Monthly outlook for Simi Valley, CA: average high 78.9°, average low 57.5°. That is 0.3° above the climate normal for October. Precipitation is expected on 2 days (about 1.6 inches), against a normal of 1 days and 0.4 inches. The warmest day looks like 16 October (89.6°), the coolest 21 October (48.9°).
78.9°/57.5°
Average high / low
+0.3°
Above normal
2 / 1
Wet days / normal
1.6 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
13 October – 22 October
81.7°
79.1°
+1.4°
23 October – 1 November
74.3°
76.2°
-1°
2 November – 11 November
at normal
73.2°
—
October records over 66 years
106.2°1 October 2020All-time high
35.1°29 October 1971All-time low
Wed, 1481° / 56°0
81 °
Simi Valley, Wednesday, 14 October
Clear. High 81°, low 56°.
Pressure30.06 inHg
Wind9.4 mph NE
Humidity17%
Visibility6.2 mi
Dew point25°
Thu, 1588° / 63°0
88 °
Simi Valley, Thursday, 15 October
Clear. High 88°, low 63°.
Pressure30.03 inHg
Wind18.6 mph NE
Humidity15%
Visibility6.2 mi
Dew point28°
Fri, 1690° / 72°0
90 °
Simi Valley, Friday, 16 October
Clear. High 90°, low 72°.
Pressure30.00 inHg
Wind20 mph NE
Humidity17%
Visibility6.2 mi
Dew point36°
Sat, 1789° / 70°0
89 °
Simi Valley, Saturday, 17 October
Clear. High 89°, low 70°.
Pressure30.00 inHg
Wind14.3 mph NE
Humidity18%
Visibility—
Dew point36°
Sun, 1889° / 64°0
89 °
Simi Valley, Sunday, 18 October
Clear. High 89°, low 64°.
Pressure29.97 inHg
Wind9.1 mph SW
Humidity21%
Visibility—
Dew point37°
Mon, 1982° / 60°0
82 °
Simi Valley, Monday, 19 October
Clear. High 82°, low 60°.
Pressure29.94 inHg
Wind12.8 mph SW
Humidity33%
Visibility—
Dew point45°
Tue, 2069° / 52°0
69 °
Simi Valley, Tuesday, 20 October
Clear. High 69°, low 52°.
Pressure29.83 inHg
Wind22.4 mph N
Humidity30%
Visibility—
Dew point32°
Wed, 2175° / 49°0
75 °
Simi Valley, Wednesday, 21 October
Clear. High 75°, low 49°.
Pressure29.94 inHg
Wind10.1 mph W
Humidity20%
Visibility—
Dew point24°
Thu, 2279° / 53°0
79 °
Simi Valley, Thursday, 22 October
Clear. High 79°, low 53°.
Pressure30.03 inHg
Wind13 mph W
Humidity14%
Visibility—
Dew point19°
Fri, 2384° / 55°0
84 °
Simi Valley, Friday, 23 October
Clear. High 84°, low 55°.
Pressure29.94 inHg
Wind9.1 mph W
Humidity14%
Visibility—
Dew point21°
Sat, 2479° / 56°0
79 °
Simi Valley, Saturday, 24 October
Clear. High 79°, low 56°.
Pressure30.09 inHg
Wind30.5 mph NE
Humidity15%
Visibility—
Dew point21°
Sun, 2581° / 56°0
81 °
Simi Valley, Sunday, 25 October
Clear. High 81°, low 56°.
Pressure30.00 inHg
Wind24.9 mph NE
Humidity10%
Visibility—
Dew point13°
Mon, 2674° / 54°0.02
74 °
Simi Valley, Monday, 26 October
Light rain. High 74°, low 54°.
Pressure29.71 inHg
Wind11.6 mph S
Humidity25%
Visibility—
Dew point32°
Tue, 2761° / 56°1.47
61 °
Simi Valley, Tuesday, 27 October
Rain. High 61°, low 56°.
Pressure29.68 inHg
Wind23.5 mph SE
Humidity76%
Visibility—
Dew point51°
Wed, 2867° / 55°0.08
67 °
Simi Valley, Wednesday, 28 October
Light rain. High 67°, low 55°.
Pressure29.97 inHg
Wind10.9 mph SE
Humidity63%
Visibility—
Dew point50°
From day 17 onward the outlook is built from 60-year climate statistics
Thu, 2975° / 53°0.02
75 °
Simi Valley, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high75°
Average low53°
Average precipitation0.02 in
Chance of precipitation5%
Record high90° (1965)
Record low35° (1971)
Fri, 3074° / 53°0.06
74 °
Simi Valley, Friday, 30 October
Climate normal for this date — 60-year average.
Average high74°
Average low53°
Average precipitation0.06 in
Chance of precipitation18%
Record high91° (2025)
Record low36° (1971)
Sat, 3175° / 52°0.02
75 °
Simi Valley, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high75°
Average low52°
Average precipitation0.02 in
Chance of precipitation5%
Record high91° (1966)
Record low39° (1972)
Sun, 0176° / 53°0.04
76 °
Simi Valley, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high76°
Average low53°
Average precipitation0.04 in
Chance of precipitation8%
Record high91° (1997)
Record low42° (2000)
Mon, 0276° / 52°0.01
76 °
Simi Valley, Monday, 2 November
Climate normal for this date — 60-year average.
Average high76°
Average low52°
Average precipitation0.01 in
Chance of precipitation8%
Record high91° (1997)
Record low43° (2003)
Tue, 0376° / 51°0
76 °
Simi Valley, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high76°
Average low51°
Average precipitation0 in
Chance of precipitation8%
Record high91° (2018)
Record low39° (1994)
Wed, 0476° / 52°0.02
76 °
Simi Valley, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high76°
Average low52°
Average precipitation0.02 in
Chance of precipitation7%
Record high94° (2020)
Record low38° (1994)
Thu, 0574° / 51°0.01
74 °
Simi Valley, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high74°
Average low51°
Average precipitation0.01 in
Chance of precipitation3%
Record high92° (2020)
Record low39° (2011)
Fri, 0673° / 52°0.03
73 °
Simi Valley, Friday, 6 November
Climate normal for this date — 60-year average.
Average high73°
Average low52°
Average precipitation0.03 in
Chance of precipitation8%
Record high89° (2006)
Record low44° (1973)
Sat, 0772° / 52°0.07
72 °
Simi Valley, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high72°
Average low52°
Average precipitation0.07 in
Chance of precipitation17%
Record high91° (2006)
Record low37° (2011)
Sun, 0872° / 51°0.08
72 °
Simi Valley, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high72°
Average low51°
Average precipitation0.08 in
Chance of precipitation17%
Record high89° (2025)
Record low40° (2011)
Mon, 0971° / 50°0.04
71 °
Simi Valley, Monday, 9 November
Climate normal for this date — 60-year average.
Average high71°
Average low50°
Average precipitation0.04 in
Chance of precipitation10%
Record high88° (2016)
Record low41° (2011)
Tue, 1071° / 50°0.03
71 °
Simi Valley, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high71°
Average low50°
Average precipitation0.03 in
Chance of precipitation12%
Record high90° (2025)
Record low40° (2000)
Wed, 1171° / 50°0.06
71 °
Simi Valley, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high71°
Average low50°
Average precipitation0.06 in
Chance of precipitation12%
Record high86° (2019)
Record low37° (2000)
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 Simi Valley, 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 Simi Valley, 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.