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Re: Help with reading a weather chart
RichH's comments are correct.
While your general observations on the chart are pretty right on, i'm pretty sure you are thinking in terms of surface based features. But since it is a 500mb chart you can't make too many inferences to the surface based weather on what you see here.
Highs and lows on this chart determine whether there is upper support or not for surface based weather systems. Surface based systems will typically move in the direction of the parallel isobars. That is why they call the 500 chart the driving chart, because it drives the surface based systems.
That upper low over ireland you mentioned is connected to a surface low and also has upper air support at the 250mb level. This is called a cold low, and tends to be associated with continued bad surface weather (ie. thunderstorms, heavy precip, high winds). the surface conditions on the western coast of ireland today are low stratus ceilings with rain and drizzle and winds gusting 25 kts from the south east. sig weather charts show layers of cloud to 24000 ft with embeded cb's to 32000. the thing is it's not always as easy to see significant surface weather by just looking at a 500 chart. there is a trough line depicted along the eastern seaboard of the US that would tend to support instability aloft giving rise to thunderstorms, yet if you look at the surface weather there today, virginia is really the only area encountering sig thunderstorms.
I might suggest that you start with surface charts, and learn cylogenesis theory first. once you have a full grasp of how systems develop, move and die along with the associated cloud types and weather, then you can start to think in terms of the air column and how the upper atmosphere contributes to the surface weather's evolution.
A meteorology instructor once told me to think of the atmoshere like a river with rapids in it. The eddies around rocks acting much the same as air around lows. it helped me try and visuallize the larger picture of why weather does what it does.