[Rhodes22-list] Weather Forecasting

[Richard Smith]

If you stand with your back to the wind low pressure will lie to your left.

In a similar fashion high pressure will lie to your right.

Why this is so can be easily visualized.  In the northern hemisphere
circulation around an area of low pressure is always counter clockwise.
Therefore if you face away from the prevailing wind the center of a nearby
area of low pressure will always lie to your left.   Sketch it out...

For this phenomena to be true one must be within the circulation associated
with the depression.  That's what barometers are for!  If the pressure is
falling you are in a cyclonic circulation. A rising barometer implies the
approach of a high pressure system (anti-cyclonic)

Now what does this have to do with weather forecasting;  Severe weather is
always associated with low pressure because a low pressure (cyclonic)
circulation also features vertical (rising motions).  These rising motions
are responsible for cloudiness and precipitation.. bad weather.

High pressure (anti-cyclonic) circulation features descending  motions and
is associated with clear weather.

It follows then that by knowing the location of the storms center the
prudent mariner can take steps to avoid it.

What I have written here is greatly simplified but I think it gets the
concept across.

Richard Smith