Rancho Cucamonga, California weather

Local weather, a 7-day forecast and tonight's sky for Rancho Cucamonga, California.

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Live radar and clouds

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Hourly forecast

Next 24 hours. Scroll sideways for later hours.

Daily forecast

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Weather details

Current conditions

Sun & moon

Times in the place's local time

About NalssiSky

Local weather, tonight’s sky and ISS passes for a searched place. Full data sources and credits are listed further down this page.

Scene pictures are illustrations, not photographs of current conditions.

Alerts for U.S. places are checked about every 2 minutes while this page is open and visible. This page can be several minutes behind official alerts.

This site’s technology is maintained by EVULNABLE.

Pollen forecasts for U.S. places, where shown, include Google Maps content. Its use is subject to the then-current Google Maps End User Additional Terms of Service and the Google Privacy Policy.

DATA SOURCES

Sources used on this page

What each source provides.

WEATHER & FORECAST

WeatherAPI + Open-Meteo

WeatherAPI.com: current conditions, U.S. hourly forecasts, sun and moon data, and air quality. Open-Meteo: place search (GeoNames data), and hourly and daily forecasts outside the U.S. WeatherAPI.com place search is used only if the Open-Meteo geocoder fails.

U.S. FORECASTS

National Weather Service

Daily forecasts and alerts for U.S. locations.

EUROPEAN WARNINGS

EUMETNET – MeteoAlarm

Official weather warnings from participating National Meteorological and Hydrological Services, for European locations. Warning areas: EUMETNET – MeteoAlarm geocodes (2026-07-31), converted to a grid on this site.

SKY IMAGERY

NASA

EPIC Earth images, and planet and sky images from the NASA image library.

PLANET POSITIONS

JPL Horizons

Planet azimuth, elevation and magnitude for the searched place.

TONIGHT'S SKY

AstronomyAPI

Moon constellation and planets above the horizon at 9 PM local time.

SATELLITE PASSES

N2YO.com

Predicted ISS visible passes for the searched place.

NOTE

Not an emergency service

Coverage and update times vary by place. For hazardous weather, use your local official weather service.

Full data sources

U.S. daily forecasts and alerts: National Weather Service (weather.gov). NWS does not endorse this site.
Rain levels: Environment and Climate Change Canada, Manual of Surface Weather Observation Standards (MANOBS), 8th edition, amendment 2, February 2023. The light, moderate and heavy rain numbers are its rain-rate classes.
Tile words and bars: the pressure change words (steady, slowly, quickly) are the Met Office 3-hour pressure tendency classes. The visibility words use the 1, 3 and 5 mile edges of the U.S. flight categories as a convention, not an official scale. The PM2.5 and PM10 bars use the U.S. EPA 24-hour breakpoints (Technical Assistance Document for the Reporting of Daily Air Quality, EPA-403/B-26-003), applied to the hourly model value for scale only; that is not an air quality index.
U.S. pollen forecast: Google Pollen API. Its source line, terms and privacy links are shown with the pollen data.
Images: NASA (EPIC). NASA does not endorse this site.
Planet positions: NASA/JPL Horizons System
Sky data: AstronomyAPI.com
Satellite data: N2YO.com. Source data: Space-Track (U.S. Space Force); not an endorsement by that agency.
Place search: Open-Meteo geocoding, location data based on GeoNames (CC BY 4.0). WeatherAPI.com search is used only if the geocoder fails.
Weather detail tile pictures: AI-generated with ChatGPT (OpenAI).

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