Hi,Using AS1.7 and when out of range of a valid WMO ALOFT station, what logic goes into the upper level winds simulation? Does the program simply reference surface winds or does it take into account actual ALOFT data from the nearest out of range stations in order to build a simulated upper level wind model with fidelity? Thank you.

Hi there,Actual winds station data is not used at all during simulation. The fidelity is limited but is based on computations that take the surface wind and pressure, distance from the equator and pressure altitude, and slight randomization into account to come up with the upper wind values. These are processed ON THE FLY each time you change altitude of more than 3000ft.Using long-distance stations to fill in and interpolate was attempted but the results were not as accurate as we'd hoped. I will look into this in the future for the private wx server solution. My hope is to poplate EVERY METAR station with upper wind info as well - this will all be formulated with a new wind model based on the world-wide winds reports as they are available. Sort of a cross of what we have now and what you suggested. Hope that helps!-Damian[table border=0" cellspacing="30" cellpadding="0][tr][td align = "left"]Damian ClarkHiFi Simulation SoftwareDeveloper of ActiveSkyThe next-generation weather environment simulation for FS2002!http://hifi.avsim.net/activesky[/td][td]http://hifi.avsim.net/activesky/images/wxrebeta.jpg][/td][/tr][/table://http://hifi.avsim.net/activesky/ima...][/tr][/table

Ok, thanks.