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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.

Fair

79°F

26°C

Humidity 67%
Wind Speed W 7 mph
Barometer 29.86 in (1011.1 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Heat Index81°F (27°C)
Last update 21 Jul 12:56 am EDT
Extended Forecast for

Stony Brook NY

Heat Advisory until July 21, 06:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory until July 21, 06:00pm

    NOW until
    6:00pm Fri

    Heat Advisory

  • Overnight

    Overnight: Mostly cloudy, with a steady temperature around 78. West wind 5 to 8 mph.

    Mostly Cloudy

    Low: 78 °F

  • Friday

    Friday: Mostly sunny, with a high near 91. West wind 8 to 11 mph, with gusts as high as 21 mph.

    Mostly Sunny

    High: 91 °F

  • Friday
    Night

    Friday Night: Partly cloudy, with a low around 71. West wind 5 to 9 mph becoming north after midnight.

    Partly Cloudy

    Low: 71 °F

  • Saturday

    Saturday: A 20 percent chance of showers and thunderstorms after 2pm.  Partly sunny, with a high near 87. Light and variable wind becoming southwest 5 to 7 mph in the afternoon.

    Partly Sunny
    then Slight
    Chance
    T-storms

    High: 87 °F

  • Saturday
    Night

    Saturday Night: A 30 percent chance of showers and thunderstorms, mainly after 8pm.  Mostly cloudy, with a low around 74. South wind 5 to 10 mph.

    Chance
    T-storms

    Low: 74 °F

  • Sunday

    Sunday: A chance of showers, with thunderstorms also possible after 2pm. Some of the storms could produce heavy rain.  Mostly cloudy, with a high near 82. Chance of precipitation is 50%.

    Chance
    Showers then
    Heavy Rain

    High: 82 °F

  • Sunday
    Night

    Sunday Night: A chance of showers and thunderstorms. Some of the storms could produce heavy rain.  Mostly cloudy, with a low around 72. Chance of precipitation is 50%.

    Heavy Rain
    then Chance
    Showers

    Low: 72 °F

  • Monday

    Monday: A 40 percent chance of showers and thunderstorms.  Partly sunny, with a high near 83.

    Chance
    T-storms

    High: 83 °F

Detailed Forecast

Overnight
Mostly cloudy, with a steady temperature around 78. West wind 5 to 8 mph.
Friday
Mostly sunny, with a high near 91. West wind 8 to 11 mph, with gusts as high as 21 mph.
Friday Night
Partly cloudy, with a low around 71. West wind 5 to 9 mph becoming north after midnight.
Saturday
A 20 percent chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 87. Light and variable wind becoming southwest 5 to 7 mph in the afternoon.
Saturday Night
A 30 percent chance of showers and thunderstorms, mainly after 8pm. Mostly cloudy, with a low around 74. South wind 5 to 10 mph.
Sunday
A chance of showers, with thunderstorms also possible after 2pm. Some of the storms could produce heavy rain. Mostly cloudy, with a high near 82. Chance of precipitation is 50%.
Sunday Night
A chance of showers and thunderstorms. Some of the storms could produce heavy rain. Mostly cloudy, with a low around 72. Chance of precipitation is 50%.
Monday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 83.
Monday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 69.
Tuesday
Partly sunny, with a high near 80.
Tuesday Night
Partly cloudy, with a low around 66.
Wednesday
Mostly sunny, with a high near 80.
Wednesday Night
Partly cloudy, with a low around 68.
Thursday
Mostly sunny, with a high near 80.
Click Map For Forecast
Point Forecast:
Stony Brook NY
 40.92°N 73.12°W (Elev. 112 ft)
10:16 pm EDT Jul 20, 2017
1am EDT Jul 21, 2017-6pm EDT Jul 27, 2017
 
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Additional Resources

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