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Heavy Rain and Severe Thunderstorms Possible in the Lower Mississippi Valley & Southeast

A few severe thunderstorms are possible over Texas, the lower Mississippi Valley, and Southeast into Sunday. Locally heavy rainfall and flash flooding may also occur in these areas. Elsewhere, rain and higher elevation snow will develop from Idaho into western Montana by Sunday evening, followed by cooling temperatures and a changeover to snow for most of the northern Rockies by Monday. Read More >

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

A Few Clouds

52°F

11°C

Humidity 31%
Wind Speed N 12 mph
Barometer 30.40 in (1029.4 mb)
Dewpoint 22°F (-6°C)
Visibility 10.00 mi
Wind Chill48°F (9°C)
Last update 22 Apr 8:56 am EDT
Extended Forecast for

Holtsville NY

  • Today

    Today: Sunny, with a high near 62. West wind 7 to 10 mph.

    Sunny

    High: 62 °F

  • Tonight

    Tonight: Mostly clear, with a low around 40. Southwest wind around 6 mph becoming calm  in the evening.

    Mostly Clear

    Low: 40 °F

  • Monday

    Monday: Sunny, with a high near 61. Light and variable wind becoming south 6 to 11 mph in the morning.

    Sunny

    High: 61 °F

  • Monday
    Night

    Monday Night: Mostly clear, with a low around 41. South wind 5 to 9 mph becoming calm  after midnight.

    Mostly Clear

    Low: 41 °F

  • Tuesday

    Tuesday: Increasing clouds, with a high near 58. Southeast wind 5 to 13 mph.

    Increasing
    Clouds

    High: 58 °F

  • Tuesday
    Night

    Tuesday Night: Rain, mainly after 2am.  Low around 46. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

    Chance Rain
    then Rain

    Low: 46 °F

  • Wednesday

    Wednesday: Rain.  High near 55. Chance of precipitation is 90%.

    Rain

    High: 55 °F

  • Wednesday
    Night

    Wednesday Night: A 50 percent chance of showers.  Mostly cloudy, with a low around 47.

    Chance
    Showers

    Low: 47 °F

  • Thursday

    Thursday: A 30 percent chance of showers.  Mostly cloudy, with a high near 58.

    Chance
    Showers

    High: 58 °F

Detailed Forecast

Today
Sunny, with a high near 62. West wind 7 to 10 mph.
Tonight
Mostly clear, with a low around 40. Southwest wind around 6 mph becoming calm in the evening.
Monday
Sunny, with a high near 61. Light and variable wind becoming south 6 to 11 mph in the morning.
Monday Night
Mostly clear, with a low around 41. South wind 5 to 9 mph becoming calm after midnight.
Tuesday
Increasing clouds, with a high near 58. Southeast wind 5 to 13 mph.
Tuesday Night
Rain, mainly after 2am. Low around 46. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Wednesday
Rain. High near 55. Chance of precipitation is 90%.
Wednesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 47.
Thursday
A 30 percent chance of showers. Mostly cloudy, with a high near 58.
Thursday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 46.
Friday
Partly sunny, with a high near 60.
Friday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 45.
Saturday
A 30 percent chance of showers. Partly sunny, with a high near 58.
Click Map For Forecast
Point Forecast:
Holtsville NY
 40.82°N 73.05°W (Elev. 112 ft)
6:21 am EDT Apr 22, 2018
9am EDT Apr 22, 2018-6pm EDT Apr 28, 2018
 
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Additional Resources

Radar & Satellite Image

Northeast Radar Mosaic Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database