Since I acquired my ABC watch about a month ago, my interest in using a barometer to forecast weather has been renewed. I wanted to get your thoughts on rules of thumb you use when you use your barometer/watch to try to forecast the weather. I read a post from Queen6 back in February where he said that observation of barometric trends was VERY useful when he predicted the weather while on a somewhat hazardous trip he had to make, so his comments would be particularly welcomed.
I know that dropping pressure can signal bad weather approaching, and rising pressure can signal improving weather, but so far, my forecasts have not been particularly accurate.
My questions run like this:
--How much of a drop constitutes a "large" drop in pressure?
--What do you determine is a high and low pressure, particularly when you use that pressure to mark the start of a trend (up or down)?
--How quickly would pressure need to rise (or drop) to indicate a weather change?
I'm looking for general rules of thumb you apply when you try to predict the weather using just your watch, when you have no other information available when you are out in the field. Perhaps you also have ways of factoring in cloud observations, temperature, and humidity? I realize there are no magic answers here, but personal experiences from others could be beneficial as I gather my own opinions about how pressure changes can be used to predict weather.
By the way...to provide some context, I live near sea level, just south of Washington, DC, about 125 miles west of the Atlantic coast. Pressure has varied between between 29.65 and 30.20 in Hg since I received the watch on May 2. We've had no big storms during this first month with the watch.