National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Heat Wave and Severe Thunderstorms this Independence Day

A prolonged, dangerous heat wave will persist through the Independence Day weekend across the Ohio Valley, Midwest, and Mid-Atlantic. Numerous temperature records are expected. Clusters of severe thunderstorms will move across parts of the Allegheny Plateau into Mid Atlantic this Independence Day, with potential for widespread damaging winds. Additional severe thunderstorms in the Great Plains. Read More >

Hazardous Weather Conditions

Current conditions at

Reedsville / Mifflin (KRVL)

Lat: 40.68°NLon: 77.63°WElev: 820ft.

Fair

93°F

34°C

Humidity 47%
Wind Speed SW 9 mph
Barometer 29.94 in
Dewpoint 70°F (21°C)
Visibility 9.00 mi
Heat Index99°F (37°C)
Last update 4 Jul 3:15 pm EDT
Extended Forecast for

Lewistown PA

Heat Advisory July 4, 03:20pm until July 4, 08:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory July 4, 03:20pm until July 4, 08:00pm

    NOW until 8:00pm Sat

    Heat Advisory

  • Independence Day

    High: 95 °F

    Hot

  • Tonight

    Tonight: A chance of showers and thunderstorms before midnight, then a slight chance of showers between midnight and 1am. Some of the storms could be severe. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 68. Light and variable wind. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 68 °F

    Severe
    Thunderstorms
    and Patchy
    Fog

  • Sunday

    Sunday: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 2pm. High near 88. Calm wind. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    High: 88 °F

    Slight Chance
    T-storms then
    Showers

  • Sunday Night

    Sunday Night: Showers and thunderstorms before 3am, then showers and possibly a thunderstorm, mainly after 3am. Patchy fog after 9pm. Low around 64. Calm wind. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.

    Low: 64 °F

    Showers and
    Patchy Fog

  • Monday

    Monday: Showers and possibly a thunderstorm. Areas of fog before 1pm. High near 79. Calm wind. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

    High: 79 °F

    Showers and
    Areas Fog
    then T-storms
    and Patchy
    Fog

  • Monday Night

    Monday Night: Showers and possibly a thunderstorm. Low around 62. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 62 °F

    T-storms then
    Showers

  • Tuesday

    Tuesday: A chance of showers, with thunderstorms also possible after 2pm. Mostly cloudy, with a high near 80. Chance of precipitation is 50%.

    High: 80 °F

    Chance
    Showers then
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: A chance of thunderstorms before 8pm. Mostly cloudy, with a low around 61. Chance of precipitation is 30%.

    Low: 61 °F

    Chance
    T-storms then
    Mostly Cloudy

Detailed Forecast

Independence Day
Sunny and hot, with a high near 95. Heat index values as high as 102. West wind around 6 mph.
Tonight
A chance of showers and thunderstorms before midnight, then a slight chance of showers between midnight and 1am. Some of the storms could be severe. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 68. Light and variable wind. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 2pm. High near 88. Calm wind. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Sunday Night
Showers and thunderstorms before 3am, then showers and possibly a thunderstorm, mainly after 3am. Patchy fog after 9pm. Low around 64. Calm wind. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.
Monday
Showers and possibly a thunderstorm. Areas of fog before 1pm. High near 79. Calm wind. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.
Monday Night
Showers and possibly a thunderstorm. Low around 62. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Tuesday
A chance of showers, with thunderstorms also possible after 2pm. Mostly cloudy, with a high near 80. Chance of precipitation is 50%.
Tuesday Night
A chance of thunderstorms before 8pm. Mostly cloudy, with a low around 61. Chance of precipitation is 30%.
Wednesday
Mostly sunny, with a high near 85.
Wednesday Night
Partly cloudy, with a low around 63.
Thursday
Mostly sunny, with a high near 89.
Thursday Night
Partly cloudy, with a low around 66.
Friday
Showers likely and possibly a thunderstorm. Partly sunny, with a high near 87. Chance of precipitation is 60%.
Friday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 64. Chance of precipitation is 60%.
Saturday
A chance of showers and thunderstorms. Partly sunny, with a high near 86.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Lewistown PA
 40.61°N 77.57°W (Elev. 515 ft)
Last Update:
2:23 pm EDT Jul 4, 2026
Forecast Valid:
3pm EDT Jul 4, 2026-6pm EDT Jul 11, 2026
 
Forecast Discussion
 
Get as KML Get as XML

Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation