The National Weather Service is a component of the National Oceanic and Atmospheric Administration (NOAA). NOAA is an Operating Unit of the U.S. Department of Commerce.
Provide weather, water, and climate data, forecasts and warnings for the protection of life and property and enhancement of the national economy.
Everything about current and past weather can be found here. Forecast, maps, active alerts, news, education, weather safety, and more. This is a good link to have.