Upper Air Observations

Late Wet Seasons

Pattern change

With no precipitation expected through at least Tuesday, November 19th, 2019, this will be one of the top three latest starts to the wet season in Central California. Precipitation records at Fresno date back to 1881. Precipitation records at Bakersfield date back to 1893.

A significant change in the overall pattern is possible next week. If so, it would be a welcome change with with the possibility of wet weather by November 20th. Details are not certain at this point, but it is the best chance in a very long time that much of central and southern California will receive precipitation. Stay tuned to the latest NWS forecasts for updates on this evolving pattern.

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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.