Current Conditions

Rosemont, California

77°F25°C
Drizzle

Wind

SSW 8 mph13 km/h

Humidity

45%

Cloud Cover

83%

As of Wednesday, September 2, 2026 at 2:35 PM PDT

Today's Outlook

Day

Mostly cloudy and warm, with a high of 79°F26°C and morning low of 72°F22°C. Breezy from the SW at 7 to 8 mph11 to 13 km/h. 10% chance of drizzle.

Night

Partly cloudy, with a low around 67°F19°C. Light wind from the SW around 6 mph10 km/h.

7-Day Forecast

DayConditionHigh (°F)Low (°F)Precip (mm)Cloud Cover (%)Wind (mph)
DrizzleHigh 79°F26°CLow 67°F19°CPrecip 0 in0.1 mm10%Cloud 60%Wind SW 7 mph11 km/hWednesday: Mostly cloudy and warm, with a high of 79°F26°C and morning low of 72°F22°C. Breezy from the SW at 7 to 8 mph11 to 13 km/h. 10% chance of drizzle. Wednesday Night: Partly cloudy, with a low around 67°F19°C. Light wind from the SW around 6 mph10 km/h.
DrizzleHigh 77°F25°CLow 60°F16°CPrecip 0.02 in0.6 mm24%Cloud 58%Wind SSW 6 mph10 km/hThursday: Mostly cloudy and warm, with a high of 77°F25°C and morning low of 63°F17°C. Breezy from the SW at 7 to 9 mph12 to 15 km/h. 12% chance of drizzle in the afternoon. Thursday Night: Mostly cloudy, with a low around 60°F16°C. Breezy from the SSW at 5 to 7 mph9 to 11 km/h. 24% chance of drizzle in the evening.
DrizzleHigh 78°F26°CLow 62°F17°CPrecip 0.02 in0.4 mm22%Cloud 41%Wind SSW 5 mph8 km/hFriday: Partly cloudy and warm, with a high of 78°F26°C and morning low of 63°F17°C. Light wind from the SSW around 5 mph8 km/h. 10% chance of drizzle. Dry air. Friday Night: Partly cloudy, with a low around 62°F17°C. Light wind from the SSW around 5 mph8 km/h. 22% chance of drizzle overnight.
ClearHigh 82°F28°CLow 57°F14°CPrecip 0 in0 mmCloud 17%Wind SW 4 mph7 km/hSaturday: Mostly clear and warm, with a high of 82°F28°C and morning low of 61°F16°C. Light wind from the SW around 4 mph6 km/h. Saturday Night: Mostly clear, with a low around 57°F14°C. Light wind from the SSW around 4 mph7 km/h.
ClearHigh 81°F27°CLow 59°F15°CPrecip 0 in0 mmCloud 12%Wind SSW 6 mph10 km/hSunday: Mostly clear and warm, with a high of 81°F27°C and morning low of 61°F16°C. Breezy from the SSW at 7 to 8 mph12 to 13 km/h. Dry air. Sunday Night: Mostly clear, with a low around 59°F15°C. Breezy from the SSW at 5 to 7 mph9 to 11 km/h.
ClearHigh 85°F29°CLow 57°F14°CPrecip 0 in0 mmCloud 7%Wind NW 4 mph7 km/hMonday: Mostly clear and warm, with a high of 85°F29°C and morning low of 61°F16°C. Light wind from the NW around 5 mph8 km/h. Dry air. Monday Night: Mostly clear, with a low around 57°F14°C. Light wind from the NW around 4 mph6 km/h.
ClearHigh 88°F31°CLow 59°F15°CPrecip 0 in0 mmCloud 36%Wind W 3 mph6 km/hTuesday: Partly cloudy and hot, with a high of 88°F31°C and morning low of 62°F16°C. Light wind from the W around 3 mph5 km/h. Dry air. Tuesday Night: Partly cloudy, with a low around 59°F15°C. Light wind from the WSW around 4 mph6 km/h.

15-Day Forecast

Day High Low Precip Cloud Cover Condition Wind
WednesdaySep 279°F26°C67°F19°C0 in0.1 mm· 10%60%DrizzleSW 7 mph11 km/h
ThursdaySep 377°F25°C60°F16°C0.02 in0.6 mm· 24%58%DrizzleSSW 6 mph10 km/h
FridaySep 478°F26°C62°F17°C0.02 in0.4 mm· 22%41%DrizzleSSW 5 mph8 km/h
SaturdaySep 582°F28°C57°F14°C0 in0 mm· —17%ClearSW 4 mph7 km/h
SundaySep 681°F27°C59°F15°C0 in0 mm· —12%ClearSSW 6 mph10 km/h
MondaySep 785°F29°C57°F14°C0 in0 mm· —7%ClearNW 4 mph7 km/h
TuesdaySep 888°F31°C59°F15°C0 in0 mm· —36%ClearW 3 mph6 km/h
WednesdaySep 988°F31°C62°F17°C0 in0.1 mm· 3%31%ClearWSW 4 mph7 km/h
ThursdaySep 1089°F32°C63°F17°C0.02 in0.4 mm· 3%23%ClearSW 5 mph7 km/h
FridaySep 1187°F31°C63°F17°C0.03 in0.7 mm· 4%21%ClearSSW 5 mph8 km/h
SaturdaySep 1285°F29°C62°F16°C0.02 in0.5 mm· 7%27%ClearSSW 5 mph8 km/h
SundaySep 1385°F29°C61°F16°C0.05 in1.2 mm· 7%22%ClearSW 5 mph8 km/h
MondaySep 1487°F30°C61°F16°C0.02 in0.4 mm· 3%15%ClearWSW 4 mph7 km/h
TuesdaySep 1589°F32°C61°F16°C0.01 in0.3 mm· 3%14%ClearSW 4 mph7 km/h
WednesdaySep 1689°F32°C62°F17°C0.01 in0.2 mm· 3%17%ClearSW 4 mph7 km/h

Nearby Cities

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 38.5519°N, 121.3647°W·Elevation: 15m·Timezone: America/Los_Angeles·Population: 22,681