GFS Forecast Model: 500mb Heights - Real-time

Meteorologists often look to the "middle" of the atmosphere—roughly 18,000 feet (5,500 meters) above our heads—to understand the primary drivers of global weather. This dataset visualizes the 500mb constant pressure surface. Instead of looking at a fixed altitude, we are looking at the varying height where the atmospheric pressure reaches 500 millibars.

On the sphere, the atmosphere is depicted as an undulating surface of peaks and valleys:

• High Heights (Warmth/Red): Where the air is warm and expanded, the 500mb level is pushed higher. These "ridges" act like a dome, typically bringing clear skies and stable, warm weather to the surface.
• Low Heights (Cold/Blue): Where the air is cold and dense, the 500mb level sits closer to the ground. These "troughs" are like valleys where air moves toward the center of the low and creates the best conditions for rain, snow, and wind.

The animations shown here are generated by the Global Forecast System (GFS), a sophisticated numerical weather mode developed by NOAAl. By feeding current global observations—from satellites, weather balloons, and ground stations—into complex mathematical equations, the GFS simulates how these ridges and troughs will migrate around the planet over the next 180 hours from the model run.

GFS 500 mb geopotential height fields are taken from GRIB2 output of NOAA's Global Forecast System, obtained through NCEP NOMADS. The animation shows global height values as the shaded map with height contours at the same level. The visualization is updated once per day and shows a 180-hour forecast sequence. Python was used to process and visualize these fields.

• Time frame: Real-time, updated once per day
• Frequency: 1 frame every hour
• Range: 180 hours (7.5 days)
• Variable: 500 mb heights