Weather in Stony Brook

14-day forecast · updated today, Wednesday, October 28, at 11:58 pm (EDT)

Now · clear 51 °F

Feels like: 47 °F
Low / high: 44 / 58 °F
Rain: 0%
Wind: 7 mph S

↘ 30.33 inHg · falling

Today in Stony Brook: overcast, 44 °F to 58 °F, with a 0% chance of rain and a light breeze from the south (7 mph). Tomorrow, clear sky, 50 °F to 67 °F and a 1% chance of rain. The warmest day of the week is Friday 30, at 67 °F. Next likely rain: Wednesday 4 (25%).

Temperatures for the next 14 days

58° 44°
Today
67° 50°
Thu 29
67° 51°
Fri 30
58° 47°
Sat 31
61° 47°
Sun 1
64° 51°
Mon 2
63° 53°
Tue 3
64° 54°
Wed 4
65° 56°
Thu 5
63° 54°
Fri 6
59° 51°
Sat 7
58° 44°
Sun 8
55° 40°
Mon 9
55° 42°
Tue 10

Day by day

Day	Sky	Low / high	Rain	Max wind	Max wave	High tides	Model
Today · 28	Overcast	44 / 58 °F	0%	10 mph E	0.8 ft	1:07 am · 1:23 pm	HRRR
Thu 29	Clear sky	50 / 67 °F	1%	11 mph SW	0.9 ft	1:59 am · 2:15 pm	HRRR + NBM
Fri 30	Light drizzle	51 / 67 °F	6%	13 mph WNW	1.5 ft	2:53 am · 3:12 pm	NBM
Sat 31	Partly cloudy	47 / 58 °F	0%	12 mph NNW	1.0 ft	3:52 am · 4:13 pm	NBM
Sun 1	Overcast	47 / 61 °F	0%	6 mph WSW	0.5 ft	3:54 am · 4:18 pm	NBM
Mon 2	Overcast	51 / 64 °F	5%	6 mph WSW	0.6 ft	4:59 am · 5:26 pm	NBM
Tue 3	Overcast	53 / 63 °F	11%	12 mph E	1.0 ft	6:05 am · 6:32 pm	NBM
Wed 4	Partly cloudy	54 / 64 °F	25% · 0.19 in	12 mph ESE	0.9 ft	7:06 am · 7:33 pm	NBM
Thu 5	Clear sky	56 / 65 °F	33% · 0.34 in	11 mph ESE	0.3 ft	8:00 am · 8:28 pm	NBM
Fri 6	Light rain	54 / 63 °F	33% · 0.43 in	11 mph E	1.0 ft	8:49 am · 9:17 pm	NBM
Sat 7	Light rain	51 / 59 °F	31% · 0.12 in	11 mph NNW	3.2 ft	9:33 am · 10:02 pm	NBM
Sun 8	Overcast	44 / 58 °F	22% · 0.08 in	11 mph NNW	2.2 ft	10:14 am · 10:44 pm	NBM + ECMWF
Mon 9	Clear sky	40 / 55 °F	21%	7 mph NNW	1.2 ft	10:53 am · 11:24 pm	ECMWF
Tue 10	Overcast	42 / 55 °F	14%	8 mph NE	1.6 ft	11:31 am	ECMWF

Each hour comes from the best model for this spot: HRRR until Thursday 29 6:00 pm; then NBM until Sunday 8 8:00 pm; then ECMWF until Thursday 12 10:00 am; then GFS.

Each day comes from the best model covering this spot: regional ones first (HRRR and NBM in the U.S., AROME, ICON-EU), then ECMWF; day 16, NOAA GFS. Waves: Météo-France up to day 10, then ECMWF WAM, coarser and further offshore. High tides: our own tide calculation.

Today, every 3 hours

Time	12:00 am	3:00 am	6:00 am	9:00 am	12:00 pm	3:00 pm	6:00 pm	9:00 pm
Sky	Clear	Clear	Clear	Mainly clear	Overcast	Overcast	Overcast	Mainly clear
Temperature	44°	45°	47°	52°	55°	57°	55°	52°
Chance of rain	0%	0%	0%	0%	0%	0%	0%	0%
Rain	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in
Wind (mph)	4 SSE	8 NNE	7 NE	9 NE	7 NE	8 ENE	4 SSE	3 SSE
Humidity	84%	69%	66%	65%	69%	64%	58%	76%
UV	0	0	0	1	3	2	0	0
Model	HRRR	HRRR	HRRR	HRRR	HRRR	HRRR	HRRR	HRRR

Do the models agree?

Medium confidence

They broadly agree, but not quite on wind on Friday 30: take it with some caution.

What 6 forecast models say for the next few days. The closer they are, the more reliable the forecast.

HighRainWind

Do the models agree? · High
High (°F)	Today	Thu 29	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3
ECMWF	59°	64°	69°	56°	59°	64°	65°
AIFS	58°	64°	67°	56°	57°	64°	65°
GFS	60°	66°	68°	56°	60°	64°	62°
ICON	59°	65°	68°	55°	62°	66°	68°
HRRR	58°	67°	63°	—	—	—	—
NBM	59°	65°	67°	58°	61°	64°	63°
Confidence	high	high	high	high	high	high	high

Do the models agree? · Rain
Rain	Today	Thu 29	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3
ECMWF	0	0	0.02 in	0	0	0	0
AIFS	0	0	0	0	0	0	0
GFS	0	0	0	0	0	0	0
ICON	0	0	0	0	0	0	0
HRRR	0	0	0	—	—	—	—
NBM	0	0	0	0	0	0	0
Confidence	high	high	high	high	high	high	high

Do the models agree? · Wind
Wind (mph)	Today	Thu 29	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3
ECMWF	615	1021	1329	924	621	1124	1223
AIFS	7	13	15	13	8	11	13
GFS	910	1123	2028	1420	916	1217	1420
ICON	513	820	1228	922	719	719	1126
HRRR	1016	1121	2030	—	—	—	—
NBM	710	1116	1320	1215	69	611	1216
Confidence	high	high	medium	high	high	high	high

Chance of rain from the ensemble models

Model	Today	Thu 29	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3
ECMWF (51 scenarios)	0%	0%	8%	0%	0%	6%	16%
GFS (GEFS, 31 scenarios)	0%	0%	0%	0%	3%	19%	26%
NBM (NOAA)	0%	1%	6%	0%	0%	5%	11%
Thunderstorm (NBM)	0%	0%	1%	0%	0%	0%	1%

Each model's day runs midnight to midnight local time; models that reach fewer days are left blank. Rain: daily total. Wind: the day's highest average wind and, in small type, the strongest gust. Highlighted: values that stand out from the rest. The chance of rain comes from many runs of the same model with slightly different starting data.

Outlook

How the coming weeks and months compare with what is normal for the time of year. It is a trend, not a day-by-day forecast.

Next few weeks, compared with normal: warmer and normal rain.

Next 6 weeks

When	TemperatureTemp.	Rain	Typical high / low
Nov 2 – Nov 8Nov 2–Nov 8	Well above +6.1 °F	A bit above +39%	—
Nov 9 – Nov 15Nov 9–Nov 15	A bit above +0.9 °F	Normal	53° / 45°
Nov 16 – Nov 22Nov 16–Nov 22	A bit above +2.2 °F	Normal	53° / 45°
Nov 23 – Nov 29Nov 23–Nov 29	A bit above +2.3 °F	A bit above +30%	50° / 44°
Nov 30 – Dec 6Nov 30–Dec 6	A bit above +1.8 °F	A bit above +21%	48° / 41°

Coming months

When	TemperatureTemp.	Rain
November	A bit above +1.1 °F	A bit above +25%
December	A bit above +2.3 °F	A bit above +32%
January	Above +3.6 °F	A bit above +42%
February	Above +2.7 °F	A bit above +35%
March	Above +2.7 °F	A bit above +26%

Weeks: ECMWF 46-day (average of its scenarios), against the normal of the last 20 years for those dates. Months: ECMWF SEAS5. Rain: total against normal. The further ahead, the closer it gets to normal and the less detail it can give. The long-range sea temperature isn't usable at this spot (the model's grid cell falls on land).

Stony Brook climate by monthClimate by month

Normal weather for each month (1991–2020 averages)

The best time to visit Stony Brook is from June to September: highs of 74 °F to 82 °F, about 9 rainy days a month and 7 hours of sunshine a day.

Hurricane season: from July to September. In the last 30 years (1996–2025), 9 tropical cyclones passed within 93 mi of Stony Brook, about 3 every 10 years. The most recent: Henri, in August 2021.

39° 25°

JanJ
41° 25°

FebF
47° 31°

MarM
58° 40°

AprA
68° 49°

MayM
77° 59°

JunJ
82° 65°

JulJ
81° 65°

AugA
74° 58°

SepS
64° 48°

OctO
54° 39°

NovN
45° 31°

DecD

Highs and lows
Monthly rainfall
Best time

Month	High	Low	Rain	Rainy daysDays	Sun (h/day)	Water	Waves	Cyclones
JanuaryJan	39°	25°	3.38 in	8	3.7	39°	1.7 ft	–
FebruaryFeb	41°	25°	2.93 in	7	5.0	35°	1.6 ft	–
MarchMar	47°	31°	4.19 in	9	5.5	37°	1.6 ft	–
AprilApr	58°	40°	3.91 in	9	6.1	44°	1.5 ft	–
MayMay	68°	49°	3.33 in	10	6.9	54°	1.2 ft	–
JuneJun	77°	59°	3.83 in	10	7.6	65°	1.0 ft	1
JulyJul	82°	65°	3.59 in	9	8.0	72°	1.0 ft	3
AugustAug	81°	65°	3.76 in	10	7.3	74°	1.0 ft	3
SeptemberSep	74°	58°	3.46 in	8	6.0	71°	1.4 ft	2
OctoberOct	64°	48°	4.11 in	8	4.7	64°	1.7 ft	–
NovemberNov	54°	39°	3.38 in	7	3.8	55°	1.7 ft	–
DecemberDec	45°	31°	3.99 in	9	3.3	46°	1.7 ft	–

Month	Water	Waves	Cyclones
Jan	39°	1.7 ft	–
Feb	35°	1.6 ft	–
Mar	37°	1.6 ft	–
Apr	44°	1.5 ft	–
May	54°	1.2 ft	–
Jun	65°	1.0 ft	1
Jul	72°	1.0 ft	3
Aug	74°	1.0 ft	3
Sep	71°	1.4 ft	2
Oct	64°	1.7 ft	–
Nov	55°	1.7 ft	–
Dec	46°	1.7 ft	–

Days: rainy days in the month. Sun: hours a day.

A normal year brings 43.85 in of rain on about 102 days and about 2,050 hours of sunshine.

Cyclones: how many tropical cyclones (tropical storms, hurricanes and typhoons) passed within 93 mi in each month from 1996 to 2025, according to IBTrACS (NOAA).

1991–2020 averages. Highs, lows and rainfall: TerraClimate; rainy days (0.04 in or more): NASA POWER (MERRA-2); sunshine hours: estimated from solar radiation; water: NOAA OISST; waves (average height): ERA5, 2011–2020. Normals are not a forecast: any given year can turn out very different. Sources and licenses

Temperature

Now51 °Ffeels like 47 °F

Tomorrow50 / 67 °F

It's 51 °F now (feels like 47 °F). Today, 44 °F to 58 °F; tomorrow, 50 °F to 67 °F.

Chance of rain

Today 0%
Thu 29 1%
Fri 30 6%
Sat 31 0%
Sun 1 0%
Mon 2 5%
Tue 3 11%

Today the chance of rain reaches 0%. The next day with likely rain is Wednesday 4: 25% and 0.19 in.

No rain in the last 7 days.

Humidity and dew point

Humidity87%

Dew point47 °F

Humidity is 87% now and the dew point is 47 °F.

The dew point is the temperature at which the air becomes saturated: the higher it is, the heavier the air feels.

Visibility and fog

Now9.3 migood

Clouds16%

Visibility is good now (9.3 mi). No fog expected today.

UV index

Now0

Today's peak3moderate

Thu 29: 3 · Fri 30: 3 · Sat 31: 3

Index	Level	What to do
0–2	low	No special protection needed.
3–5	moderate	Hat, sunglasses and sunscreen around midday.
6–7	high	Sunscreen, hat and shade between 12 and 4 pm.
8–10	very high	Avoid the midday sun; reflection off the water adds to it.
11+	extreme	Avoid the sun between 11 am and 5 pm; protect yourself even if it is cloudy.

Reflection off water and sand adds radiation: protect yourself more on a boat or at the beach.

Barometric pressure

↗ Rising Anglers say fish bite less for a while
→ Steady Anglers expect normal activity
↘ Falling · now Anglers say fish feed more before the change

30.0030.2030.40 30.02

Falling now (−0.05 inHg in 3 hours). Over the next 48 hours: −0.08 inHg. Falling pressure: anglers say fish feed more before the change. Fast changes, either way, tend to affect fishing.

Air and pollen

Air qualityGood · 44

Saharan dustNo

Previous days

The weather over the last 30 days, as the models analyzed it. Tap a day to see it hour by hour.

Day	Sky	Low / high	Max wind
Tue 27	Mainly clear	50 / 59 °F	8 mph N
Mon 26	Clear sky	45 / 68 °F	7 mph W
Sun 25	Partly cloudy	41 / 64 °F	5 mph WNW
Sat 24	Overcast	42 / 61 °F	7 mph NNW
Fri 23	Overcast	49 / 58 °F	9 mph NNE
Thu 22	Overcast	49 / 64 °F	13 mph N
Wed 21	Overcast	50 / 60 °F	14 mph NNE

Show all 30 days

Day	Sky	Low / high	Rain	Max wind
Tue 20	Overcast	49 / 66 °F	0	13 mph NNE
Mon 19	Mainly clear	42 / 61 °F	0	7 mph NNE
Sun 18	Clear sky	41 / 56 °F	0	11 mph NNE
Sat 17	Heavy drizzle	46 / 64 °F	0.20 in	14 mph NNW
Fri 16	Rain	58 / 69 °F	0.50 in	11 mph SSW
Thu 15	Partly cloudy	56 / 66 °F	0	9 mph NNE
Wed 14	Light drizzle	66 / 75 °F	0.04 in	12 mph WSW
Tue 13	Partly cloudy	57 / 68 °F	0	12 mph S
Mon 12	Drizzle	55 / 70 °F	0.07 in	12 mph N
Sun 11	Rain	57 / 61 °F	1.43 in	17 mph ENE
Sat 10	Overcast	53 / 68 °F	0	6 mph ENE
Fri 9	Overcast	52 / 71 °F	0	8 mph WNW
Thu 8	Clear sky	60 / 74 °F	0	11 mph WSW
Wed 7	Clear sky	44 / 64 °F	0	11 mph SW
Tue 6	Clear sky	49 / 61 °F	0	9 mph NW
Mon 5	Overcast	55 / 70 °F	0	13 mph WNW
Sun 4	Heavy drizzle	56 / 62 °F	0.30 in	9 mph NE
Sat 3	Overcast	60 / 70 °F	0	10 mph NE
Fri 2	Drizzle	68 / 77 °F	0.06 in	10 mph SW
Thu 1	Overcast	64 / 73 °F	0	10 mph SW
Wed 30	Overcast	60 / 71 °F	0	6 mph W
Tue 29	Light drizzle	58 / 69 °F	0.01 in	5 mph WNW
Mon 28	Light rain	58 / 63 °F	0.72 in	13 mph NNE

These are the models at the start of each day (ECMWF and GFS; waves from Météo-France), not readings from a weather station: there can be differences at specific spots.

Questions about the weather in Stony BrookQuestions

What's the weather like today in Stony Brook?

Overcast, from 44 °F to 58 °F, with a light breeze from the south (7 mph) and a 0% chance of rain.

Will it rain tomorrow in Stony Brook?

On Thursday 29 the chance of rain is 1% (0.00 in): clear sky.

How warm will it be this week?

Between a low of 44 °F and a high of 67 °F; the warmest day, Friday 30.

What's the UV index today?

It reaches 3 (moderate). Hat, sunglasses and sunscreen around midday.

Is the pressure rising or falling?

It's 30.33 inHg and falling: −0.08 inHg over the last 24 hours.

When is the best time to visit Stony Brook?

The best time to visit Stony Brook is from June to September: highs of 74 °F to 82 °F, about 9 rainy days a month and 7 hours of sunshine a day.

What is the weather like in Stony Brook in October?

In October, Stony Brook normally sees highs of 64 °F and lows of 48 °F, with about 8 rainy days (4.11 in for the month) and 5 hours of sunshine a day. The sea is around 64 °F. These are 1991–2020 averages.

What are the warmest and wettest months in Stony Brook?

The warmest is July, with average highs of 82 °F, and the coldest January, with lows of 25 °F. The wettest is March (4.19 in) and the driest, February.

When is hurricane season in Stony Brook?

Hurricane season: from July to September. In the last 30 years (1996–2025), 9 tropical cyclones passed within 93 mi of Stony Brook, about 3 every 10 years. The most recent: Henri, in August 2021.

More about Stony Brook today

Weather near Stony Brook

Only places with a different forecast: spots a few miles apart share the same model cell and wouldn't add anything.

Learn more

Weather: Open-Meteo, CC BY 4.0, with the best model for each spot and lead time (NOAA HRRR and NBM in the U.S., Météo-France AROME, DWD ICON-EU, ECMWF IFS and NOAA GFS); ECMWF grid point 13 mi away. The comparison also uses ICON (DWD), AIFS (ECMWF) and ARPEGE (Météo-France). Outlook: ECMWF 46-day and SEAS5. Chance of rain from ensemble models (ECMWF, GEFS and NBM). UV, air quality and pollen: CAMS (Copernicus).

Forecast from Open-Meteo (CC BY 4.0) with models from ECMWF, NOAA, Météo-France, DWD, Copernicus Marine and CAMS. Updated at 11:58 pm (local time).

Spotted a mistake? Tell us · Where the weather and sea data come from