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Guest hellogoodbye

Forecast questions

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(I though I already posted this question, but I can't find it anymore.. Maybe because I forgot to end with my real name... Sorry! I still have to get used to that...!)From the manual:ISA DEV/QNH: Destination airport temperature deviation from Standard Atmospheric Conditions and airport QNH. This information is used to plan the descent portion that will take place below the Transition Level entered at the 1L LSK.Question: here do I get the temp deviation information from...?From the manual:WIND ALT/ DIR/SPD:Wind altitude speed and direction entries are made by the crew based upon reported conditions, observed conditions (use the wind indication on the Nav Display!) or forecast conditions in order to assist the FMC in computing the descent profile as defined in the flight plan.Question: I know I can see the CURRENT wind/dir on the ND (although not always.......), but where can I get info about the weather further away...? This info is important to make good descents, so... I need to know the alt, dir and strength, but I can't find it anywhere...Jeroen van Engelen (Yo! I didn't forget my name this time! :)

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Hi Jeroen,1- you can find a nice table with all data pertinent to the ISA at:http://www.ae.su.oz.au/aero/atmos/atmtab.html 2- if you are using a meteo add-on such as AS2004 you can get the winds in the navlog, if not, better to download a couple of upper wind charts that give you winds forecast at fixed pressure levels in a graphical way (try browsing at: http://weather.noaa.gov/fax/). Or, as a last resort (that could be seriously wrong if your flight is a little longer than local), you can take note of the winds as your climbing as displayed on the ND and then put them into the FMC (quite an imprecise method if your are flying 2-3 hrs !).Hope this helps.

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Thanks for the info (you're a busy man on this forum! :)I have to dive a bit into the links you gave me (don't know yet if I will really grasp it all and can bring it to good use) but at least I know I'm not missing something: some hidden option or something like that! :)

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Jeroen,hope this helps:goto http://weather.noaa.gov/fax/otherfax.shtmlYou'll see a list of many weather charts.You can download, for example, the upper wind and temperature chart for the 18hr forecast Europe and North Atlantic at FL390.You'll find a chart with many "arrows": they show the direction from which wind is forecast to blow at FL390 in every location. You'll also see many numbers: thery're the forecast temperatures (always negative at that altitude).The "feathers" in the back denotes wind strenght (small short lines=5 kts; long lines=10 kts, triangles=50 kts).So you can approximate the wind direction and velocity at any point and put it in your fmc. If you get more charts, you'll get more levels.There are also other chart types, such as SIGWX, that depicts significant weather and the "jetstreams" (powerful west to east winds at high altutudes).Hope this can help you.As for the "busy man", I'll be on vacation next week...Cheers !

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