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.

Partly Cloudy

61°F

16°C

Humidity 77%
Wind Speed N 0 MPH
Barometer 29.92 in (1013.21 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 28 Aug 06:20 AM PDT
Extended Forecast for

4 Miles E Saint Helena CA

  • Today

    Today: A 20 percent chance of showers before 11am. Cloudy through mid morning, then gradual clearing, with a high near 83. Light and variable wind becoming south 9 to 14 mph in the afternoon.

    High: 83 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Tonight

    Tonight: Patchy fog after 1am. Otherwise, partly cloudy, with a low around 52. South wind 5 to 9 mph becoming calm in the evening.

    Low: 52 °F

    Mostly Clear
    then Patchy
    Fog

  • Saturday

    Saturday: Areas of fog before 9am. Otherwise, partly sunny, then gradually becoming sunny, with a high near 83. Calm wind becoming southwest around 6 mph in the afternoon.

    High: 83 °F

    Areas Fog
    then Sunny

  • Saturday Night

    Saturday Night: Patchy fog after 1am. Otherwise, mostly clear, with a low around 51. Southwest wind around 6 mph becoming calm in the evening.

    Low: 51 °F

    Clear then
    Patchy Fog

  • Sunday

    Sunday: Areas of fog before 9am. Otherwise, sunny, with a high near 84. Light and variable wind.

    High: 84 °F

    Areas Fog
    then Sunny

  • Sunday Night

    Sunday Night: Patchy fog after midnight. Otherwise, mostly clear, with a low around 50.

    Low: 50 °F

    Clear then
    Patchy Fog

  • Monday

    Monday: Areas of fog before 11am. Otherwise, mostly sunny, with a high near 77.

    High: 77 °F

    Areas Fog
    then Sunny

  • Monday Night

    Monday Night: Patchy fog after 11pm. Otherwise, partly cloudy, with a low around 48.

    Low: 48 °F

    Patchy Fog

  • Tuesday

    Tuesday: Areas of fog before 11am. Otherwise, partly sunny, with a high near 75.

    High: 75 °F

    Areas Fog
    then Mostly
    Sunny

Detailed Forecast

Today
A 20 percent chance of showers before 11am. Cloudy through mid morning, then gradual clearing, with a high near 83. Light and variable wind becoming south 9 to 14 mph in the afternoon.
Tonight
Patchy fog after 1am. Otherwise, partly cloudy, with a low around 52. South wind 5 to 9 mph becoming calm in the evening.
Saturday
Areas of fog before 9am. Otherwise, partly sunny, then gradually becoming sunny, with a high near 83. Calm wind becoming southwest around 6 mph in the afternoon.
Saturday Night
Patchy fog after 1am. Otherwise, mostly clear, with a low around 51. Southwest wind around 6 mph becoming calm in the evening.
Sunday
Areas of fog before 9am. Otherwise, sunny, with a high near 84. Light and variable wind.
Sunday Night
Patchy fog after midnight. Otherwise, mostly clear, with a low around 50.
Monday
Areas of fog before 11am. Otherwise, mostly sunny, with a high near 77.
Monday Night
Patchy fog after 11pm. Otherwise, partly cloudy, with a low around 48.
Tuesday
Areas of fog before 11am. Otherwise, partly sunny, with a high near 75.
Tuesday Night
Patchy fog after 10pm. Otherwise, mostly clear, with a low around 48.
Wednesday
Areas of fog. Otherwise, mostly sunny, with a high near 79.
Wednesday Night
Patchy fog. Otherwise, mostly clear, with a low around 49.
Thursday
Areas of fog. Otherwise, mostly sunny, with a high near 81.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles E Saint Helena CA
 38.5°N 122.4°W (Elev. 476 ft)
Last Update:
2:47 am PDT Aug 28, 2026
Forecast Valid:
6am PDT Aug 28, 2026-6pm PDT Sep 3, 2026
 
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Additional Resources

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