National Weather Service United States Department of Commerce

Back-to-Back Winter Storms Across the North-Central U.S.; Severe Weather Threat in the Midwest

A late-season winter storm continues to bring heavy snow, significant sleet, and disruptive icing to the Upper Midwest and western Great Lakes into the morning; and will be followed by another storm. Severe thunderstorms continue across the Midwest to the lower Great Lakes through tonight, before bringing a round of freezing rain and sleet Friday morning across northern New England. Read More >

Upper Air Observations


Decoded Upper Level Winds

Plotted Upper Air Soundings

GOES Derived Atmospheric Vertical Soundings

Alternate Sources for Upper Air Soundings
Ohio State

California Wind Profiler Data Can be Found Here

Why Do Forecasters Still Rely on Weather Balloons?

Twice every day, from nearly 100 locations in the United States, the National Weather Service launches weather balloons, carrying instrument packages called radiosondes. Radiosonde sensors measure upper-air conditions such as atmospheric pressure, temperature and humidity, wind speed and direction. The data is important for aviation safety, and meteorologists use radiosonde information to prepare weather forecasts.