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Severe Thunderstorms With Heavy Rain Possible In The Upper Midwest; Excessive Heat For Central U.S.

Several rounds of strong to severe thunderstorms will be possible from the northern Plains and upper Midwest to the Great Lakes through Friday. Damaging winds, large hail, and flooding will be the primary threats with these storms. Excessive heat will grip the central Plains with heat indices approaching 105 to 110 degrees. Very hot and humid conditions are likely to expand into the Mid Atlantic. Read More >

Current conditions at

Islip, Long Island Mac Arthur Airport (KISP)

Lat: 40.79°NLon: 73.1°WElev: 98ft.

Mostly Cloudy

90°F

32°C

Humidity 39%
Wind Speed NW 8 mph
Barometer 29.85 in (1010.5 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Heat Index90°F (32°C)
Last update 21 Jul 6:56 pm EDT
Extended Forecast for

Islip NY

  • Tonight

    Tonight: Partly cloudy, with a low around 74. Southwest wind 5 to 9 mph becoming light west  after midnight.

    Partly Cloudy

    Low: 74 °F

  • Saturday

    Saturday: Mostly sunny, with a high near 88. North wind 5 to 8 mph becoming southwest in the afternoon.

    Mostly Sunny

    High: 88 °F

  • Saturday
    Night

    Saturday Night: Showers and thunderstorms likely, mainly after 1am. Some of the storms could produce gusty winds and heavy rain.  Mostly cloudy, with a low around 74. Light and variable wind becoming north 5 to 9 mph after midnight.  Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Heavy Rain

    Low: 74 °F

  • Sunday

    Sunday: A 40 percent chance of showers and thunderstorms, mainly before 1pm.  Mostly cloudy, with a high near 78. Northeast wind around 11 mph.

    Chance
    T-storms

    High: 78 °F

  • Sunday
    Night

    Sunday Night: A 40 percent chance of showers and thunderstorms.  Increasing clouds, with a low around 67. East wind around 11 mph.

    Chance
    T-storms

    Low: 67 °F

  • Monday

    Monday: A 50 percent chance of showers and thunderstorms.  Cloudy, with a high near 82.

    Chance
    T-storms

    High: 82 °F

  • Monday
    Night

    Monday Night: A 30 percent chance of showers and thunderstorms.  Cloudy, with a low around 68.

    Chance
    T-storms

    Low: 68 °F

  • Tuesday

    Tuesday: Mostly sunny, with a high near 80.

    Mostly Sunny

    High: 80 °F

  • Tuesday
    Night

    Tuesday Night: Mostly clear, with a low around 65.

    Mostly Clear

    Low: 65 °F

Detailed Forecast

Tonight
Partly cloudy, with a low around 74. Southwest wind 5 to 9 mph becoming light west after midnight.
Saturday
Mostly sunny, with a high near 88. North wind 5 to 8 mph becoming southwest in the afternoon.
Saturday Night
Showers and thunderstorms likely, mainly after 1am. Some of the storms could produce gusty winds and heavy rain. Mostly cloudy, with a low around 74. Light and variable wind becoming north 5 to 9 mph after midnight. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday
A 40 percent chance of showers and thunderstorms, mainly before 1pm. Mostly cloudy, with a high near 78. Northeast wind around 11 mph.
Sunday Night
A 40 percent chance of showers and thunderstorms. Increasing clouds, with a low around 67. East wind around 11 mph.
Monday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 82.
Monday Night
A 30 percent chance of showers and thunderstorms. Cloudy, with a low around 68.
Tuesday
Mostly sunny, with a high near 80.
Tuesday Night
Mostly clear, with a low around 65.
Wednesday
Mostly sunny, with a high near 80.
Wednesday Night
Mostly cloudy, with a low around 69.
Thursday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 81.
Thursday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70.
Friday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 84.
Click Map For Forecast
Point Forecast:
Islip NY
 40.73°N 73.22°W (Elev. 7 ft)
3:38 pm EDT Jul 21, 2017
7pm EDT Jul 21, 2017-6pm EDT Jul 28, 2017
 
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Additional Resources

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