Cornerstone Weather Forecast

    • 49
    • 54

    Rain Showers

    • 54
    • 59

    Rain Showers

    • 51
    • 58

    Rain Showers Likely

    • 45
    • 56

    Rain Showers

    • 39
    • 55

    Rain Showers Likely

    • 40
    • 53

    Rain Showers Likely

Today 31 Jan Carquinez Strait and Delta

A slight chance of rain Showers early in the Morning, then a chance of rain Showers late in the morning. Rain Showers in the afternoon. Patchy fog in the late morning and afternoon. Highs around 52. Southeast Winds up to 10 Mph.

Tonight 31 Jan Carquinez Strait and Delta

Patchy fog in the evening. Rain Showers. Lows around 49. Southeast Winds 10 to 15 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Cornerstone Temperature Statistics

January Temperature

Napa, Napa County Airport (7.5 miles)

  • Lowest 22 January, 2025

    28.9 °F
  • Average January

    48.9 °F
  • Highest 7 January, 2025

    70.6 °F

Climate (2020–Present)

Napa, Napa County Airport (7.5 miles)

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  • Average Low 2020–2025

    47 °F
  • Average 2020–2025

    58.1 °F
  • Average High 2020–2025

    70.7 °F
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