Brian Ellis <[log in to unmask]> wrote: I have discovered that there is a real limit to the conditions of natural temperature and humidity that are possible. To put it simply, if the temperature and humidity are high at ground level, clouds will form at a given altitude, reflecting solar radiation. This will result in a lowering of the temperature. I haven't yet determined the exact limit conditions, but it would seem that (very roughly), you can obtain 100% RH only if the temperature is under about 15°C. At 25°C, the max humidity is ~85%. At 35°C, 75%. At 50°C, 55%. ++++++++++ I have seen several days of temperature in the 90-100 F range and humidity of 95% and higher, particularly in Texas and Louisiana. I do not know where the limit is, but I have seen reported humidity by local weather of 102%. Jon Moore --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------