Re: Which of the two variables has more affect on local weather?

There is no hard and fast rule for which is more dominant feature affecting 
weather on a daily basis.  Fronts are boundaries marking the transition 
zone between air masses.  If the air masses have vastly different 
characteristics (temperature and moisture content), then the boundary 
between them is very distinct.  If the air masses are fairly similar, then 
the front marking the boundary between them can be very indistinct.  

Typically, an area of low pressure has a warm front emanating from the 
center of the low toward the east and a cold front emanating from its 
center toward the south or southwest.  Well behind (west of) the cold front 
will be a high pressure center while another area of high pressure will be 
well ahead (east of) the area of low pressure.

However, as boundaries between differing air masses fronts can form without 
accompanying areas of low pressure.  Sometimes, southerly flow on the west 
side of an area of high pressure will result in the formation of a warm 
front.  Other times, north to northwest winds east of an area of high 
pressure will result in cold frontal formation.

The processes involved in frontal and cyclone formation are extremely 
complicated.  Good summary information can be found in many different books 
written for the layman.  Your local bookstore or library should have 
several.  Some examples include: The Weather Book (by Jack Williams of USA 
Today), The National Audubon Society Field Guide to North American Weather, 
Weather (A Golden Guide), and A Field Guide to the Atmosphere (Peterson 
Field Guide).