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

Dangerous Heat and Possible Flooding

Dangerous heat will persist across the Southwest U.S. through Saturday with daytime highs of 110-115°F. Extreme Heat Warnings remain in effect. Dangerous heat will build across the southern Plains again beginning this weekend. Heavy to excessive rain over the Carolinas Friday may lead to isolated areas of flash flooding. Read More >

Current conditions at

Napa, Napa County Airport (KAPC)

Lat: 38.2075°NLon: 122.27944°WElev: 33.0ft.

Clear

68°F

20°C

Humidity 60%
Wind Speed W 8 MPH
Barometer 30.01 in (1016.26 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 28 Aug 12:35 PM PDT
Extended Forecast for

4 Miles SE Saint Helena CA

  • This Afternoon

    This Afternoon: A 20 percent chance of showers. Mostly cloudy, then gradually becoming sunny, with a high near 84. South southeast wind around 5 mph becoming calm.

    High: 84 °F

    Slight Chance
    Showers

  • Tonight

    Tonight: Patchy fog between 2am and 4am. Otherwise, increasing clouds, with a low around 52. South southeast wind around 5 mph becoming calm in the evening.

    Low: 52 °F

    Mostly Clear
    then Patchy
    Fog

  • Saturday

    Saturday: Patchy fog before 9am. Otherwise, partly sunny, then gradually becoming sunny, with a high near 85. Calm wind becoming southwest 5 to 7 mph in the afternoon.

    High: 85 °F

    Patchy Fog
    then Sunny

  • Saturday Night

    Saturday Night: Patchy fog after 2am. Otherwise, increasing clouds, with a low around 51. Southwest wind around 5 mph becoming calm in the evening.

    Low: 51 °F

    Mostly Clear
    then Patchy
    Fog

  • Sunday

    Sunday: Patchy fog before 9am. Otherwise, mostly sunny, with a high near 87. Calm wind.

    High: 87 °F

    Patchy Fog
    then Sunny

  • Sunday Night

    Sunday Night: Patchy fog after midnight. Otherwise, mostly clear, with a low around 51.

    Low: 51 °F

    Clear then
    Patchy Fog

  • Monday

    Monday: Areas of fog before 10am. Otherwise, mostly sunny, with a high near 81.

    High: 81 °F

    Areas Fog
    then Sunny

  • Monday Night

    Monday Night: Patchy fog after 2am. Otherwise, partly cloudy, with a low around 51.

    Low: 51 °F

    Mostly Clear
    then Patchy
    Fog

  • Tuesday

    Tuesday: Patchy fog before 8am. Otherwise, partly sunny, with a high near 77.

    High: 77 °F

    Patchy Fog
    then Mostly
    Sunny

Detailed Forecast

This Afternoon
A 20 percent chance of showers. Mostly cloudy, then gradually becoming sunny, with a high near 84. South southeast wind around 5 mph becoming calm.
Tonight
Patchy fog between 2am and 4am. Otherwise, increasing clouds, with a low around 52. South southeast wind around 5 mph becoming calm in the evening.
Saturday
Patchy fog before 9am. Otherwise, partly sunny, then gradually becoming sunny, with a high near 85. Calm wind becoming southwest 5 to 7 mph in the afternoon.
Saturday Night
Patchy fog after 2am. Otherwise, increasing clouds, with a low around 51. Southwest wind around 5 mph becoming calm in the evening.
Sunday
Patchy fog before 9am. Otherwise, mostly sunny, with a high near 87. Calm wind.
Sunday Night
Patchy fog after midnight. Otherwise, mostly clear, with a low around 51.
Monday
Areas of fog before 10am. Otherwise, mostly sunny, with a high near 81.
Monday Night
Patchy fog after 2am. Otherwise, partly cloudy, with a low around 51.
Tuesday
Patchy fog before 8am. Otherwise, partly sunny, with a high near 77.
Tuesday Night
Areas of fog after 11pm. Otherwise, partly cloudy, with a low around 51.
Wednesday
Areas of fog. Otherwise, mostly sunny, with a high near 80.
Wednesday Night
Patchy fog. Otherwise, mostly clear, with a low around 51.
Thursday
Areas of fog. Otherwise, mostly sunny, with a high near 81.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles SE Saint Helena CA
 38.45°N 122.41°W (Elev. 157 ft)
Last Update:
11:26 am PDT Aug 28, 2026
Forecast Valid:
12pm PDT Aug 28, 2026-6pm PDT Sep 3, 2026
 
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Additional Resources

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