I’m curious about what people use to find out about the cloud tops before filing IFR.
There’s been some discussion around it on the forum, but check out Peters website if you haven’t done so already – http://peter2000.co.uk/aviation/ir-sat/index.html
Nothing! The really nasty stuff reaches high enough that only Concorde could fly above it and all the other clouds are there so that you did not spend your money for the instrument rating for nothing 
I would not say “nothing” because if you find yourself in IMC, anywhere between 0C and say -10C, it is only a matter of time before you get the white (or not so white, and maybe not smooth either) stuff collecting. I got some nice pics on the way back from LDLO 
In the non deiced world, you have to avoid extended-period IMC exposure in that temperature range – or have a really realistic escape route in the form of a descent into warmer air (above the MSA ) and preferably without declaring a mayday. Or have a motor which is big enough to allow you to say “sod this” and climb out of it – turboprop or jet, usually.
I have a couple of writeups on my website (linked above) but in short:
There is no even remotely accurate way to forecast cloud tops, beyond what can be guessed by looking at the MSLP chart (with a bit of experience).
There is no accurate way to get actual cloud tops (the data does exist in practically real time but EUMETSAT make €€€€€ out of it so you can’t get it directly – the typical €uropean “use taxpayer money to get it and then sell it” scam) but you can get a good enough idea from the IR images to see if they lie say FL100-150 or FL150-200 or FL200-300, so in the context of a high performance IR aircraft this is good enough. Sometimes this can be misleading however in the “false warning” sense e.g. a high level layer of haze, or just a thin cloud through which you can see the sun above you, and these just need to be judged on the actual flight and you climb up high enough to get the OAT below -15C or so. The main IR site is SAT24 (updated every 15 mins) and as a backup you get the same image updated every hour from the UK Met office
In the non deiced world, you have to avoid extended-period IMC exposure in that temperature range…
Yes, but during the time of year when it matters most, October to March more or less, there are usually no distinctive cloud tops, but a layered system of clouds that reaches from ground level to FL 200 – 300. Unless you are allowed to change your altitude frequently to stay between layers, you will fly inside cloud for quite some time.
That is not my experience so perhaps that is true if you fly through frontal weather, which I almost never do (overfly it, if possible, yes).
People who fly through fronts do report that they encounter layers, but to me that sounds like “do you feel lucky”. Also I think layers are mostly in cold fronts (outside of convective wx) while warm fronts tend to be solid IMC to maybe FL250.
But then the whole debate of attitude to this is a wide ranging one, with many attitudes to risk, and these are modulated by whether one is de-iced, etc.
Well, you guys now make this nice vertical profile of the enroute weather based on the GFS-model data. Combine this with IR cloud top temperature charts to verify if the model is OK or not. Then, get a Skew-T Log-P diagram of some points along the way (based on GFS data if balloon data is not available), so you can estimate if there are more likely going to be layers to the top of clouds or if it is going to be solid. The information combined with good experience will give you an estimate of where to expect the top of clouds. It is not always going to work out, so have a contingency plan ready. If in doubt, ask the controller if he can ask a departing jet or airliner aircraft to inform him of the top of clouds for you or in some cases they themselves (the controllers) have the information available already.
As for frontal weather flying, it is not something you have to avoid. The gradation of fronts is not always the same. There is a good video on flying in frontal weather from Sportys. See here: https://www.sportys.com/Pilotshop/product/13606
I think the frontal weather issue depends on what you were taught when you trained for your IR and is a personal issue.
I think the frontal weather issue depends on what you were taught when you trained for your IR and is a personal issue.
Aeroplus – your aircraft has
Confirm?
Peter: that is almost right (25000ft ceiling). However, I also flew through fronts in a Piper Archer II before flying the Cirrus. No deicing, ceiling theoretically of 15000ft and no sat weather. One front is not the other. And … depending on the temps, MSA amongst others, there might be a good way out in case.
I have been flying today, in England, and this morning the cloud topped out at 35600 feet. Not layers, solid cloud all the way. That’s rare.
