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Shaded-relief map of Mount Sinai, New York: rivers, roads, the city limits and where the water drains.
NEW YORK · SUFFOLK COUNTY

Mount Sinai

11,623 people, 80 ft above sea level in Suffolk County.

80 ftElevation, city center
11,623People, 2024 estimate
6 sq miLand area
Clear 43°
Clear now Dew point 31° · WNW 9 mph · high 40°
City of Mount Sinai River Interstate 2 miles
Explore the plate Order a print

The Mount Sinai 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 Mount Sinai

NWS forecast and National Blend of Models · updated 7:00 PM EST
RIGHT NOW Long Island Mac Arthur Airport (KISP) · 7:56 PM
Clear
43° Clear Feels like 38° · high of 40° near 8 PM
WindWNW 9 mphno gusts
Humidity62%rising to 82% by morning
Pressure29.84 in →steady
Visibility10 mihaze-free
CloudsClear
UV index—no forecast
Dew point 31° · 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. 130.12 in · 1 dry day
ALERTS & OUTLOOKS
No watches or warnings for Suffolk County
NWS Upton and the Storm Prediction Center · checked 8:46 PM
SUN & MOON
↑ 6:38 AM4:35 PM ↓
9 h 56 m of daylight, 2 minutes less than yesterday
Waxing crescent, 27% lit. Next full moon: Nov. 24.
AIR & POLLEN
65
MODERATEAir quality index · coarse particles
Tomorrow: 22, 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
partly cloudy night
mostly clear night
clear day
mostly sunny
partly cloudy day
partly cloudy night
mostly clear night
mostly clear night
mostly 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
mostly sunny
clear day
clear night
TEMPERATURE °F
40°
36°
51°
36°
51°
36°
55°
CHANCE OF RAIN
50%
WIND, MPH
10
10
12
12
14
15
14
10
9
8
9
9
11
12
10
8
6
6
6
7
8
8
7
6
HOW IT FEELS · DEW POINT
Dry: dew points 28 to 37°

The next seven days, and how sure we are

Forecast, with the range 8 in 10 ensemble members agree on Normal, about 54° / 38°
SAT Nov. 14 Partly cloudy Partly cloudy
40° 34°
0% rain — WNW 10 A
SUN Nov. 15 Mostly sunny; warmer Mostly sunny; warmer
51° 33°
0% rain — NNW 14 A
MON Nov. 16 Partly cloudy Partly cloudy
52° 34°
0% rain — NNW 11 A
TUE Nov. 17 Sunny Sunny
56° 35°
0% rain — W 6 A
WED Nov. 18 Sunny Sunny
60° 38°
0% rain — W 6 A
THU Nov. 19 Mostly sunny Mostly sunny
61° 41°
0% rain — WSW 6 A
FRI Nov. 20 Mostly sunny Mostly sunny
62° 41°
0% rain — WNW 5 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 Mount Sinai about 5,000 feet above the ground was over British Columbia three days ago, and over the Great Lakes a day ago, about 2,610 miles back along its path. Near the ground the air came from the Canadian Prairies; at 10,000 feet, from British Columbia. 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 1963. Next is 72° in 2022.

72°
77°
20221993
Source: NOAA RCC-ACIS, the Islip Area threaded record since 1963.
MILE2
THE GROUND

What Mount Sinai stands on

Mount Sinai’s center stands about 80 ft above sea level. Within three miles the land runs from 0 ft to 240 ft, a difference of 240 ft: rolling country. Open water lies within three miles.

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.

Mount Sinai, cut in half from south to north

A section south to north, 24 miles through the town center
0 ft100 ft200 ft300 ft MOUNT SINAI80 ftHoltsville110 ftFarmingville230 ftSelden110 ft ← S · North PatchogueN →

Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 61×. 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 13 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 Mount Sinai’s rain goes

Rain that falls on Mount Sinai runs straight into Long Island Sound and the Atlantic Ocean.

FROM THE CENTER OF MOUNT SINAI < 2 mi to Long Island Sound and the Atlantic Ocean straight to the shore

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

MILE5
THE ALMANAC

Mount Sinai’s year

1991–2020 normals · records since 1963 · Islip-Li Macarthur Airport, 11 mi south-southwest

Mount Sinai has a hot-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 25° in January. A normal year brings about 32 inches of snow; with the rain, that comes to about 46 inches of water.

39°25°41°26°48°32°58°41°68°51°77°61°83°67°81°66°75°59°64°47°54°38°44°30° JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 12 TODAY MOUNT SINAI 46.0 in rain and snowmelt
Normal high to low, by month Record high to low, by day Rain by month Freezing
July, average83° / 67°high / low, the warmest month
January, average39° / 25°high / low, the coldest month
Rain and melted snow46.0 inwettest months: December and March
Snow a year31.8 insnowiest: January
Hottest on record104°FJuly 3, 1966
Coldest on record−14°FFebruary 13, 1967
Wettest day on record13.5 inAugust 13, 2014
Snowiest day on record23.5 inJanuary 29, 2022
90° days a year8very few reach 100°
Nights at or below 32°98and 16 days that stay below freezing
Climate typeHot-summer humid continentalKöppen Dfa

AROUND THE RING

1Freeze seasonfrom the first fall freeze, about Oct. 31, to the last in spring, about April 11 (median dates)
2Lows below freezingDec. 5 to March 18; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 Mount Sinai normally reaches 54° and falls to 38°. The record high is 69°, in 1980; the record low 19°, in 1986. The most rain on this date, 2.61 in, fell in 1972.

MONTH BY MONTH
JanFebMarAprMayJunJulAugSepOctNovDec
Normal high39°41°48°58°68°77°83°81°75°64°54°44°
Normal low25°26°32°41°51°61°67°66°59°47°38°30°
Rain and melt, in3.663.294.514.063.284.003.264.243.603.973.414.71
Snow, inches10.39.46.50.60.00.00.00.00.00.00.54.5
Record high69° (2002)71° (2023)82° (2025)94° (2002)98° (1996)101° (2025)104° (1966)100° (2001)94° (1973)89° (2019)80° (2024)77° (1998)
Record low−8° (1965)−14° (1967)0° (1967)16° (1969)32° (2008)42° (2009)49° (1965)45° (1986)38° (1997)23° (1966)11° (1989)−1° (1963)

Normals 1991–2020 and records since 1963 from the Islip Area threaded record (Islip-Li Macarthur Airport, 11 miles south-southwest). NOAA, through RCC-ACIS.

MILE7
ON THE NETWORK

Around Mount Sinai on the Forecast Network

Neighboring plates

Bridgeport CT · 19 MI 19 miles northwest Stamford CT · 29 MI 29 miles west New York NY · 52 MI 52 miles west Newark NJ · 62 MI 62 miles west Philadelphia PA · 128 MI 128 miles southwest Boston MA · 141 MI 141 miles northeast
FORECASTCITY
Map of Mount Sinai, New York. Explore the plate
NEW YORK · SUFFOLK

Mount Sinai

11,623 people, 80 ft above sea level in Suffolk County.

80 ftElevation
11,623People
6 sq miLand
Clear 43°
ClearDew point 31°
1

Today in Mount Sinai

NEXT 15 HOURS
Now partly cloudy night 40° 2%
11p partly cloudy night 39° 3%
2a partly cloudy night 37° 3%
5a mostly clear night 36° 1%
8a clear day 42° 0%
11a mostly sunny 48° 1%
Clear
NEXT RAINNone this week
→
Sat0%
Partly cloudy Partly cloudy
34
40
A
Sun0%
Mostly sunny; warmer Mostly sunny; warmer
33
51
A
Mon0%
Partly cloudy Partly cloudy
34
52
A
Tue0%
Sunny Sunny
35
56
A
Wed0%
Sunny Sunny
38
60
A
Thu0%
Mostly sunny Mostly sunny
41
61
A
Fri0%
Mostly sunny Mostly sunny
41
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 1963.

2

What Mount Sinai stands on

Mount Sinai’s center stands about 80 ft above sea level. Within three miles the land runs from 0 ft to 240 ft, a difference of 240 ft: rolling country. Open water lies within three miles.

Mount Sinai, south to north Mount Sinai80 ft ← SN → 24 miles through the town center; vertical exaggeration about 117×. Colors: rock at the surface.
Elevation, center80 ft
Within 3 miles0 to 240 ft
Lie of the landRolling (240 ft of relief)
Rock at the surfaceMonmouth Group, Matawan Group and Magothy Formation
Its ageLate Cretaceous, 66 to 100 million years old
5

Mount Sinai’s year

Mount Sinai has a hot-summer humid continental climate. Summer afternoons average 83° in July; winter nights fall to about 25° in January. A normal year brings about 32 inches of snow; with the rain, that comes to about 46 inches of water.

JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC 12 46.0 in
July, average83° / 67° · high / low, the warmest month
January, average39° / 25° · high / low, the coldest month
Rain and melted snow46.0 in · wettest months: December and March
Snow a year31.8 in · snowiest: January
Hottest on record104°F · July 3, 1966
Coldest on record−14°F · February 13, 1967
Wettest day on record13.5 in · August 13, 2014
Snowiest day on record23.5 in · January 29, 2022
90° days a year8 · very few reach 100°
Nights at or below 32°98 · and 16 days that stay below freezing
Climate typeHot-summer humid continental · Köppen Dfa
1Freeze season · from the first fall freeze, about Oct. 31, to the last in spring, about April 11 (median dates)
2Lows below freezing · Dec. 5 to March 18; normal lows fall below 32°
NOVEMBER 14 IN THE RECORD

On November 14 Mount Sinai normally reaches 54° and falls to 38°. The record high is 69°, in 1980; the record low 19°, in 1986. The most rain on this date, 2.61 in, fell in 1972.

Normals 1991–2020 and records since 1963 from the Islip Area threaded record (Islip-Li Macarthur Airport, 11 miles south-southwest). NOAA, through RCC-ACIS.
3

Where the rain goes

< 2 mito the Atlanticstraight to the shore

Rain that falls on Mount Sinai runs straight into Long Island Sound and the Atlantic Ocean.