Monthly outlook for Old Town San Diego, CA: average high 79.4°, average low 72.7°. That is 0.1° below the climate normal for August. Precipitation is expected on 1 day (about 0.1 inches), against a normal of 0 days and 0.1 inches. The warmest day looks like 10 August (86.6°), the coolest 10 August (69°).
79.4°/72.7°
Average high / low
−0.1°
Below normal
1 / 0
Wet days / normal
0.1 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
9 August – 18 August
78.6°
79.6°
-0.5°
19 August – 28 August
80.6°
80.1°
+0.3°
29 August – 7 September
at normal
81.2°
—
August records over 66 years
99.1°31 August 2017All-time high
55.8°9 August 2010All-time low
Climate normals and records are computed from the nearest reference point — San Diego (7 mi).
Mon, 1087° / 69°0
87 °
Old Town San Diego, Monday, 10 August
Mostly clear. High 87°, low 69°.
Pressure29.91 inHg
Wind8.6 mph SW
Humidity66%
Visibility6.2 mi
Dew point64°
Tue, 1178° / 73°0.01
78 °
Old Town San Diego, Tuesday, 11 August
Light rain. High 78°, low 73°.
Pressure29.97 inHg
Wind8.7 mph W
Humidity61%
Visibility6.2 mi
Dew point63°
Wed, 1277° / 72°0
77 °
Old Town San Diego, Wednesday, 12 August
Clear. High 77°, low 72°.
Pressure29.91 inHg
Wind9.6 mph W
Humidity62%
Visibility6.2 mi
Dew point63°
Thu, 1374° / 70°0
74 °
Old Town San Diego, Thursday, 13 August
Overcast. High 74°, low 70°.
Pressure29.91 inHg
Wind9.7 mph W
Humidity70%
Visibility—
Dew point62°
Fri, 1473° / 69°0
73 °
Old Town San Diego, Friday, 14 August
Overcast. High 73°, low 69°.
Pressure29.94 inHg
Wind9.3 mph W
Humidity68%
Visibility—
Dew point62°
Sat, 1576° / 71°0
76 °
Old Town San Diego, Saturday, 15 August
Overcast. High 76°, low 71°.
Pressure30.03 inHg
Wind11.7 mph W
Humidity67%
Visibility—
Dew point62°
Sun, 1678° / 73°0
78 °
Old Town San Diego, Sunday, 16 August
Overcast. High 78°, low 73°.
Pressure30.06 inHg
Wind11.7 mph W
Humidity62%
Visibility—
Dew point62°
Mon, 1778° / 73°0
78 °
Old Town San Diego, Monday, 17 August
Partly cloudy. High 78°, low 73°.
Pressure30.03 inHg
Wind13.1 mph NW
Humidity62%
Visibility—
Dew point63°
Tue, 1879° / 73°0.02
79 °
Old Town San Diego, Tuesday, 18 August
Light rain. High 79°, low 73°.
Pressure29.94 inHg
Wind10.8 mph W
Humidity63%
Visibility—
Dew point64°
Wed, 1980° / 74°0
80 °
Old Town San Diego, Wednesday, 19 August
Clear. High 80°, low 74°.
Pressure29.88 inHg
Wind11.4 mph S
Humidity61%
Visibility—
Dew point65°
Thu, 2082° / 74°0.06
82 °
Old Town San Diego, Thursday, 20 August
Light rain. High 82°, low 74°.
Pressure29.88 inHg
Wind8.3 mph SW
Humidity70%
Visibility—
Dew point67°
Fri, 2181° / 76°0
81 °
Old Town San Diego, Friday, 21 August
Partly cloudy. High 81°, low 76°.
Pressure29.85 inHg
Wind8.3 mph W
Humidity58%
Visibility—
Dew point65°
Sat, 2280° / 75°0
80 °
Old Town San Diego, Saturday, 22 August
Overcast. High 80°, low 75°.
Pressure29.88 inHg
Wind8.3 mph SW
Humidity62%
Visibility—
Dew point65°
Sun, 2379° / 74°0
79 °
Old Town San Diego, Sunday, 23 August
Clear. High 79°, low 74°.
Pressure29.91 inHg
Wind9.7 mph W
Humidity64%
Visibility—
Dew point66°
Mon, 2481° / 75°0
81 °
Old Town San Diego, Monday, 24 August
Clear. High 81°, low 75°.
Pressure29.88 inHg
Wind9.2 mph S
Humidity64%
Visibility—
Dew point67°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 2580° / 65°0.01
80 °
Old Town San Diego, Tuesday, 25 August
Climate normal for this date — 60-year average.
Average high80°
Average low65°
Average precipitation0.01 in
Chance of precipitation7%
Record high91° (1985)
Record low57° (1987)
Wed, 2681° / 65°0
81 °
Old Town San Diego, Wednesday, 26 August
Climate normal for this date — 60-year average.
Average high81°
Average low65°
Average precipitation0 in
Chance of precipitation3%
Record high93° (2021)
Record low58° (1987)
Thu, 2782° / 65°0
82 °
Old Town San Diego, Thursday, 27 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0 in
Chance of precipitation0%
Record high94° (2020)
Record low58° (1989)
Fri, 2882° / 65°0
82 °
Old Town San Diego, Friday, 28 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0 in
Chance of precipitation2%
Record high93° (2023)
Record low57° (1973)
Sat, 2982° / 65°0
82 °
Old Town San Diego, Saturday, 29 August
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0 in
Chance of precipitation3%
Record high96° (2023)
Record low58° (2010)
Sun, 3081° / 65°0
81 °
Old Town San Diego, Sunday, 30 August
Climate normal for this date — 60-year average.
Average high81°
Average low65°
Average precipitation0 in
Chance of precipitation3%
Record high93° (2017)
Record low58° (1964)
Mon, 3181° / 65°0
81 °
Old Town San Diego, Monday, 31 August
Climate normal for this date — 60-year average.
Average high81°
Average low65°
Average precipitation0 in
Chance of precipitation0%
Record high99° (2017)
Record low58° (2010)
Tue, 0180° / 65°0.01
80 °
Old Town San Diego, Tuesday, 1 September
Climate normal for this date — 60-year average.
Average high80°
Average low65°
Average precipitation0.01 in
Chance of precipitation3%
Record high98° (2017)
Record low58° (1964)
Wed, 0281° / 65°0
81 °
Old Town San Diego, Wednesday, 2 September
Climate normal for this date — 60-year average.
Average high81°
Average low65°
Average precipitation0 in
Chance of precipitation3%
Record high94° (2017)
Record low59° (1973)
Thu, 0381° / 65°0
81 °
Old Town San Diego, Thursday, 3 September
Climate normal for this date — 60-year average.
Average high81°
Average low65°
Average precipitation0 in
Chance of precipitation3%
Record high103° (1988)
Record low57° (1973)
Fri, 0482° / 65°0
82 °
Old Town San Diego, Friday, 4 September
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0 in
Chance of precipitation3%
Record high102° (1988)
Record low58° (1999)
Sat, 0582° / 65°0
82 °
Old Town San Diego, Saturday, 5 September
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0 in
Chance of precipitation2%
Record high103° (2020)
Record low58° (1970)
Sun, 0682° / 65°0
82 °
Old Town San Diego, Sunday, 6 September
Climate normal for this date — 60-year average.
Average high82°
Average low65°
Average precipitation0 in
Chance of precipitation7%
Record high103° (2020)
Record low57° (1973)
Mon, 0781° / 65°0.01
81 °
Old Town San Diego, Monday, 7 September
Climate normal for this date — 60-year average.
Average high81°
Average low65°
Average precipitation0.01 in
Chance of precipitation3%
Record high98° (2024)
Record low57° (1964)
About the monthly outlook
How accurate is a 30-day forecast?
The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Old Town San Diego, CA are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.
What does "above normal" mean?
We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.
Where do the 66-year records come from?
They are real temperature extremes recorded in Old Town San Diego, CA since 1960: the highest and lowest reading for each calendar date, with the year it happened.
How often is it updated?
The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.