Observed 7:45 PM EDT at KISP

Holtsville, NY weather

Clear and 46°8°.

Mostly agree

Now 46°8°

Clear

Wind: Calm; Light through 8 AM
Dew point: 37°3°; Comfortable
UV tomorrow: 4Moderate; Moderate 11 AM–4 PM · peak 4
Air today: 50Good; EPA forecast · PM2.5 (fine particles)
Pressure: 30.52 inHg1034 hPa; Steady over the last 3 h

No precipitation expected in the next 2 hours.

From forecast models

Next 48 hours

Good hours for

Low 38°3° tonight at 5 AM
Above 50°10° tomorrow by 10 AM
High 63°17° tomorrow at 3 PM
Below 50°10° tomorrow night after 9 PM

TonightDown to 38°3° by 5 AM · Clear
Tomorrow morningUp to 56°13° by 11 AM · Clear
Tomorrow afternoonUp to 63°17° by 3 PM · Clear
Tomorrow nightDown to 42°6° by 5 AM · Clear
Monday morningUp to 57°14° by 11 AM · Clear
Monday afternoonUp to 65°18° by 3 PM · Clear

Hourly forecast, next 48 hours, in the place's local time
Hour	Conditions	Temperature	Feels like	Precipitation	Wind	Humidity	Cloud cover	UV index
Sat 8p	Clear	47°8° (likely 47°8° to 52°11°)	47°8°	0%	1 mph2 km/h from W, gusts 6 mph10 km/h	68%	4%	0
Sat 9p	Clear	45°7° (likely 45°7° to 51°11°)	45°7°	0%	1 mph2 km/h from W, gusts 7 mph12 km/h	73%	4%	0
Sat 10p	Clear	44°7° (likely 44°7° to 50°10°)	44°7°	0%	1 mph2 km/h from W, gusts 7 mph12 km/h	76%	1%	0
Sat 11p	Clear	42°6° (likely 42°6° to 49°9°)	42°6°	0%	1 mph2 km/h from W, gusts 7 mph11 km/h	86%	0%	0
Sun 12a	Clear	41°5° (likely 41°5° to 48°9°)	41°5°	0%	1 mph2 km/h from NW, gusts 7 mph12 km/h	86%	0%	0
Sun 1a	Clear	41°5° (likely 41°5° to 47°8°)	41°5°	0%	2 mph3 km/h from NW, gusts 8 mph14 km/h	86%	0%	0
Sun 2a	Clear	40°4° (likely 40°4° to 47°8°)	40°4°	0%	2 mph3 km/h from NW, gusts 9 mph14 km/h	89%	0%	0
Sun 3a	Clear	39°4° (likely 39°4° to 46°8°)	39°4°	0%	2 mph3 km/h from NW, gusts 9 mph14 km/h	92%	0%	0
Sun 4a	Clear	39°4° (likely 39°4° to 46°8°)	39°4°	0%	2 mph3 km/h from NW, gusts 8 mph14 km/h	92%	0%	0
Sun 5a	Clear	38°3° (likely 38°3° to 45°7°)	38°3°	0%	2 mph3 km/h from NW, gusts 8 mph13 km/h	96%	0%	0
Sun 6a	Clear	39°4° (likely 39°4° to 46°8°)	39°4°	0%	2 mph3 km/h from N, gusts 8 mph12 km/h	92%	1%	0
Sun 7a	Sunny	39°4° (likely 39°4° to 46°8°)	37°3°	0%	3 mph5 km/h from N, gusts 7 mph11 km/h	92%	1%	0
Sun 8a	Sunny	41°5° (likely 41°5° to 46°8°)	39°4°	0%	3 mph5 km/h from N, gusts 6 mph10 km/h	89%	2%	0
Sun 9a	Sunny	47°8° (likely 47°8° to 49°9°)	46°8°	0%	3 mph5 km/h from N, gusts 6 mph9 km/h	71%	0%	1
Sun 10a	Sunny	52°11° (likely 52°11° to 56°13°)	52°11°	0%	3 mph5 km/h from N, gusts 7 mph11 km/h	61%	0%	2
Sun 11a	Sunny	56°13° (likely 56°13° to 60°16°)	56°13°	0%	3 mph5 km/h from N, gusts 6 mph9 km/h	53%	0%	3
Sun 12p	Sunny	58°14° (likely 58°14° to 63°17°)	58°14°	0%	3 mph5 km/h from N, gusts 7 mph11 km/h	47%	0%	4
Sun 1p	Sunny	61°16° (likely 60°16° to 64°18°)	61°16°	0%	3 mph5 km/h from NW, gusts 7 mph11 km/h	42%	0%	4
Sun 2p	Sunny	62°17° (likely 61°16° to 66°19°)	62°17°	0%	3 mph5 km/h from NW, gusts 6 mph10 km/h	41%	0%	4
Sun 3p	Sunny	63°17° (likely 61°16° to 66°19°)	63°17°	0%	3 mph5 km/h from W, gusts 6 mph10 km/h	39%	0%	3
Sun 4p	Sunny	63°17° (likely 60°16° to 65°18°)	63°17°	0%	3 mph5 km/h from SW, gusts 8 mph12 km/h	41%	0%	2
Sun 5p	Sunny	61°16° (likely 59°15° to 63°17°)	61°16°	0%	3 mph5 km/h from SW, gusts 7 mph11 km/h	46%	0%	1
Sun 6p	Clear	58°14° (likely 54°12° to 58°14°)	58°14°	0%	3 mph5 km/h from SW, gusts 7 mph12 km/h	53%	0%	0
Sun 7p	Clear	55°13° (likely 51°11° to 55°13°)	55°13°	0%	2 mph3 km/h from SW, gusts 7 mph11 km/h	61%	0%	0
Sun 8p	Clear	50°10° (likely 49°9° to 53°12°)	50°10°	0%	2 mph3 km/h from SW, gusts 8 mph12 km/h	77%	0%	0
Sun 9p	Clear	48°9° (likely 48°9° to 53°12°)	48°9°	0%	2 mph3 km/h from SW, gusts 8 mph12 km/h	83%	0%	0
Sun 10p	Clear	48°9° (likely 47°8° to 53°12°)	48°9°	0%	2 mph3 km/h from SW, gusts 10 mph16 km/h	86%	0%	0
Sun 11p	Clear	46°8° (likely 46°8° to 53°12°)	46°8°	0%	2 mph3 km/h from SW, gusts 8 mph13 km/h	93%	1%	0
Mon 12a	Clear	46°8° (likely 46°8° to 52°11°)	46°8°	0%	2 mph3 km/h from W, gusts 11 mph18 km/h	89%	1%	0
Mon 1a	Clear	45°7° (likely 45°7° to 52°11°)	44°7°	0%	3 mph5 km/h from W, gusts 12 mph19 km/h	93%	1%	0
Mon 2a	Clear	45°7° (likely 45°7° to 51°11°)	44°7°	0%	3 mph5 km/h from W, gusts 11 mph17 km/h	93%	1%	0
Mon 3a	Clear	43°6° (likely 43°6° to 50°10°)	41°5°	0%	3 mph5 km/h from W, gusts 11 mph17 km/h	96%	1%	0
Mon 4a	Clear	43°6° (likely 43°6° to 49°9°)	40°4°	0%	5 mph8 km/h from W, gusts 11 mph18 km/h	96%	0%	0
Mon 5a	Clear	42°6° (likely 42°6° to 48°9°)	39°4°	0%	5 mph8 km/h from W, gusts 12 mph19 km/h	96%	0%	0
Mon 6a	Clear	41°5° (likely 41°5° to 48°9°)	38°3°	0%	5 mph8 km/h from W, gusts 11 mph18 km/h	100%	0%	0
Mon 7a	Sunny	42°6° (likely 42°6° to 47°8°)	39°4°	0%	5 mph8 km/h from W, gusts 11 mph17 km/h	96%	2%	0
Mon 8a	Sunny	43°6° (likely 43°6° to 48°9°)	40°4°	0%	5 mph8 km/h from W, gusts 10 mph16 km/h	93%	1%	0
Mon 9a	Sunny	48°9° (likely 48°9° to 51°11°)	46°8°	0%	5 mph8 km/h from W, gusts 11 mph18 km/h	80%	1%	1
Mon 10a	Sunny	53°12° (likely 53°12° to 55°13°)	53°12°	0%	6 mph10 km/h from W, gusts 13 mph21 km/h	71%	9%	2
Mon 11a	Sunny	57°14° (likely 57°14° to 59°15°)	57°14°	0%	6 mph10 km/h from W, gusts 12 mph20 km/h	67%	7%	3
Mon 12p	Sunny	60°16° (likely 59°15° to 63°17°)	60°16°	0%	6 mph10 km/h from W, gusts 12 mph19 km/h	60%	6%	4
Mon 1p	Sunny	63°17° (likely 61°16° to 66°19°)	63°17°	0%	7 mph11 km/h from W, gusts 11 mph18 km/h	54%	11%	4
Mon 2p	Sunny	64°18° (likely 62°17° to 67°19°)	64°18°	0%	7 mph11 km/h from W, gusts 11 mph17 km/h	52%	0%	4
Mon 3p	Sunny	65°18° (likely 61°16° to 68°20°)	65°18°	0%	7 mph11 km/h from W, gusts 12 mph19 km/h	50%	0%	3
Mon 4p	Sunny	65°18° (likely 62°17° to 68°20°)	65°18°	0%	7 mph11 km/h from W, gusts 12 mph19 km/h	52%	3%	2
Mon 5p	Sunny	64°18° (likely 62°17° to 67°19°)	64°18°	0%	7 mph11 km/h from W, gusts 10 mph16 km/h	56%	2%	1
Mon 6p	Clear	62°17° (likely 57°14° to 64°18°)	62°17°	0%	6 mph10 km/h from W, gusts 9 mph14 km/h	60%	0%	0
Mon 7p	Clear	59°15° (likely 54°12° to 62°17°)	59°15°	0%	5 mph8 km/h from W, gusts 8 mph13 km/h	69%	0%	0

Days ahead

Shaded: typical range for these dates (1991–2020)

Today, Oct 24. Cloudy. High 60°16°, low 37°3°. Typical 61°16° / 44°7°. Dry. Mostly agree.
1. Evening
  6 PM–midnight
  Clear, 47°8°
  Dry
2. Overnight
  midnight–6 AM
  Clear, 38°3°
  Dry
Official NWS forecast
Tonight: Patchy frost after 5am. Mostly clear, with a low around 37. Northwest wind around 2 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
58°14°–62°17°
Low, likely
37°3°–42°6°
Typical high / low
61°16° / 44°7°
Wind
8 mph14 km/h, gusts 14 mph23 km/h
UV peak
4
Tomorrow, Oct 25. Sunny. High 63°17°, low 41°5°. Typical 61°16° / 44°7°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 41°5°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 63°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 50°10°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 42°6°
  Dry
Official NWS forecast
Day: Sunny. High near 63, with temperatures falling to around 61 in the afternoon. Northwest wind around 3 mph.
Night: Clear, with a low around 41. Southwest wind around 5 mph.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
61°16°–66°19°
Low, likely
41°5°–44°7°
Typical high / low
61°16° / 44°7°
Wind
7 mph12 km/h, gusts 14 mph23 km/h
UV peak
4
Monday, Oct 26. Sunny. High 66°19°, low 48°9°. Typical 61°16° / 44°7°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 43°6°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 65°18°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 53°12°
  Dry
Official NWS forecast
Day: Sunny. High near 66, with temperatures falling to around 64 in the afternoon. West wind around 7 mph.
Night: Clear. Low around 48, with temperatures rising to around 50 overnight. Northwest wind 3 to 8 mph.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
63°17°–67°19°
Low, likely
43°6°–48°9°
Typical high / low
61°16° / 44°7°
Wind
9 mph14 km/h, gusts 21 mph34 km/h
UV peak
4
Tuesday, Oct 27. Mostly sunny. High 57°14°, low 41°5°. Typical 60°16° / 43°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 51°10°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 55°13°
  Dry
3. Evening
  6 PM–midnight
  Clear, 48°9°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 44°7°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 57.
Night: Mostly clear, with a low around 41.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
56°13°–59°15°
Low, likely
40°4°–50°10°
Typical high / low
60°16° / 43°6°
Wind
12 mph19 km/h, gusts 24 mph39 km/h
UV peak
4
Wednesday, Oct 28. Partly sunny. High 58°14°, low 46°8°. Typical 60°16° / 43°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 45°7°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 58°14°
  Dry
3. Evening
  6 PM–midnight
  Mostly clear, 52°11°
  Dry
4. Overnight
  midnight–6 AM
  Mostly clear, 52°11°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 58.
Night: Partly cloudy, with a low around 46.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
56°13°–60°16°
Low, likely
39°4°–46°8°
Typical high / low
60°16° / 43°6°
Wind
9 mph15 km/h, gusts 15 mph24 km/h
UV peak
4
Thursday, Oct 29. Partly sunny. High 64°18°, low 52°11°. Typical 60°16° / 43°6°. Dry. Mostly agree.
1. Morning
  6 AM–noon
  Sunny, 52°11°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 62°17°
  Dry
3. Evening
  6 PM–midnight
  Clear, 58°14°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 55°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 64.
Night: Mostly clear, with a low around 52.
Mostly agreeIndependent forecasts are fairly close; small surprises are possible.
High, likely
62°17°–65°18°
Low, likely
47°8°–54°12°
Typical high / low
60°16° / 43°6°
Wind
15 mph24 km/h, gusts 22 mph36 km/h
UV peak
4
Friday, Oct 30. Mostly sunny. High 68°20°, low 51°11°. Typical 59°15° / 42°6°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 54°12°
  Dry
2. Afternoon
  noon–6 PM
  Sunny, 69°20°
  Dry
3. Evening
  6 PM–midnight
  Clear, 60°15°
  Dry
4. Overnight
  midnight–6 AM
  Clear, 53°12°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Sunny, with a high near 68.
Night: Mostly clear, with a low around 51.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
65°18°–72°22°
Low, likely
51°11°–56°13°
Typical high / low
59°15° / 42°6°
Wind
13 mph20 km/h, gusts 21 mph34 km/h
UV peak
4
Saturday, Oct 31. Partly sunny. High 64°18°, low 51°11°. Typical 59°15° / 42°6°. Dry. Forecasts differ.
1. Morning
  6 AM–noon
  Sunny, 52°11°
  Dry
2. Afternoon
  noon–6 PM
  Mostly sunny, 65°18°
  Dry
3. Evening
  6 PM–midnight
  Cloudy, 56°13°
  Dry
4. Overnight
  midnight–6 AM
  Cloudy, 56°13°
  Dry
Hours this far out come from computer models only.
Official NWS forecast
Day: Mostly sunny, with a high near 64.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
57°14°–68°20°
Low, likely
50°10°–53°12°
Typical high / low
59°15° / 42°6°
Wind
9 mph15 km/h, gusts 19 mph31 km/h
UV peak
4
Sunday, Nov 1. Cloudy. High 65°18°, low 55°13°. Typical 58°14° / 42°6°. Rain 0.01 in0.3 mm, 30% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Partly sunny, 58°14°
  Dry
2. Afternoon
  noon–6 PM
  Cloudy, 65°18°
  Dry
3. Evening
  6 PM–midnight
  Drizzle, 62°16°
  30% chance · 0.01 in0.3 mm
4. Overnight
  midnight–6 AM
  Drizzle, 62°17°
  40% chance · 0.12 in2.9 mm
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
60°16°–70°21°
Low, likely
54°12°–57°14°
Typical high / low
58°14° / 42°6°
Wind
11 mph18 km/h, gusts 27 mph43 km/h
UV peak
3
Monday, Nov 2. Drizzle. High 65°18°, low 60°16°. Typical 58°14° / 42°6°. Rain 0.3 in7.6 mm, 40% chance. Forecasts differ.
1. Morning
  6 AM–noon
  Showers, 62°17°
  40% chance · 0.17 in4.2 mm
2. Afternoon
  noon–6 PM
  Showers, 64°18°
  30% chance · 0.06 in1.5 mm
3. Evening
  6 PM–midnight
  Drizzle, 63°17°
  30% chance · 0.02 in0.5 mm
Hours this far out come from computer models only.
The National Weather Service writes about seven days ahead; this day is our model forecast only.
Forecasts differIndependent forecasts disagree; expect changes and plan for the range.
High, likely
62°17°–70°21°
Low, likely
57°14°–64°18°
Typical high / low
58°14° / 42°6°
Wind
23 mph36 km/h, gusts 39 mph63 km/h
UV peak
1

10 days15 days30 days

The outlook

Today
Dry, high 60°, low 37°.
Tomorrow
Dry, high 63°, low 41°, warming up.
Monday
Dry, high 66°, low 48°, warming up.
Rest of week
Mostly dry, highs 57–68°.

Want the meteorologists’ reasoning? Read the NWS forecast discussion (OKX) (opens in a new tab)

What changed since yesterday

No meaningful changes from yesterday’s forecast.

Radar

Radar data: NOAA MRMS, rendered by forecast.blue

Radar loads when scrolled into view

Full-screen radar

Rivers

NOAA river gauges within 25 mi

Great South Bay at Watch Hill (IN MLLW)

8.8 mi

Below flood stage

Level: 1.7 ft

Reading from Sat 7 PM · NWS gauge page

Flax Pond at Old Field (IN MLLW)

12 mi

Below flood stage

Level: 3.8 ft

Reading from Sat 6:24 PM · NWS gauge page

Moriches Bay at Moriches Bay (IN MLLW)

16 mi

Below flood stage

Level: 2.9 ft

Reading from Sat 6:48 PM · NWS gauge page

Carlls River at Babylon

17 mi

Level: 0.5 ft
Flow: 15 cfs

Reading from Sat 7 PM · NWS gauge page

For your home

What this week’s weather means for heating, cooling, pipes and fresh air.

Heating this week

About 69% less heating than a typical week.

This week 29Typical 93

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F: 23
h below 17°F: 0
h below 5°F: 0

47, 17 and 5°F are the test points heat pumps are rated at. About 13 hours are near freezing and damp, when outdoor units defrost more often.

Comfort

Dry air outside (dew point 37°F).

Open the windows?

Sun, 1:00 PM–5:00 PM

Good stretch to open the windows.

Is this typical?

Islip-Li Macarthur Airport · official normals 1991–2020 · records 1963–2026

Oct 24, today vs a typical year

Today’s expected high is about typical for the date.

Last 7 days vs normal

On average 1° colder than normal (daily mean temperature).

−6°−3°SunOct 18
−4°−2°MonOct 19
+3°+1°TueOct 20
+2°+1°WedOct 21
+4°+2°ThuOct 22
−4°−2°FriOct 23
—SatOct 24

Holtsville weather by month: normals, records, snow and freeze dates

Sun & moon

Sun

Daylight: 10 h 45 min; Losing 2 min 30 s a day; shortest Dec 21, 1 h 30 min less
Golden hour: 5:20–6:15 PM; Morning 6:56–7:51 AM
Blue hour: 6:15–6:26 PM; Morning 6:45–6:56 AM; first light 6:45 AM

Stars tonight? Fair

Clear 8:14 PM–6:46 AM, but the moon is 99% lit and up.

Moon

Waxing gibbous

98% lit · growing

Today: sets 5:24 AM · rises 4:55 PM
Full moon: Oct 26
New moon: Nov 9

Looking south from Holtsville. The highest point on the skyline is about 700 ft, 13 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.

Holtsville, NY weather

Next 2 hours

Next 48 hours

Days ahead

The outlook

Today

Tomorrow

Monday

Rest of week

What changed since yesterday

Radar

Rivers

Great South Bay at Watch Hill (IN MLLW)

Flax Pond at Old Field (IN MLLW)

Moriches Bay at Moriches Bay (IN MLLW)

Carlls River at Babylon

For your home

Heating this week

Heat-pump hours, next 7 days

Comfort

Open the windows?

Is this typical?

Oct 24, today vs a typical year

Last 7 days vs normal

Sun & moon

Sun

Stars tonight? Fair

Moon