March 9, 2026 7:55 PM

Hot and Sticky Weather for the First Week of September

SOUTHERN CALIFORNIA, CA. (Pain In The Pass) >> This week’s weather forecast for Monday September 1 through Friday September 5 for Southern California. Check out the 5-day forecast below in your area.

Cajon Pass/Inland Empire Valley Area Average Weather/Temps:

Monday will be hot, mostly sunny, and a high of 102°. Tuesday will be hot, mostly sunny with a chance of rain showers and thunderstorms, with a high of 101°. Wednesday will be hot, mostly sunny, and a high of 100°. Thursday will be hot, sunny, and a high of 98°. Friday will be hot, mostly sunny and a high of 96°.

High Deserts Area Average Weather/Temps:

Monday will be hot, sunny, windy, and a high of 102+°. Tuesday will be hot, mostly sunny with a chance of rain showers and thunderstorms, windy, and a high of 101+°. Wednesday will be hot, mostly sunny with a chance of thunderstorms, windy and a high of 100+°. Thursday will be hot, mostly sunny with a chance of thunderstorms, windy, and a high of 98+°. Friday will be hot, mostly sunny with a chance of thunderstorms, windy, and a high 96+°. Higher temps in the Barstow area.

Mountains Area Average Weather/Temps:

Monday will be warm, sunny, windy, and a high of 80°. Tuesday will be warm, mostly sunny with a chance of rain showers and thunderstorms, windy, and a high of 78°. Wednesday will be warm, mostly sunny with chance of and thunderstorms, windy and a high of 76°. Thursday will be warm, mostly sunny with a chance of thunderstorms, windy, and a high of 74°. Friday will be warm, mostly sunny with a chance of thunderstorms, windy, and a high of 73°.

*Timing of the Weather on each day can change.

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Cajon Pass
7:55 pm, Mar 9, 2026
temperature icon 56°F
clear sky
Humidity: 45 %
Pressure: 1012 mb
Wind: 13 mph
Wind Gust: 10 mph
Clouds: 0%
Visibility: 10 km
Sunrise: 7:08 am
Sunset: 6:52 pm
  • Temperature
  • Precipitation
  • Rain Chance
  • Wind
  • Humidity
  • Pressure
8:00 pm
temperature icon
48°/56°°F 0 mm 0% 6 mph 45% 1012 mb 0 mm/h
11:00 pm
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40°/51°°F 0 mm 0% 6 mph 55% 1013 mb 0 mm/h
2:00 am
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36°/43°°F 0 mm 0% 4 mph 66% 1013 mb 0 mm/h
5:00 am
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35°/35°°F 0 mm 0% 5 mph 79% 1014 mb 0 mm/h
8:00 am
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38°/38°°F 0 mm 0% 6 mph 78% 1016 mb 0 mm/h
11:00 am
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59°/59°°F 0 mm 0% 5 mph 47% 1017 mb 0 mm/h
2:00 pm
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64°/64°°F 0 mm 0% 8 mph 40% 1015 mb 0 mm/h
5:00 pm
temperature icon
63°/63°°F 0 mm 0% 7 mph 43% 1016 mb 0 mm/h