What are the pros/cons of using 850/500 hpa charts

[msx999]

As title - thanks a lot!

[k19]

850's are useful because the temperature here (about 1500m ASL) is not affected directly by solar factors, i.e they don't fluctuate by day/night time. One main use on these forums is that they are useful for forecasting when snow will fall as opposed to rain (850's of around -5 are needed for snow, although that is a vast simplification and other factors can effect the ppn type). They can also help with forecasting [very] approximate temperatures at ground level as they are indicative of the kind of air mass we are underneath (warm, mild etc).

I wouldn't be able to provide any in depth description of 500Hpa charts, apart from that they are useful for understanding what pressure systems and kind of weather associated with them is occurring. For example there may be high pressure at sea level around greenland on a normal slp map, however this could easily be a surface high (caused by the cold air), a 500Hpa chart shows when this is the case and when a true high pressure system exists by showing the air temperature at 500HPA using colours.

[msx999]

Thank you

So 850 is used predominantly to estimate temperatures and to forecast snow and 500s are to get a general overview of the pressure systems.

That is useful - I just wanted to know why posters in the model thread would post one rather than the other...