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Severe thunderstorms possible over the Mid Atlantic and Northeast U.S.

Severe thunderstorms may develop Monday afternoon and evening over portions of the Mid Atlantic and Northeast U.S. A few of the storms could contain damaging winds, large hail, and heavy rainfall. The severe weather threat will shift to the upper Midwest and Great Lakes by Tuesday and Wednesday of this week. Read More >

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Light Rain Fog/Mist

71°F

22°C

Humidity 96%
Wind Speed E 13 mph
Barometer 29.76 in (1007.6 mb)
Dewpoint 70°F (21°C)
Visibility 6.00 mi
Last update 24 Jul 8:56 am EDT
Extended Forecast for

Holtsville NY

  • Today

    Today: Showers likely and possibly a thunderstorm before 11am, then a chance of showers between 11am and noon, then a chance of showers and thunderstorms after noon.  Cloudy, with a steady temperature around 71. East wind 9 to 13 mph becoming north in the afternoon.  Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

    Showers
    Likely

    High: 71 °F

  • Tonight

    Tonight: A 30 percent chance of showers.  Cloudy, with a low around 65. Northeast wind 10 to 14 mph.

    Chance
    Showers

    Low: 65 °F

  • Tuesday

    Tuesday: A 20 percent chance of showers before 2pm.  Mostly cloudy, with a high near 74. Northeast wind 9 to 13 mph.

    Slight Chance
    Showers

    High: 74 °F

  • Tuesday
    Night

    Tuesday Night: Mostly cloudy, with a low around 63. East wind 9 to 11 mph.

    Mostly Cloudy

    Low: 63 °F

  • Wednesday

    Wednesday: Mostly sunny, with a high near 79. Northeast wind around 9 mph.

    Mostly Sunny

    High: 79 °F

  • Wednesday
    Night

    Wednesday Night: Partly cloudy, with a low around 66.

    Partly Cloudy

    Low: 66 °F

  • Thursday

    Thursday: Mostly cloudy, with a high near 84.

    Mostly Cloudy

    High: 84 °F

  • Thursday
    Night

    Thursday Night: A 40 percent chance of showers.  Cloudy, with a low around 70.

    Chance
    Showers

    Low: 70 °F

  • Friday

    Friday: A 50 percent chance of showers and thunderstorms.  Cloudy, with a high near 85.

    Chance
    T-storms

    High: 85 °F

Detailed Forecast

Today
Showers likely and possibly a thunderstorm before 11am, then a chance of showers between 11am and noon, then a chance of showers and thunderstorms after noon. Cloudy, with a steady temperature around 71. East wind 9 to 13 mph becoming north in the afternoon. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
Tonight
A 30 percent chance of showers. Cloudy, with a low around 65. Northeast wind 10 to 14 mph.
Tuesday
A 20 percent chance of showers before 2pm. Mostly cloudy, with a high near 74. Northeast wind 9 to 13 mph.
Tuesday Night
Mostly cloudy, with a low around 63. East wind 9 to 11 mph.
Wednesday
Mostly sunny, with a high near 79. Northeast wind around 9 mph.
Wednesday Night
Partly cloudy, with a low around 66.
Thursday
Mostly cloudy, with a high near 84.
Thursday Night
A 40 percent chance of showers. Cloudy, with a low around 70.
Friday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 85.
Friday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70.
Saturday
Partly sunny, with a high near 84.
Saturday Night
Partly cloudy, with a low around 69.
Sunday
Mostly sunny, with a high near 83.
Click Map For Forecast
Point Forecast:
Holtsville NY
 40.82°N 73.05°W (Elev. 112 ft)
6:54 am EDT Jul 24, 2017
9am EDT Jul 24, 2017-6pm EDT Jul 30, 2017
 
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Additional Resources

Radar & Satellite Image

Northeast Radar Mosaic Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database