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Grassmont Reservoir, CA 7-Day Night Weather Forecast
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Grassmont Reservoir, CA Weather Forecast
Grassmont Reservoir, CA Weather Forecast Date: 1148 AM PDT Sun Aug 23 2026
The area/counties/county of: San Diego County Valleys, including the cities of: Escondido, El Cajon, San Marcos, La Mesa, Santee, and Poway.or toggle through each period.
Tonight... Mostly clear this evening...Becoming partly cloudy. Lows 66 to 73. Areas of winds west to 10 mph this evening becoming light.
Monday... Mostly sunny. Highs 89 to 94 in the western valleys to 94 to 99 near the foothills. Light winds becoming west 10 mph in the afternoon.
Monday Night... Mostly clear. Lows 68 to 72. Light winds.
Tuesday... Patchy fog in the morning. Mostly sunny. Local visibility one quarter mile or less at times in the morning. Highs 91 to 96 in the western valleys to 96 to 101 near the foothills. Light winds becoming west 10 mph in the afternoon.
Tuesday Night... Mostly clear. Patchy fog overnight. Local visibility one quarter mile or less at times overnight. Lows 69 to 75. Areas of winds west to 10 mph in the evening becoming light.
Wednesday... Patchy fog in the morning. Mostly sunny. Local visibility one quarter mile or less at times in the morning. Highs 93 to 98 in the western valleys to 97 to 102 near the foothills.
Wednesday Night... Mostly clear. Lows 72 to 76.
Thursday... Partly cloudy in the morning...Becoming mostly sunny. Highs 94 to 99 in the western valleys to 98 to 103 near the foothills.
Thursday Night... Mostly clear in the evening...Becoming partly cloudy. Lows 72 to 76.
Friday... Partly cloudy. Highs 94 to 99 in the western valleys to 98 to 103 near the foothills.
Friday Night... Partly cloudy in the evening...Becoming mostly clear. Lows 70 to 74.
Saturday... Mostly sunny. Highs 93 to 98 in the western valleys to 97 to 102 near the foothills.
Saturday Night... Mostly clear. Lows 68 to 73.
POP = Probability of Precipitation
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