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Hi,I have a couple of questions related to AS 2012 & PMDG 737 NGX.1) I plan a flight, for example, from EETN to LKPR (CRZ ALT F400). When I need to know what the CRZ TAS is going to be, I have to know the OAT in that level -- then I calculate speed mach 1 (in kts) according to that OAT and multiply it by the mach number which is going to be my CRZ (ECON from FMC); the speed that is economical for me in F400 is mach 0.782 … that's why I need accurate OAT -- BUT here I see the problem: For filling T/C OAT in FMC, I always find any airport that is located near by the T/C point (seen from NavDisplay), then I write this ARPT (ICAO) to the Active Sky (Wx Report) to see the TEMP at the required FL (under the symbols of weather, there are wind and temperature information for certain altitudes -- 3K, 6K, 9K, … 49K) -- so from that I can read that e.g. in 39K feet the OAT is –57.4 °C etc. According to that temps, I calculate the OAT for 40,000 ft (which is sometimes higher than in lower FLs -- possible?) -> I put that temp. to this http://www.csgnetwor...achonecalc.html and just calculate the mach 1 speed according to that temp, and then multply it by e.g. 0.782 -> I find out that my CRZ speed (that I also fill in the FPL) is going to be +- 447 KTAS. … well, as soon as I reached F400, I saw in FMC that the OAT was much lower, approximately –77 °C, so my airspeed then was a bit lower, e.g. just 425 KTAS and not 447 as I had been expecting… But if I check the weather at AS (locked to nearest ARPT), I can see there's just written something like 39K & –55.8, 44K & –57.4 --- so how is it possible that I have so much lower OAT than everywhere is issued? -- now I mean also this: http://jeppesen.com/...ion-weather.jsp -- also showing the TEMP if you open the wind forecast -- e.g. FL390 & showing –55 °C, but in FMC I can see OAT –77 °C…So, I'd like to know if the AS (and then aslo the JEPP. weather) shows the OAT correctly (-> then there must be any problem with FSX/PMDG), or if the OAT that shows FMC is correct. (But I suppose there shouldn't be any incorrect entry in the JEPP. weather maps.) :)And why do I need to know it?Well, just because I don't like when something is not working as it should / is not accurate, then also to fill the CORRECT CRZ airspeed to the FPL, and finally, when I calculate the EETs to FIRs, then it's not accurate (according to the planned TAS & actual TAS -- even if the wind is calm).P.S. I'm not using FSInn, but Squawkbox with Weather settings OFF.And the second, last, not so long question: :)2) Is it very important to have very quick internet connection to get the actual METARs on time (with minimum delay)? Because I have Wifi connection and sometimes it's delayed up to 20 min. -- it's 10:20 Z and I still have valid METAR from 09:30 Z (instead of 10:00 Z). And just one more note: In AS 2012 settings, I have set Automatic Downloads (+ VATSIM Online Weather) to every 5 min., but if I look on Wx Report, I can see “Last Updated: 00:15” and now it's 00:43 -> so “Last Updated” should now be showing +- 00:40 (update every 5 mins.); am I correct? (if yes, why is it not?)Thank you very much in advance!Adam