Weather test, storms are on the way

 So there are some fall storms headed our way according to weather forecasts, one on Saturday has potential for being nasty.
I've have the below barometer for few years sitting on a shelf, no sure if it works or not, so I'm conducting an experiment.
I looked up the above chart, to know how to read the thing..although it has handy dandy labels on the front saying fair to stormy.

 Here''s what it reads Wednesday morning..29.9 ..with a corresponding picture of the weather in the backyard.
Taken about same time. Right now it's holding steady/appears to be accurate.

 Here it is again with the brass needle set to our start point..so we can see change over time.