Peter wrote:
GFS limits cloud data to three layers (low medium and high)
There’s an additional layer for convective clouds…
Peter wrote:
GFS is improving but this doesn’t appear to be feeding through to end products
Why do you think so? But quite frankly, a doubling of the resolution is not something to easily notice…
Another issue is that the GFS download server is severely bandwidth constrained…
I think that because the forecasts of where the clouds sit are still often fiction.
Sometimes the forecast is bang on and then everybody is happy 
I do think the data is way better than nothing for “high altitude IFR” (say FL100-200) but I don’t think that the cloud tops accuracy is better than say +/- 5000ft, and low level cloud (say below 10000ft) is completely missing most of the time.
Do you think the doubled resolution brings a higher accuracy? I thought the principal bottleneck in all these models is the lack of real time input data.
Do you guys have pireps that you report to FSS in real time? Its a really valuable tool for wx briefing and decision making. Too bad the airlines are above doing reports. As they used to do when they were still using avgas.
C210_Flyer wrote:
Do you guys have pireps that you report to FSS in real time? Its a really valuable tool for wx briefing and decision making. Too bad the airlines are above doing reports.
To the best of my knowledge there is unfortunately no such thing as PIREPs in Europe. On the other hand you are required to notify ATC of potentially dangerous conditions, but that information is not available for flight planning.
How high is the cloud top here?
I have never seen anything like this…
The sigmet gives a clue.
Gramet for a flight from Helsinki to Moskow shows Cirrus clouds slightly above FL400 …
here is the IR
UUEE Moskau METAR UUEE 012230Z 09009MPS 0900 0800NE R06R/1900N R06L/1900N +SN BLSN VV005 M04/M04 Q1015 R06R/490230 R06L/////// TEMPO 0400 +SHSN BKN010CB=
Topmeteo has a new feature to show cloud tops and bases. They see the tops at FL415.
here it looks quite harmless – don’t think it’s true
@Rwy20 – where do you get that cloud tops chart?
I have seen various colour-coded tops data (e.g. the one posted by nobbi above) but closer inspection showed that they are not taking into account the forecast or actual temperatures aloft and are simply applying the ISA lapse rate, which is obviously useless for GA. We had some threads on this here.
I wonder if this topmeteo one is done correctly.
