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Observed 5:40 PM EDT at KISP

Smithtown, NY weather

Sunny and 57°14°.

Today: low 39°4° (likely 38°3° to 43°6°), high 60°16° (likely 59°15° to 62°17°).

Mostly agree

Now 57°14°

Sunny

Wind
5 mph7 km/h
From the northwest. Light through 6 AM
Dew point
28°−2°
Dry · up to 38°3° by 7 PM (comfortable)
UV tomorrow
4Moderate
Moderate 11 AM–4 PM · peak 4
Air today
50Good
EPA forecast · PM2.5 (fine particles)
Pressure
30.5 inHg1033 hPa
Steady over the last 3 h

Next 2 hours

No precipitation expected in the next 2 hours.

Next 48 hours

3°2° warmer than this time yesterday (58°14° then, 61°16° now)

Good hours for
  • Below 50°10° tonight after 8 PM
  • Low 39°4° tonight at 5 AM
  • Above 50°10° tomorrow by 10 AM
  • High 63°17° tomorrow at 3 PM
  1. TonightDown to 39°4° by 5 AM · Clear
  2. Tomorrow morningUp to 56°13° by 11 AM · Clear
  3. Tomorrow afternoonUp to 63°17° by 3 PM · Clear
  4. Tomorrow nightDown to 43°6° by 5 AM · Clear
  5. Monday morningUp to 57°14° by 11 AM · Clear
  6. Monday afternoonUp to 66°19° by 3 PM · Clear
Hourly forecast, next 48 hours, in the place's local time
HourConditionsTemperatureFeels likePrecipitationWindHumidityCloud coverUV index
Sat 6pClear56°13° (likely 54°12° to 56°13°)56°13°0%2 mph3 km/h from NW, gusts 7 mph11 km/h51%36%0
Sat 7pMostly clear53°12° (likely 51°11° to 53°12°)53°12°0%2 mph3 km/h from W, gusts 6 mph9 km/h57%36%0
Sat 8pMostly clear48°9° (likely 48°9° to 52°11°)48°9°0%1 mph2 km/h from W, gusts 5 mph8 km/h68%35%0
Sat 9pMostly clear46°8° (likely 46°8° to 51°11°)46°8°0%1 mph2 km/h from W, gusts 5 mph8 km/h73%32%0
Sat 10pClear45°7° (likely 44°7° to 49°9°)45°7°0%1 mph2 km/h from W, gusts 6 mph10 km/h76%1%0
Sat 11pClear44°7° (likely 43°6° to 48°9°)44°7°0%1 mph2 km/h from W, gusts 6 mph10 km/h79%0%0
Sun 12aClear43°6° (likely 42°6° to 48°9°)43°6°0%1 mph2 km/h from NW, gusts 6 mph10 km/h82%1%0
Sun 1aClear43°6° (likely 42°6° to 47°8°)43°6°0%1 mph2 km/h from NW, gusts 7 mph11 km/h82%2%0
Sun 2aClear41°5° (likely 41°5° to 47°8°)41°5°0%1 mph2 km/h from NW, gusts 7 mph11 km/h89%0%0
Sun 3aClear41°5° (likely 41°5° to 46°8°)41°5°0%1 mph2 km/h from NW, gusts 8 mph12 km/h89%0%0
Sun 4aClear41°5° (likely 40°4° to 46°8°)41°5°0%2 mph3 km/h from N, gusts 8 mph12 km/h89%0%0
Sun 5aClear39°4° (likely 39°4° to 47°8°)39°4°0%2 mph3 km/h from N, gusts 8 mph13 km/h96%0%0
Sun 6aClear40°4° (likely 39°4° to 47°8°)40°4°0%2 mph3 km/h from N, gusts 6 mph10 km/h89%0%0
Sun 7aSunny40°4° (likely 39°4° to 46°8°)40°4°0%2 mph3 km/h from N, gusts 6 mph9 km/h92%0%0
Sun 8aSunny41°5° (likely 41°5° to 46°8°)41°5°0%2 mph3 km/h from N, gusts 5 mph9 km/h89%0%0
Sun 9aSunny48°9° (likely 47°8° to 50°10°)48°9°0%2 mph3 km/h from N, gusts 5 mph9 km/h71%0%1
Sun 10aSunny52°11° (likely 52°11° to 56°13°)52°11°0%3 mph5 km/h from N, gusts 7 mph11 km/h63%0%2
Sun 11aSunny56°13° (likely 56°13° to 59°15°)56°13°0%3 mph5 km/h from N, gusts 6 mph10 km/h57%0%3
Sun 12pSunny59°15° (likely 59°15° to 61°16°)59°15°0%3 mph5 km/h from N, gusts 7 mph12 km/h49%0%4
Sun 1pSunny61°16° (likely 61°16° to 63°17°)61°16°0%3 mph5 km/h from NW, gusts 7 mph11 km/h44%0%4
Sun 2pSunny62°17° (likely 62°17° to 65°18°)62°17°0%3 mph5 km/h from NW, gusts 7 mph11 km/h43%0%4
Sun 3pSunny63°17° (likely 63°17° to 66°19°)63°17°0%3 mph5 km/h from NW, gusts 6 mph10 km/h39%0%3
Sun 4pSunny63°17° (likely 61°16° to 66°19°)63°17°0%2 mph3 km/h from W, gusts 6 mph9 km/h39%0%2
Sun 5pSunny62°17° (likely 60°16° to 63°17°)62°17°0%2 mph3 km/h from SW, gusts 7 mph11 km/h41%0%1
Sun 6pClear60°16° (likely 55°13° to 60°16°)60°16°0%2 mph3 km/h from SW, gusts 7 mph11 km/h46%0%0
Sun 7pClear56°13° (likely 51°11° to 56°13°)56°13°0%3 mph5 km/h from SW, gusts 8 mph12 km/h57%0%0
Sun 8pClear50°10° (likely 49°9° to 53°12°)49°9°0%3 mph5 km/h from SW, gusts 9 mph14 km/h74%0%0
Sun 9pClear49°9° (likely 47°8° to 52°11°)48°9°0%3 mph5 km/h from SW, gusts 9 mph14 km/h80%0%0
Sun 10pClear48°9° (likely 46°8° to 52°11°)48°9°0%2 mph3 km/h from SW, gusts 9 mph15 km/h83%1%0
Sun 11pClear48°9° (likely 46°8° to 51°11°)48°9°0%2 mph3 km/h from SW, gusts 9 mph15 km/h86%1%0
Mon 12aClear47°8° (likely 45°7° to 50°10°)47°8°0%2 mph3 km/h from SW, gusts 9 mph15 km/h86%1%0
Mon 1aClear46°8° (likely 44°7° to 50°10°)45°7°0%3 mph5 km/h from W, gusts 10 mph16 km/h89%1%0
Mon 2aClear46°8° (likely 44°7° to 49°9°)45°7°0%3 mph5 km/h from W, gusts 10 mph17 km/h89%2%0
Mon 3aClear44°7° (likely 44°7° to 48°9°)42°6°0%3 mph5 km/h from W, gusts 10 mph16 km/h93%1%0
Mon 4aClear44°7° (likely 43°6° to 48°9°)41°5°0%5 mph8 km/h from W, gusts 13 mph21 km/h93%0%0
Mon 5aClear43°6° (likely 42°6° to 47°8°)40°4°0%5 mph8 km/h from W, gusts 13 mph20 km/h96%0%0
Mon 6aClear42°6° (likely 42°6° to 46°8°)39°4°0%5 mph8 km/h from W, gusts 13 mph20 km/h96%0%0
Mon 7aSunny43°6° (likely 41°5° to 46°8°)40°4°0%5 mph8 km/h from W, gusts 12 mph20 km/h93%2%0
Mon 8aSunny44°7° (likely 41°5° to 47°8°)41°5°0%5 mph8 km/h from W, gusts 12 mph19 km/h89%1%0
Mon 9aSunny48°9° (likely 48°9° to 51°11°)46°8°0%5 mph8 km/h from W, gusts 12 mph19 km/h80%1%1
Mon 10aSunny53°12° (likely 53°12° to 56°13°)53°12°0%6 mph10 km/h from W, gusts 13 mph21 km/h71%12%2
Mon 11aSunny57°14° (likely 57°14° to 61°16°)57°14°0%6 mph10 km/h from W, gusts 12 mph19 km/h67%4%3
Mon 12pSunny61°16° (likely 61°16° to 63°17°)61°16°0%6 mph10 km/h from W, gusts 11 mph18 km/h60%7%4
Mon 1pSunny63°17° (likely 63°17° to 66°19°)63°17°0%7 mph11 km/h from W, gusts 11 mph17 km/h56%5%4
Mon 2pSunny65°18° (likely 64°18° to 67°19°)65°18°0%7 mph11 km/h from W, gusts 11 mph17 km/h54%0%4
Mon 3pSunny66°19° (likely 65°18° to 68°20°)66°19°0%7 mph11 km/h from W, gusts 11 mph18 km/h54%3%3
Mon 4pSunny66°19° (likely 65°18° to 69°21°)66°19°0%6 mph10 km/h from W, gusts 12 mph20 km/h54%4%2
Mon 5pSunny65°18° (likely 64°18° to 68°20°)65°18°0%6 mph10 km/h from W, gusts 11 mph17 km/h58%2%1

Days ahead

Shaded: typical range for these dates (1991–2020)
  1. Today, Oct 24. Cloudy. High 60°16°, low 39°4°. Typical 61°16° / 44°7°. Dry. Mostly agree.
    1. Evening

      6 PM–midnight

      Mostly clear, 48°9°

      Dry

    2. Overnight

      midnight–6 AM

      Clear, 39°4°

      Dry

    Official NWS forecast

    Tonight: Mostly clear, with a low around 39. Northwest wind around 2 mph.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    59°15°–62°17°
    Low, likely
    38°3°–43°6°
    Typical high / low
    61°16° / 44°7°
    Wind
    8 mph12 km/h, gusts 13 mph22 km/h
    UV peak
    4
  2. Tomorrow, Oct 25. Sunny. High 63°17°, low 42°6°. Typical 61°16° / 44°7°. Dry. Mostly agree.
    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, 43°6°

      Dry

    Official NWS forecast

    Day: Sunny, with a high near 63. Northwest wind around 3 mph.

    Night: Clear, with a low around 42. Southwest wind around 5 mph.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    63°17°–66°19°
    Low, likely
    39°4°–45°7°
    Typical high / low
    61°16° / 44°7°
    Wind
    6 mph10 km/h, gusts 13 mph22 km/h
    UV peak
    4
  3. Monday, Oct 26. Sunny. High 66°19°, low 48°9°. Typical 61°16° / 44°7°. Dry. Mostly agree.
    1. Morning

      6 AM–noon

      Sunny, 44°7°

      Dry

    2. Afternoon

      noon–6 PM

      Sunny, 66°19°

      Dry

    3. Evening

      6 PM–midnight

      Clear, 59°15°

      Dry

    4. Overnight

      midnight–6 AM

      Clear, 53°12°

      Dry

    Official NWS forecast

    Day: Sunny, with a high near 66. West wind around 7 mph.

    Night: Clear. Low around 48, with temperatures rising to around 50 overnight. Northwest wind 5 to 9 mph.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    65°18°–68°20°
    Low, likely
    41°5°–48°9°
    Typical high / low
    61°16° / 44°7°
    Wind
    8 mph13 km/h, gusts 20 mph31 km/h
    UV peak
    4
  4. Tuesday, Oct 27. Sunny. High 59°15°, low 41°5°. Typical 60°16° / 43°6°. Dry. Forecasts agree.
    1. Morning

      6 AM–noon

      Sunny, 51°11°

      Dry

    2. Afternoon

      noon–6 PM

      Sunny, 56°13°

      Dry

    3. Evening

      6 PM–midnight

      Clear, 49°10°

      Dry

    4. Overnight

      midnight–6 AM

      Clear, 46°8°

      Dry

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: Sunny, with a high near 59.

    Night: Mostly clear, with a low around 41.

    Forecasts agreeIndependent forecasts are close; the range is narrow.

    High, likely
    58°14°–59°15°
    Low, likely
    41°5°–50°10°
    Typical high / low
    60°16° / 43°6°
    Wind
    12 mph19 km/h, gusts 26 mph41 km/h
    UV peak
    4
  5. Wednesday, Oct 28. Mostly sunny. High 57°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, 59°15°

      Dry

    3. Evening

      6 PM–midnight

      Mostly clear, 51°11°

      Dry

    4. Overnight

      midnight–6 AM

      Cloudy, 51°11°

      Dry

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: Sunny, with a high near 57.

    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
    42°6°–47°8°
    Typical high / low
    60°16° / 43°6°
    Wind
    7 mph12 km/h, gusts 16 mph26 km/h
    UV peak
    4
  6. Thursday, Oct 29. Mostly sunny. High 64°18°, low 51°11°. Typical 60°16° / 43°6°. Dry. Mostly agree.
    1. Morning

      6 AM–noon

      Cloudy, 51°10°

      Dry

    2. Afternoon

      noon–6 PM

      Sunny, 63°17°

      Dry

    3. Evening

      6 PM–midnight

      Clear, 58°14°

      Dry

    4. Overnight

      midnight–6 AM

      Clear, 54°12°

      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 51.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    62°17°–65°18°
    Low, likely
    48°9°–52°11°
    Typical high / low
    60°16° / 43°6°
    Wind
    11 mph18 km/h, gusts 30 mph49 km/h
    UV peak
    4
  7. Friday, Oct 30. Mostly sunny. High 69°21°, low 50°10°. Typical 59°15° / 42°6°. Dry. Forecasts agree.
    1. Morning

      6 AM–noon

      Sunny, 54°12°

      Dry

    2. Afternoon

      noon–6 PM

      Sunny, 70°21°

      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 69.

    Night: Mostly clear, with a low around 50.

    Forecasts agreeIndependent forecasts are close; the range is narrow.

    High, likely
    68°20°–70°21°
    Low, likely
    50°10°–55°13°
    Typical high / low
    59°15° / 42°6°
    Wind
    9 mph14 km/h, gusts 25 mph41 km/h
    UV peak
    4
  8. Saturday, Oct 31. Partly sunny. High 65°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, 66°19°

      Dry

    3. Evening

      6 PM–midnight

      Cloudy, 56°14°

      Dry

    4. Overnight

      midnight–6 AM

      Cloudy, 55°13°

      Dry

    Hours this far out come from computer models only.

    Official NWS forecast

    Day: Mostly sunny, with a high near 65.

    Forecasts differIndependent forecasts disagree; expect changes and plan for the range.

    High, likely
    59°15°–68°20°
    Low, likely
    49°9°–54°12°
    Typical high / low
    59°15° / 42°6°
    Wind
    9 mph14 km/h, gusts 24 mph38 km/h
    UV peak
    4
  9. Sunday, Nov 1. Drizzle. High 64°18°, low 54°12°. Typical 58°14° / 42°6°. Rain 0.02 in0.5 mm, 30% chance. Forecasts differ.
    1. Morning

      6 AM–noon

      Cloudy, 56°13°

      Dry

    2. Afternoon

      noon–6 PM

      Cloudy, 64°18°

      Dry

    3. Evening

      6 PM–midnight

      Drizzle, 60°16°

      30% chance · 0.02 in0.6 mm

    4. Overnight

      midnight–6 AM

      Drizzle, 61°16°

      40% chance · 0.11 in2.7 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
    61°16°–70°21°
    Low, likely
    50°10°–57°14°
    Typical high / low
    58°14° / 42°6°
    Wind
    11 mph17 km/h, gusts 23 mph37 km/h
    UV peak
    2
  10. Monday, Nov 2. Drizzle. High 66°19°, low 59°15°. Typical 58°14° / 42°6°. Rain 0.85 in22 mm, 40% chance. Mostly agree.
    1. Morning

      6 AM–noon

      Showers, 62°17°

      40% chance · 0.33 in8.3 mm

    2. Afternoon

      noon–6 PM

      Showers, 66°19°

      30% chance · 0.31 in7.9 mm

    3. Evening

      6 PM–midnight

      Showers, 64°18°

      30% chance · 0.36 in9.2 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.

    Mostly agreeIndependent forecasts are fairly close; small surprises are possible.

    High, likely
    64°18°–69°21°
    Low, likely
    56°13°–65°18°
    Typical high / low
    58°14° / 42°6°
    Wind
    22 mph35 km/h, gusts 40 mph65 km/h

The outlook

  1. Today

    Dry, high 60°, low 39°.

  2. Tomorrow

    Dry, high 63°, low 42°, warming up.

  3. Monday

    Dry, high 66°, low 48°, warming up.

  4. Rest of week

    Mostly dry, highs 57–69°.

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

Long Island Sound near Bridgeport Harbor (IN MLLW)

22 mi
Below flood stage
Level
0.7 ft

Forecast peak 9.1 ft Tue 12 PM, minor flooding

Reading from Sat 5:06 PM · NWS gauge page

Flax Pond at Old Field (IN MLLW)

8.2 mi
Below flood stage
Level
4.3 ft

Reading from Sat 4:24 PM · NWS gauge page

Carlls River at Babylon

12 mi
Level
0.5 ft
Flow
15 cfs

Reading from Sat 5 PM · NWS gauge page

Great South Bay at Lindenhurst (IN MLLW)

15 mi
Below flood stage
Level
1.4 ft

Reading from Sat 4 PM · NWS gauge page

For your home

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

Heating this week

About 70% less heating than a typical week.

This week 28Typical 93

Heating degree days, base 65°F

Heat-pump hours, next 7 days

h below 47°F
21
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 8 hours are near freezing and damp, when outdoor units defrost more often.

Comfort

Dry air outside (dew point 28°F).

Open the windows?

Sun, 1:00 PM–6:00 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.

Normal high / low
61°16° / 44°7°
Forecast high / low
60°16° / 39°4°
Record high
74°23° in 1963
Record low
25°−4° in 1969

Last 7 days vs normal

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

  1. −6°−3°SunOct 18
  2. −4°−2°MonOct 19
  3. +3°+1°TueOct 20
  4. +2°+1°WedOct 21
  5. +4°+2°ThuOct 22
  6. −4°−2°FriOct 23
  7. —SatOct 24

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

Sun & moon

Sun

Sunrise 7:14 AM, sunset 5:59 PM.

Daylight
10 h 45 min
Losing 2 min 30 s a day; shortest Dec 21, 1 h 31 min less
Golden hour
5:21–6:16 PM
Morning 6:57–7:52 AM
Blue hour
6:16–6:27 PM
Morning 6:46–6:57 AM; first light 6:46 AM

Stars tonight? Fair

Mostly clear 10 PM–6:47 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 north from Smithtown. The highest point on the skyline is about 1,000 ft, 19 mi away.Skyline from USGS elevation data, heights drawn up to 6× taller. Sky, sun and moon as they are now.