My Husband's son is really interested about meteorology where can I purchase those instruments of precision (like for example a barometer ), also are they any association or meeting where he can participate either e-mail or... anything will help thank you

I don't know how feasible this is but perhaps you can look for a planetarium or a science museum near you? If that doesn't pan out, look for a science store or educational toys store. Or write into the local TV news channel to ask their weather folks what might be available in your area? There might be a possibility of him becoming a local "weather watcher" for them -- I know our TV news channels do that here. Just a few thoughts off the top of my head that I hope are helpful.

Thank you for posting your question to the Ask Me Help Desk.

Here are some websites that you can browse for some precision weather stations.

Weather Shack
Columbia Weather Systems
Weather Patrol
Warren Weather Equipment
Ambient Weather
Weather Underground

There are also several units to choose from at places like Wal-Mart but functionality will be limited.