Today I saw -4C at FL170.
A few years ago I saw -37C at FL190.
Almost the same time of the year.
I take it as you could not fly FL190 today
My personal record is -46C at 4000 feet in a 172 (central Quebec), and +44C landing a Twin Otter at Cairo.
I should have said “aloft”
Also the two extremes were with a similar surface temperature.
I have recorded 0 at FL180 and -32 at FL180 but definitely not same time of the year.
I am convinced the air at higher GA altitudes is getting warmer.
Maybe not at FL400 where things are much more uniform, because the temperature is more closely tracking the pressure. But at “GA IFR” levels I have never seen such warm air as I have seen in the last 5-10 years.
I agree with @ Peter, coming back from Corsica at the end of June last year itmwas +17 at FL 100
I know it is a different ballgame (B747-8F), but in Novosibirsk two years ago, on the ground, I had -38 C with QNH 1053. At the cruising level FL330 I got -76 C and shortly after I got the FUEL TEMP warning, because it dropped below -45C
2-3 weeks ago, when it was told, that Syberia has extrem warm, I had -20 C on FL350 as SAT the TAT was around +5. I had to switch on ENG Anti. Ice which is very rare to get ICE at this altitude.
I recall from AF447 that somebody said a jet cannot fly (at all) at FL350 in -20C SAT … Clearly they were wrong And -76C is getting close to the BA038 scenario, which I believe was -82C or so and was encountered by 0.1% of all flights.
It is interesting that you get these crazy temps high up too.
Highest I ever had was in Seville / LEZL some years ago. When filing my flight plan the met guy said ‘have a look’ and pointed to a screen showing the temperature right above the runway – it was 52C. OAT was something like 47C, of course measured by the usual device in it’s nice shady box.