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How does nowcasting predict weather several hours ahead?

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Weather forecasting Doppler radars, such as this one operated by the U.S. National Weather Service at New Underwood, South Dakota, extract the Doppler frequency shift of the echo produced by a moving target by noting how much the frequency of the received signal differs from the frequency of the signal that was transmitted.

Nowcasting is a specialized method of weather forecasting designed to predict local atmospheric conditions several hours in advance. Unlike broader numerical models that simulate large-scale atmospheric physics, nowcasting relies on the rapid processing and display of real-time data from radar and satellite observations.12

By utilizing these high-resolution, local measurements, meteorologists can track the immediate development and movement of weather phenomena, such as thunderstorms. This approach allows for precise, short-term projections that improve upon the limitations of traditional, large-scale numerical models. Specialized facilities, such as the National Oceanic and Atmospheric Administration's PROFS (Program for Regional Observing and Forecasting Services), are equipped to handle this rapid data integration to provide timely updates on changing local conditions.12