This post covers what you have heard TV Meteorologists call "Upper Level Disturbances". These mysterious entities go by other names like "short wave", an "impulse", a "velocity maximum" or a "jet streak". I like to call them "bundles of energy" because the energy part of the name tells the viewer that these jet stream-level disturbances energize the low pressure systems you see on weather maps at the surface along with their companion cold fronts and warm fronts.
It is within the bundles of energy that the highest jet stream wind speeds are observed, thus one of the names, "velocity maximum". So you have a jet stream and these bundles of energy follow the jet. What makes the forecast sometimes difficult is that the upper disturbances also can modify the jet if they are strong enough.
To be sure there is no confusion the upper level disturbances do NOT power tropical systems. In the tropics storms are driven by the energy released when water vapor (humidity) condenses back to liquid.
The way these bundles of energy work is beyond the scope of this post but with each one comes some lift and the chance for precipitation is there is sufficient moisture. This week moisture is scarce so precipitation will be light or non-existent.
The video describes how this week looks.
0 comments:
Post a Comment