Fort Hamilton weather in September

In September, Fort Hamilton sees average daytime highs of 73°F and overnight lows near 64°F, with 3.9 in of rain across 9.5 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 77°F in the first days to 69°F by the end. The sky is clear or mostly clear about 38% of the time in September, and the air most often feels dry.

Daylight stretches from about 12 h 54 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Fort Hamilton's 2nd-clearest and 9th-windiest month. For the whole year in context, see Fort Hamilton's year-round climate.

Daytime high
73°
4th warmest
Overnight low
64°
9th coldest
Rainfall
3.9 in
9.5 wet days
Daylight
12 h 18 min
5:43 AM – 5:58 PM
Cloud cover
54%
2nd clearest
Wind
9 mph
9th windiest
Solar energy
4.22 kWh/m²
Travel score
6.9
out of 10

Fort Hamilton is neighborhood of Brooklyn in New York City.

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 77°F in the first days to 69°F by the end.

A typical September day in Fort Hamilton reaches about 73°F in the afternoon and slips back to 64°F overnight — a 10°F spread between the day's warmth and the night's chill. On most days the high lands between 67°F and 80°F. Set against its neighbours, September runs about 6°F cooler than August and about 10°F warmer than October.

50°60°70°80°151015202530
Avg high (°F)Avg low (°F)
17768
27768
37767
47767
57667
67667
77667
87666
97566
107566
117565
127465
137465
147464
157464
167364
177363
187363
197263
207262
217262
227162
237161
247161
257161
267060
277060
286960
296959
306959

How September really feels in Fort Hamilton

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Fort Hamilton weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan39° / 29°3.69.83.99.40.0
Feb40° / 29°3.48.93.510.40.1
Mar47° / 36°4.510.52.611.71.4
Apr56° / 46°3.810.90.3133.7
May65° / 55°3.511014.25.7
Jun75° / 65°3.911014.86.6
Jul80° / 71°3.811014.66.4
Aug79° / 70°3.910.2013.66.7
Sep73° / 64°3.99.5012.36.9
Oct63° / 53°4.28.8010.95.8
Nov53° / 43°3.48.60.39.73.1
Dec44° / 35°4.4101.99.10.8

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 38% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 46%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15743
25743
35743
45743
55743
65743
75644
85644
95644
105644
115545
125545
135545
145446
155545
165446
175347
185248
195248
205149
215149
225050
235149
245149
255149
265149
275248
285248
295347
305347

Chance of precipitation in September

Any precipitation

Fort Hamilton gets around 3.9 in of rain over 9.5 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 30% and peaks near 32% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
128
228
329
429
529
630
730
830
930
1030
1130
1230
1330
1430
1530
1630
1731
1831
1931
2031
2131
2232
2332
2432
2532
2632
2732
2832
2931
3031

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 27% of days. Sticky, muggy-or-worse air turns up on roughly 28% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1918282817
2918282816
31019282716
41219282615
51319282515
61419282514
71519282413
81719282412
91819282311
101919282310
112119282210
12221928229
13241928228
14251927217
15262027216
16282027215
17292026204
18302026204
19312126203
20322125193
21332224192
22352223182
23362222182
24372322171
25392321161
26402320151
27422319151
28432319141
29452318131
30462317131

Wind in September

Winds average 9 mph in September.

Across September, daily wind ranges from about 8 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
148light breeze
158light breeze
168light breeze
178light breeze
188light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 54 min at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 78 minutes over September. Sunrise moves from 5:27 AM to 5:57 AM, and sunset from 6:24 PM to 5:34 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.95:276:24
212.95:286:23
312.95:296:21
412.85:306:19
512.85:316:17
612.75:326:16
712.75:336:14
812.65:346:12
912.65:356:11
1012.55:366:09
1112.55:376:07
1212.45:386:05
1312.45:396:04
1412.45:406:02
1512.35:416:00
1612.35:435:58
1712.25:445:57
1812.25:455:55
1912.15:465:53
2012.15:475:51
2112.05:485:50
2212.05:495:48
2311.95:505:46
2411.95:515:44
2511.95:525:43
2611.85:535:41
2711.85:545:39
2811.75:555:37
2911.75:565:36
3011.65:575:34

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.22 kWh/m².

For context, solar energy here swings from a low near 1.77 kWh/m² to a high of 6.05 kWh/m² in June across the year — September's 4.22 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.8Bright
24.8Bright
34.8Bright
44.7Bright
54.7Bright
64.6Bright
74.6Bright
84.5Bright
94.5Bright
104.5Bright
114.4Bright
124.4Bright
134.3Bright
144.3Bright
154.3Bright
164.2Bright
174.2Bright
184.1Bright
194.1Bright
204.1Bright
214.0Bright
224.0Moderate
233.9Moderate
243.9Moderate
253.8Moderate
263.8Moderate
273.8Moderate
283.7Moderate
293.7Moderate
303.6Moderate
Planning a trip in September

Hazard calendar for Fort Hamilton

In seasonPeak

In September, Fort Hamilton sits inside its atlantic hurricane season. The full year is below, with each hazard's peak months called out.

Fort Hamilton sits in the Atlantic hurricane belt; the season peaks August–October.

Atlantic hurricane
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Fort Hamilton?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

6.9
Sightseeing
1st-best month of the year
5.3
Beach & pool
4th-best month of the year

September is a reasonable time to visit Fort Hamilton for sightseeing.

What to pack for Fort Hamilton in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Fort Hamilton sees daytime highs around 73°F and nights near 64°F. Worth packing: light clothes and rain gear. About 10 days see rain.

light clothesrain gear

Sea temperature near Fort Hamilton in September

The nearest coast averages about 71°F in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 8 mi away) is warmest in August at about 74°F and coldest in February near 40°F.

It's comfortable for a long swim from Jun 30 to Sep 26 — about 2.9 months when the water holds above 68°F.

40°50°60°70°80°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmcomfortable to swim
Sea temperature (°F)Comfort
Jan43Bracing
Feb40Bracing
Mar41Bracing
Apr46Bracing
May55Bracing
Jun65Cool
Jul72Refreshing
Aug74Refreshing
Sep71Refreshing
Oct63Cool
Nov55Bracing
Dec48Bracing

UV index in Fort Hamilton in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Fort Hamilton peaks around July 11 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 11UV 8Dec 22UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May7Very high
Jun8Very high
Jul8Very high
Aug6High
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Fort Hamilton in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Fort Hamilton is worst in July — around 18 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (November, 10 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodJul 1318 µg/m³Nov 1410 µg/m³
PM2.5 (µg/m³)Level
Jan12Moderate
Feb15Moderate
Mar16Moderate
Apr16Moderate
May17Moderate
Jun17Moderate
Jul18Moderate
Aug16Moderate
Sep14Moderate
Oct11Good
Nov10Good
Dec12Good
Location & terrain

Where is Fort Hamilton?

Fort Hamilton sits at 40.6°N, 74.0°W, 66 ft above sea level, in United States. The nearest listed city is Dyker Heights, 1.2 mi away.

Topography around Fort Hamilton

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Fort Hamilton.

Within 2 miles, the terrain around Fort Hamilton has only modest variations in elevation — a maximum elevation change of 161 ft around an average of 33 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 551 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,755 ft.

The land around Fort Hamilton is covered by water (46%) and artificial surfaces (45%) within 2 miles, artificial surfaces (42%) and water (42%) within 10 miles, and trees (50%) and water (29%) within 50 miles.

2 miles
161 ft
10 miles
551 ft
50 miles
1,755 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: Dyker Heights 1.2 mi · Bath Beach 1.9 mi · Sunset Park 1.9 mi · Borough Park 2.5 mi · Bensonhurst 2.5 mi · Emerson Hill 3.1 mi · Coney Island 3.7 mi · Kensington 3.7 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Fort Hamilton (40.6187°, -74.0332°, elevation 66 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).