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Shaded-relief map of South Valley Stream, New York: rivers, roads, the city limits and where the water drains.
NEW YORK · NASSAU COUNTY

South Valley Stream

6,386 people, 20 ft above sea level in Nassau County.

20 ftElevation, city center
6,386People, 2024 estimate
1 sq miLand area
Mostly cloudy 44°
Mostly cloudy now Dew point 32° · WNW 12 mph · high 44°
City of South Valley Stream River Interstate 2 miles
Explore the plate Order a print

The South Valley Stream plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.

MILE1
TODAY

Today in South Valley Stream

NWS forecast and National Blend of Models · updated 7:00 PM EST
RIGHT NOW Kennedy International Airport (KJFK) · 7:51 PM
Mostly cloudy
44° Mostly cloudy Feels like 38° · high of 44° near 8 PM
WindWNW 12 mphgusts 24
Humidity62%rising to 70% by morning
Pressure29.89 in →steady
Visibility10 mihaze-free
CloudsBrokenbases near 5,000 ft
UV index—no forecast
Dew point 32° · Dryabout the same for three days
DryComfortableStickyMuggyOppressive
NEXT RAIN
Clear
Not this weeknone in the forecast for a week
LIKELY AMOUNT—nothing expected
LAST RAINNov. 130.41 in · 1 dry day
ALERTS & OUTLOOKS
No watches or warnings for Nassau County
NWS Upton and the Storm Prediction Center · checked 8:47 PM
SUN & MOON
↑ 6:40 AM4:38 PM ↓
9 h 58 m of daylight, 2 minutes less than yesterday
Waxing crescent, 27% lit. Next full moon: Nov. 24.
AIR & POLLEN
21
GOODAir quality index · ozone
Tomorrow: 18, good. No pollen source yet.

The next three days, hour by hour

Sky: clear, cloudy, night Rain likely National Blend of Models
SATURDAY, NOV. 14
SUNDAY, NOV. 15
MONDAY, NOV. 16
TUESDAY, NOV. 17
8p
11p
2a
5a
8a
11a
2p
5p
8p
11p
2a
5a
8a
11a
2p
5p
8p
11p
2a
5a
8a
11a
2p
5p
partly cloudy night
partly cloudy night
mostly clear night
clear night
clear day
mostly sunny
partly cloudy day
partly cloudy night
mostly clear night
mostly clear night
clear night
mostly clear night
mostly sunny
partly cloudy day
partly cloudy day
partly cloudy night
mostly clear night
mostly clear night
mostly clear night
mostly clear night
mostly sunny
clear day
clear day
clear night
TEMPERATURE °F
44°
41°
52°
39°
52°
40°
55°
CHANCE OF RAIN
50%
WIND, MPH
15
15
14
15
15
16
16
14
11
10
8
8
10
11
11
10
8
7
7
7
7
8
9
10
HOW IT FEELS · DEW POINT
Dry: dew points 28 to 38°

The next seven days, and how sure we are

Forecast, with the range 8 in 10 ensemble members agree on Normal, about 54° / 40°
SAT Nov. 14 Partly cloudy Partly cloudy
44° 39°
10% rain — WNW 15 A
SUN Nov. 15 Mostly sunny; warmer Mostly sunny; warmer
52° 37°
0% rain — NW 16 A
MON Nov. 16 Partly cloudy Partly cloudy
53° 38°
0% rain — NW 10 A
TUE Nov. 17 Sunny Sunny
57° 41°
0% rain — WNW 10 A
WED Nov. 18 Sunny Sunny
61° 43°
0% rain — W 8 A
THU Nov. 19 Mostly sunny Mostly sunny
61° 45°
0% rain — WSW 8 A
FRI Nov. 20 Mostly sunny Mostly sunny
62° 46°
0% rain — NW 7 A
How sure are we? AModels agree: highs within 4° BSome spread: within 8° CWide spread: check back
Range from the National Blend of Models percentiles · graded on Forecast Scores
AIR MAIL

Where today’s air came from

The air arriving over South Valley Stream about 5,000 feet above the ground was over the Canadian Prairies three days ago, and over the Great Lakes a day ago, about 2,310 miles back along its path. Near the ground the air came from the Canadian Prairies; at 10,000 feet, from the Gulf of Alaska. It feels dry all the same. Traced back 72 hours through NOAA’s hourly RAP analyses and the GFS beyond them, nine paths at each of three heights.

THIS WEEK IN 1993 Nov. 15, 1993

The hottest this week has been

77° on Nov. 15, 1993, the hottest reading for this week of the year since 1948. Next is 72° in 2001.

72°
77°
20011993
Source: NOAA RCC-ACIS, the New York-Kennedy Airport Area threaded record since 1948.
MILE2
THE GROUND

What South Valley Stream stands on

South Valley Stream’s center stands about 20 ft above sea level. Within three miles the land runs from 0 ft to 70 ft, a difference of 70 ft: gently rolling country. The highest named summit within 15 miles is Harbor Hill, about 380 ft, 11 miles north-northeast.

Under the town center the state geologic map shows Monmouth Group, Matawan Group and Magothy Formation (clay, sand, gravel), from the Late Cretaceous, 66 to 100 million years old.

South Valley Stream, cut in half from southwest to northeast

A section southwest to northeast, 24 miles through the town center
0 ft100 ft200 ft300 ft SOUTH VALLEY STREAM20 ftElmont60 ftHarbor Hill380 ft ← SWGreenvale · NE →

Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 54×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.

Rock at the surface along the line

Monmouth Group, Matawan Group and Magothy Formation

Clay, sand, gravel. Age: Late Cretaceous, 66 to 100 million years old. About 17 mi of the line.

From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.

Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.

MILE3
THE WATER

Where South Valley Stream’s rain goes

A raindrop that lands in South Valley Stream reaches New York Harbor and the Atlantic Ocean by way of the Valley Stream and Hook Creek: about 3 river miles.

THE WAY DOWN, TO SCALE
South Valley Stream≈ 3 mi · New York Harbor and the Atlantic Ocean
FROM THE CENTER OF SOUTH VALLEY STREAM ≈ 3 mi to New York Harbor and the Atlantic Ocean Valley Stream → Hook Creek

Traced down the USGS NHDPlus V2.1 river network from the Census center point of South Valley Stream; river miles along the main stem, rounded.

MILE5
THE ALMANAC

South Valley Stream’s year

1991–2020 normals · records since 1948 · Jfk International Airport, 3 mi west-southwest

South Valley Stream has a humid subtropical climate. Summer afternoons average 84° in July; winter nights fall to about 26° in January. A normal year brings about 26 inches of snow; with the rain, that comes to about 43 inches of water.

39°26°42°28°49°34°59°43°68°53°78°62°84°69°82°68°76°61°65°50°54°40°44°32° JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 12 TODAY 43.3 in rain and snowmelt
Normal high to low, by month Record high to low, by day Rain by month Freezing
July, average84° / 69°high / low, the warmest month
January, average39° / 26°high / low, the coldest month
Rain and melted snow43.3 inwettest months: August and December
Snow a year25.9 insnowiest: February
Hottest on record104°FJuly 3, 1966
Coldest on record−2°FJanuary 21, 1985
Wettest day on record8.05 inSeptember 29, 2023
Snowiest day on record30.3 inJanuary 23, 2016
90° days a year11very few reach 100°
Nights at or below 32°74and 14 days that stay below freezing
Climate typeHumid subtropicalKöppen Cfa

AROUND THE RING

1Freeze seasonfrom the first fall freeze, about Nov. 15, to the last in spring, about April 2 (median dates)
2Lows below freezingDec. 14 to March 12; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 South Valley Stream normally reaches 54° and falls to 40°. The record high is 68°, in 2005; the record low 24°, in 2019. The most rain on this date, 1.91 in, fell in 1972.

MONTH BY MONTH
JanFebMarAprMayJunJulAugSepOctNovDec
Normal high39°42°49°59°68°78°84°82°76°65°54°44°
Normal low26°28°34°43°53°62°69°68°61°50°40°32°
Rain and melt, in3.232.763.943.553.663.853.864.113.583.723.073.96
Snow, inches7.58.64.30.60.00.00.00.00.00.00.44.5
Record high71° (2007)71° (1997)85° (1990)90° (2002)99° (1969)102° (2025)104° (1966)101° (1948)98° (1983)95° (2019)82° (2024)75° (1998)
Record low−2° (1985)−2° (1963)7° (1967)20° (1982)34° (2020)45° (1967)55° (1979)46° (1965)40° (1963)30° (1976)15° (2018)2° (1983)

Normals 1991–2020 and records since 1948 from the New York-Kennedy Airport Area threaded record (Jfk International Airport, 3 miles west-southwest). NOAA, through RCC-ACIS.

MILE7
ON THE NETWORK

Around South Valley Stream on the Forecast Network

Neighboring plates

New York NY · 12 MI 12 miles west Newark NJ · 24 MI 24 miles west Bridgeport CT · 46 MI 46 miles northeast Philadelphia PA · 87 MI 87 miles southwest Springfield MA · 118 MI 118 miles northeast Providence RI · 144 MI 144 miles northeast
FORECASTCITY
Map of South Valley Stream, New York. Explore the plate
NEW YORK · NASSAU

South Valley Stream

6,386 people, 20 ft above sea level in Nassau County.

20 ftElevation
6,386People
1 sq miLand
Mostly cloudy 44°
Mostly cloudyDew point 32°
1

Today in South Valley Stream

NEXT 15 HOURS
Now partly cloudy night 44° 1%
11p partly cloudy night 43° 5%
2a partly cloudy night 42° 2%
5a mostly clear night 42° 1%
8a clear day 45° 0%
11a mostly sunny 50° 1%
Clear
NEXT RAINNone this week
→
Sat10%
Partly cloudy Partly cloudy
39
44
A
Sun0%
Mostly sunny; warmer Mostly sunny; warmer
37
52
A
Mon0%
Partly cloudy Partly cloudy
38
53
A
Tue0%
Sunny Sunny
41
57
A
Wed0%
Sunny Sunny
43
61
A
Thu0%
Mostly sunny Mostly sunny
45
61
A
Fri0%
Mostly sunny Mostly sunny
46
62
A
Letters show how sure the forecast is: A, models agree; B, some spread; C, check back. Sample data.
THIS WEEK IN 1993 · NOV. 15, 1993

77°, the hottest this week of the year has been since 1948.

2

What South Valley Stream stands on

South Valley Stream’s center stands about 20 ft above sea level. Within three miles the land runs from 0 ft to 70 ft, a difference of 70 ft: gently rolling country. The highest named summit within 15 miles is Harbor Hill, about 380 ft, 11 miles north-northeast.

South Valley Stream, southwest to northeast South Valley Stream20 ft ← SWNE → 24 miles through the town center; vertical exaggeration about 103×. Colors: rock at the surface.
Elevation, center20 ft
Within 3 miles0 to 70 ft
Lie of the landGently rolling (70 ft of relief)
High point nearbyHarbor Hill, 380 ft, 11 mi north-northeast
Rock at the surfaceMonmouth Group, Matawan Group and Magothy Formation
Its ageLate Cretaceous, 66 to 100 million years old
5

South Valley Stream’s year

South Valley Stream has a humid subtropical climate. Summer afternoons average 84° in July; winter nights fall to about 26° in January. A normal year brings about 26 inches of snow; with the rain, that comes to about 43 inches of water.

JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 12 43.3 in
July, average84° / 69° · high / low, the warmest month
January, average39° / 26° · high / low, the coldest month
Rain and melted snow43.3 in · wettest months: August and December
Snow a year25.9 in · snowiest: February
Hottest on record104°F · July 3, 1966
Coldest on record−2°F · January 21, 1985
Wettest day on record8.05 in · September 29, 2023
Snowiest day on record30.3 in · January 23, 2016
90° days a year11 · very few reach 100°
Nights at or below 32°74 · and 14 days that stay below freezing
Climate typeHumid subtropical · Köppen Cfa
1Freeze season · from the first fall freeze, about Nov. 15, to the last in spring, about April 2 (median dates)
2Lows below freezing · Dec. 14 to March 12; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 South Valley Stream normally reaches 54° and falls to 40°. The record high is 68°, in 2005; the record low 24°, in 2019. The most rain on this date, 1.91 in, fell in 1972.

Normals 1991–2020 and records since 1948 from the New York-Kennedy Airport Area threaded record (Jfk International Airport, 3 miles west-southwest). NOAA, through RCC-ACIS.
3

Where the rain goes

≈ 3 mito the AtlanticValley Stream → Hook Creek

A raindrop that lands in South Valley Stream reaches New York Harbor and the Atlantic Ocean by way of the Valley Stream and Hook Creek: about 3 river miles.