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

Strong Storms and Heavy Rainfall Threats; Dangerous Heat for Southern Plains into the Southwest

Thunderstorms, some severe, will impact areas of the Plains into the Midwest today. Rainfall can be locally heavy as well from these storms with isolated instances of flash flooding. Monsoonal flow will enhance rainfall across the Four Corners into the central Rockies today. Meanwhile, summer heat continues for the southern Plains, Southwest into southern California. Read More >

Current conditions at

Napa, Napa County Airport (KAPC)

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

Clear

81°F

27°C

Humidity 51%
Wind Speed SSW 12 MPH
Barometer 29.97 in (1014.9 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 25 Aug 04:20 PM PDT
Extended Forecast for

4 Miles E Saint Helena CA

  • Tonight

    Tonight: Partly cloudy, with a low around 56. West southwest wind 5 to 7 mph becoming calm in the evening.

    Low: 56 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Partly sunny, then gradually becoming sunny, with a high near 92. Calm wind becoming west southwest 5 to 8 mph in the afternoon.

    High: 92 °F

    Becoming
    Sunny

  • Wednesday Night

    Wednesday Night: Increasing clouds, with a low around 59. West wind 5 to 7 mph becoming calm in the evening.

    Low: 59 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Mostly sunny, with a high near 92. Calm wind becoming west southwest around 5 mph in the afternoon.

    High: 92 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 59. West southwest wind around 6 mph becoming calm in the evening.

    Low: 59 °F

    Mostly Cloudy

  • Friday

    Friday: Partly sunny, with a high near 87.

    High: 87 °F

    Partly Sunny

  • Friday Night

    Friday Night: Patchy fog after 1am. Otherwise, mostly clear, with a low around 51.

    Low: 51 °F

    Mostly Clear
    then Patchy
    Fog

  • Saturday

    Saturday: Areas of fog before 9am. Otherwise, mostly sunny, with a high near 86.

    High: 86 °F

    Areas Fog
    then Sunny

  • Saturday Night

    Saturday Night: Patchy fog after 11pm. Otherwise, mostly clear, with a low around 49.

    Low: 49 °F

    Patchy Fog

Detailed Forecast

Tonight
Partly cloudy, with a low around 56. West southwest wind 5 to 7 mph becoming calm in the evening.
Wednesday
Partly sunny, then gradually becoming sunny, with a high near 92. Calm wind becoming west southwest 5 to 8 mph in the afternoon.
Wednesday Night
Increasing clouds, with a low around 59. West wind 5 to 7 mph becoming calm in the evening.
Thursday
Mostly sunny, with a high near 92. Calm wind becoming west southwest around 5 mph in the afternoon.
Thursday Night
Mostly cloudy, with a low around 59. West southwest wind around 6 mph becoming calm in the evening.
Friday
Partly sunny, with a high near 87.
Friday Night
Patchy fog after 1am. Otherwise, mostly clear, with a low around 51.
Saturday
Areas of fog before 9am. Otherwise, mostly sunny, with a high near 86.
Saturday Night
Patchy fog after 11pm. Otherwise, mostly clear, with a low around 49.
Sunday
Areas of fog before 10am. Otherwise, mostly sunny, with a high near 82.
Sunday Night
Areas of fog. Otherwise, mostly clear, with a low around 48.
Monday
Areas of fog. Otherwise, mostly sunny, with a high near 78.
Monday Night
Areas of fog. Otherwise, partly cloudy, with a low around 47.
Tuesday
Areas of fog. Otherwise, mostly sunny, with a high near 80.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles E Saint Helena CA
 38.5°N 122.4°W (Elev. 476 ft)
Last Update:
1:26 pm PDT Aug 25, 2026
Forecast Valid:
4pm PDT Aug 25, 2026-6pm PDT Sep 1, 2026
 
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