Weather

[celesteh89]

What is the relation between cold fronts, warm fronts, high pressure systems and low pressure systems?

It always make a knot in my brain when tying to corelate them.


Thanks

 

[James331]

Cold front and low pressure are typically not good.

 

[celesteh89]

Yes, that I know, but is what prssure system is associated with each of them?

 

[cgrab]

All fronts are associated with low pressure systems. All air moves to the right when flowing downhill (in the northern hemisphere). Think of a high as a hill. The air flows straight out from the center but then turns right-thus clockwise circulation. The same is true for a low which is a bowl, the air flows towards the center but turns right-thus a counterclockwise circulation. The fronts happen as the air piles up in the bowl coming from different areas of different temperatures.

 

[Rigged4Flight]

On a map, the wind blows to the left (counter-clockwise) and toward the center of low pressure systems. The wind in a high pressure system blows to the right (clockwise) and away from the center. Just like elevation lines on a topographic map, when the isobars on a weather map are close together, that indicates an abrupt change. Winds will be especially strong in those areas.

Falling barometric pressure means bad weather is coming. Rising pressure means good weather. You can generally expect to find rain at the center of a Low Pressure system. Usually, showers and thunderstorms ahead of the cold front are shorter in duration than the rain ahead of a warm front. Because of the counterclockwise rotation around low-pressure areas, cold air is more likely to be found to the north and west of low-pressure areas while warm air is often to the south and east of low-pressure areas.

When you hear a weather report referring to a trough or ridge, they are just talking about long areas of low pressure (troughs) and long areas of high pressure "ridges."

Weather advisories are issued when a significant weather event is in the forecast.
Weather watches are issued 12-48 hours before the significant weather event.
Weather warnings are issued when the significant weather event is taking place.

Any cloud type with a "nimbus" suffix means it's raining.
You cannot have a thunderstorm if there are no cumulus clouds.

When a local weather reporter says there is a 60% chance of rain, they are saying that it will rain over 60% of the viewing area. In other words, the chance of rain is 100% for 60% of the area.

edit: This graphic is full of neat info

 

[AggieMike88]

What is the relation between cold fronts, warm fronts, high pressure systems and low pressure systems?

It always make a knot in my brain when tying to corelate them.


Thanks

Perhaps this might help? (image is a link to the ASA site where you can find out more on this book)

 

[celesteh89]

Thanks, all very good answers. Helped me very much

 

[GeorgeC]

Try page 35 of Aviation Weather.