IEM Daily Feature
Wednesday, 09 February 2011

All about pressure

Posted: 09 Feb 2011 03:33 AM

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yearly ties are all included
Very cold air has settled into the state thanks to a robust area of high pressure. The altimeter reading (a measure of pressure) yesterday morning was a few hundredths of an inch below the highest value reported so far this year. The featured chart presents the yearly events of when the highest and lowest altimeter readings were observed. The first chart compares the air temperature against the day of the year for the observation. The highest pressure events are associated with colder temperatures than low pressure events as confirmed by the second chart. Low pressure events tend to be with dynamic storm systems (upward motion) that are windier than high pressure events (downward motion). The last chart shows the time of day that each event type occurs. High pressure events mostly occur during the morning hours when the atmosphere is still cooling, while low pressure events happen about any time of day.

Good = 22
Bad = 6

Tags:   climate   pressure