a few more clues from nature

1. swallows flying low may indicate the air pressure is dropping.

2. static electricity may increase the grooming activities of cats.

3. the calls of some birds, including crows and geese, have been known to be more frequent with falling pressure.

4. deer sometimes react to wind and air pressure by coming down from mountains and seeking shelter.

5. some species from rabbits to rattlesnakes to certain kinds of fish may feed more before a storm so they can seek shelter.
6. some flowers close up as the humidity rises so rain doesn't wash away their pollen.

7. the leaves of some trees curl just before a storm.

8. the higher the humidity, the better sound travels. some english people gauged the chances of rain by the clarity with which they heard church bells sound. (i have to disagree with this one... ever tried to yell at someone in humid NC? you can't hear it nearly as well as if you were in arid NM. and the trees don't make a difference... because where i was in NM was both wooded AND hilly, unlike the flat, open soybean fields in NC where you can't hear from one row to the next...)

9. drop in barometric pressure often affects people with joint diseases, bad teeth, recently healed broken bones, or corns and bunions, bringing pain or pressure to those areas of the body.

10. cicadas can't vibrate their wings when the humidity is very high, so may be silent when rain is approaching. Flying insects are more active when the air pressure drops and stay closer to the ground, so they seem to be swarming before a rain storm.

11. the chirping of a cricket has been shown to provide a close indication of air temperature. By counting the number of cricket chirps in a 14-second period and adding 40, the total will equal the air temperature to within one degree 75% of the time.

12. after the barometric pressure dropped just a few millibars -- an occurrence that causes a similar change in hydrostatic pressure -- sharks swim to deeper waters, where there is more protection from the storm.

13. seagulls are sensitive to barometric changes. it's thought that they return to land if they feel pressure drop.