Weather balloon soundings
Twice a day, the National Weather Service sends up weather balloons from about 70 sites across the lower 48. Each one measures temperature, moisture and wind from the ground to about 100,000 ft. Meteorologists read these as charts; here each one comes with plain notes on what it means for work outside.
Pick the site nearest you, or tap any spot on the map for a forecast sounding.
Tap anywhere for a forecast sounding
Balloons only go up at about 70 places, twice a day. For any other spot and time, tap the map: you get the HRRR (next 2 days) or GFS (next 10 days) forecast model's sounding for that spot, with the same plain notes.
About soundings
Balloons go up at about 6 a.m. and 6 p.m. Central time (12Z and 00Z) and take about 2 hours to climb. The numbers show what the air was doing at launch, so they are a snapshot, not a forecast. Conditions change through the day, especially in the afternoon and when a front passes.
Wind at crane height is the measured wind about 260 ft (80 m) up. Storm fuel (CAPE) is how strongly a rising bubble of air would keep rising. Wind change with height (shear) helps storms last and turn severe. Water in the air (precipitable water) is how much rain the whole column would make if it all fell. Notes like these are a planning aid, not an official forecast or warning. For warnings, follow the National Weather Service.
Want this for a job? AtmosDays Plus and Pro show the HRRR model's hour-by-hour wind at crane height for each jobsite, for the next 2 days. See how it works.
Data: NOAA National Weather Service upper-air soundings, via Iowa State University's Iowa Environmental Mesonet. Explanations by AtmosDays.