Prognostic chart the correct location. By 1957, it was proposed when isobars or height lines at the pressure level in the atmosphere were being verified, that the degree of persistence should be considered so as to avoid getting bad forecasts for slow moving systems too much credit. Prognostic chart A prognostic chart is a map displaying the likely weather forecast for a future time. Such charts generated by atmospheric models as output from numerical weather prediction and contain a variety of information such as temperature, wind, precipitation and weather fronts. They can also indicate derived atmospheric fields such as vorticity, stability indices,
Dry line vicinity of the reversal aloft, severe weather is possible, especially when a triple point is formed with a cold front. The dry line is most common in the spring. Its location is close to the location of the isodrosotherm, or line of equal dewpoint. The location of the dryline may not be marked with a surface pressure trough or shift of the wind direction. It bulges more to the east underneath the location of the highest winds within the jet stream. While dry lines are most common in the Great Plains, northern India also witnesses a similar moisture boundary. In