for Sound Beach, New York
WhenWhat to do
January 24 – February 7Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
February 7 – February 21Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
March 7 – March 21Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 4 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by August 15Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by October 24Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
November 7 onwardPlant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter.

The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.

Where these figures come from

ZIP 11789 is 3 miles from Mt Sinai, NY, which stands at 50 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 7 other ZIP codes share the station; its figures are presented in full for 11727 (Coram). The 2023 USDA Plant Hardiness Zone Map lists ZIP 11789 in zone 7b, the band where the coldest night of the year averaged 5 to 10°F (-15.0 to -12.2°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across New York →

Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.

Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.

ZIP codes measured at the same station

Other zone 7b places in New York