Heat Wave Expands to the East Coast; Flash Flooding Likely in the Central Plains into the Midwest; Severe Thunderstorms in the Northeast

Dangerous, prolonged heat is ongoing in the Mid-South to Mid-Mississippi Valley and heat expands into the Northeast for a brief period today. Widely scattered instances of flash flooding due to heavy rains are forecast from northeast Kansas to much of Indiana. Scattered strong to severe thunderstorms are possible across parts of New England, northern Mid-Atlantic, and North Dakota. Read More >

Current conditions at

Harlan, Harlan Municipal Airport (KHNR)

Lat: 41.58°NLon: 95.34°WElev: 1230ft.

Fair

88°F

31°C

Humidity 79%
Wind Speed S 8 mph
Barometer 29.98 in
Dewpoint 81°F (27°C)
Visibility 10.00 mi
Heat Index106°F (41°C)
Last update 27 Jul 12:35 pm CDT
Extended Forecast for

Portsmouth IA

Heat Advisory until July 28, 12:00pm
Extreme Heat Warning July 28, 12:00pm until July 28, 08:00pm
Click here for hazard details and duration
Heat Advisory
Extreme Heat Warning
  •  
    Heat Advisory until July 28, 12:00pm

    NOW until 12:00pm Mon

    Heat Advisory

  • This Afternoon

    High: 93 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 74. South wind 7 to 9 mph, with gusts as high as 16 mph.

    Low: 74 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 95. Heat index values as high as 110. South wind 6 to 8 mph.

    High: 95 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 73. South wind 5 to 7 mph.

    Low: 73 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 91. South southeast wind 5 to 8 mph.

    High: 91 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Showers and thunderstorms likely, mainly after 1am.  Mostly cloudy, with a low around 67. East northeast wind 6 to 8 mph.  Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 67 °F

    Slight Chance
    T-storms then
    T-storms
    Likely

  • Wednesday

    Wednesday: Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm.  Mostly cloudy, with a high near 76. Northeast wind 7 to 11 mph, with gusts as high as 18 mph.  Chance of precipitation is 60%.

    High: 76 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms.  Mostly cloudy, with a low around 62. Northeast wind 8 to 10 mph, with gusts as high as 18 mph.

    Low: 62 °F

    Chance
    Showers

Detailed Forecast

This Afternoon
Sunny, with a high near 93. Heat index values as high as 107. South wind around 10 mph, with gusts as high as 17 mph.
Tonight
Mostly clear, with a low around 74. South wind 7 to 9 mph, with gusts as high as 16 mph.
Monday
Sunny, with a high near 95. Heat index values as high as 110. South wind 6 to 8 mph.
Monday Night
Partly cloudy, with a low around 73. South wind 5 to 7 mph.
Tuesday
Mostly sunny, with a high near 91. South southeast wind 5 to 8 mph.
Tuesday Night
Showers and thunderstorms likely, mainly after 1am. Mostly cloudy, with a low around 67. East northeast wind 6 to 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Wednesday
Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 76. Northeast wind 7 to 11 mph, with gusts as high as 18 mph. Chance of precipitation is 60%.
Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 62. Northeast wind 8 to 10 mph, with gusts as high as 18 mph.
Thursday
A slight chance of showers. Partly sunny, with a high near 73. East wind 9 to 11 mph, with gusts as high as 20 mph.
Thursday Night
A slight chance of showers after 1am. Mostly cloudy, with a low around 57. East wind 6 to 9 mph.
Friday
A slight chance of showers. Partly sunny, with a high near 71. East wind 7 to 10 mph, with gusts as high as 18 mph.
Friday Night
A slight chance of showers. Mostly cloudy, with a low around 57. East wind 6 to 9 mph.
Saturday
Partly sunny, with a high near 75. Southeast wind 6 to 10 mph, with gusts as high as 17 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Portsmouth IA
 41.65°N 95.53°W (Elev. 1250 ft)
12:44 pm CDT Jul 27, 2025
12pm CDT Jul 27, 2025-6pm CDT Aug 2, 2025
 
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Additional Resources

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