24 hr National Jetstream Forecast @ the 12000 meter level in meters per second (m/s). 1 m/s = 3.6 kilometers per hour (km/h). This altitude is near the level of the core of the jet stream. So the tracks of the jet streams can be seen very clearly. The streamlines indicate the direction of flow of the wind. The color of the streamlines indicates a relative measure of divergence of the flow in the upper troposphere. Orange and red indicates strong divergence at upper levels, usually associated with strong vertical velocities in the middle troposphere, and severe weather/heavy rainfall.