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Areas of Severe Thunderstorms and Heat

Scattered severe thunderstorms and excessive rainfall are possible today in the Mid Atlantic, posing a risk for damaging winds and isolated flash flooding. Extreme Heat Warnings are in effect today for northeast Texas into southern Oklahoma and Arkansas. Extreme Heat Warnings are also in effect for the Desert Southwest today into Sunday. Read More >

Hazardous Weather Conditions

Current conditions at

Pottstown, Pottstown Limerick Airport (KPTW)

Lat: 40.24°NLon: 75.55°WElev: 288ft.

Mostly Cloudy

77°F

25°C

Humidity 77%
Wind Speed Vrbl 3 mph
Barometer 29.98 in (1014.7 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 20 Aug 1:54 pm EDT
Extended Forecast for

Collegeville PA

Flood Watch August 20, 02:00pm until August 21, 02:00am
Click here for hazard details and duration
Flood Watch
  •  
    Flood Watch August 20, 02:00pm until August 21, 02:00am

    NOW until 2:00am Fri

    Flood Watch

  • This Afternoon

    High: 81 °F

    Heavy Rain

  • Tonight

    Tonight: Showers and thunderstorms, mainly before 9pm. Some of the storms could produce heavy rainfall. Low around 61. North wind around 5 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 61 °F

    Heavy Rain
    then Mostly
    Cloudy

  • Friday

    Friday: Partly sunny, with a high near 82. Northeast wind around 5 mph.

    High: 82 °F

    Partly Sunny

  • Friday Night

    Friday Night: A chance of showers, mainly after 5am. Increasing clouds, with a low around 64. Calm wind. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

    Low: 64 °F

    Partly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: Showers likely, with thunderstorms also possible after 2pm. Mostly cloudy, with a high near 80. East wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 80 °F

    Showers
    Likely

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms before 2am. Mostly cloudy, with a low around 64. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 64 °F

    Chance
    T-storms then
    Chance
    Showers

  • Sunday

    Sunday: A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 83. Chance of precipitation is 40%.

    High: 83 °F

    Partly Sunny
    then Chance
    T-storms

  • Sunday Night

    Sunday Night: A chance of showers and thunderstorms before 8pm. Mostly clear, with a low around 60. Chance of precipitation is 30%.

    Low: 60 °F

    Chance
    T-storms then
    Clear

Detailed Forecast

This Afternoon
Showers and thunderstorms. Some of the storms could produce heavy rainfall. High near 81. Southeast wind around 5 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.
Tonight
Showers and thunderstorms, mainly before 9pm. Some of the storms could produce heavy rainfall. Low around 61. North wind around 5 mph. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.
Friday
Partly sunny, with a high near 82. Northeast wind around 5 mph.
Friday Night
A chance of showers, mainly after 5am. Increasing clouds, with a low around 64. Calm wind. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.
Saturday
Showers likely, with thunderstorms also possible after 2pm. Mostly cloudy, with a high near 80. East wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Saturday Night
A chance of showers and thunderstorms before 2am. Mostly cloudy, with a low around 64. Chance of precipitation is 30%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday
A chance of showers and thunderstorms after 2pm. Partly sunny, with a high near 83. Chance of precipitation is 40%.
Sunday Night
A chance of showers and thunderstorms before 8pm. Mostly clear, with a low around 60. Chance of precipitation is 30%.
Monday
Sunny, with a high near 80.
Monday Night
Mostly clear, with a low around 58.
Tuesday
Sunny, with a high near 81.
Tuesday Night
Mostly clear, with a low around 60.
Wednesday
A chance of showers. Mostly sunny, with a high near 85. Chance of precipitation is 30%.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Collegeville PA
 40.17°N 75.46°W (Elev. 98 ft)
Last Update:
1:00 pm EDT Aug 20, 2026
Forecast Valid:
2pm EDT Aug 20, 2026-6pm EDT Aug 26, 2026
 
Forecast Discussion
 
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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